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  • Organic Chemistry  (2,690)
  • FLUID MECHANICS AND HEAT TRANSFER
  • AERODYNAMICS
  • 42.75
  • 1995-1999  (3,061)
Collection
Keywords
Publisher
Years
Year
  • 1
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    Notes on Menippus and Issikia from Sumatra and Java, Indonesia (Coleoptera: Chrysomelidae: Galerucinae) (1999)
    In:  Zoologische Mededelingen (00240672) vol.73, 1-11 (1999) p.187
    Details
    Publication Date: 2007-01-23
    Description: Menippus philippinensis Jacoby, 1894, is reported from Java, and Issikia clarki (Jacoby, 1884) comb. nov., from Sumatra.
    Keywords: Coleoptera ; Chrysomelidae ; Galerucinae ; Menippus ; Issikia ; Issikia clarki ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Article / Letter to the editor
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  • 2
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    Nieuwe en oude vindplaatsen van de roofvlieg Machimus cowini in Nederland (Diptera: Asilidae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.9 (1999) p.143
    Details
    Publication Date: 2007-01-10
    Description: New and old records of the robberfly Machimus cowini in the Netherlands (Diptera: Asilidae) Until recently, Machimus cowini (Hobby, 1943) was known from just one record in the Netherlands. An examination of Dutch specimens of the similar M. cingulatus revealed specimens of M. cowini from five new localities. The records are concentrated on the island Ameland and along the rivers Waal and Maas. On Ameland, M. cowini probably occurs in coastal dunes. Near Nijmegen the species was found in grassy vegetation on floodplains and on riverdunes near the river.
    Keywords: Insecta ; Diptera ; Asilidae ; Machimus cowini ; Nederland ; Verspreiding ; Biotopen ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 3
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    The Palaearctic species of the genus Diachasmimorpha Viereck (Hymenoptera: Braconidae: Opiinae) (1999)
    In:  Zoologische Mededelingen (00240672) vol.73, 1-11 (1999) p.1
    Details
    Publication Date: 2007-01-23
    Description: Two new species of the genus Diachasmimorpha Viereck, 1913 (Braconidae: Opiinae) are described: D. feijeni spec. nov. from Bhutan (reared from Bactrocera minax (Enderlein) (Diptera: Tephritidae) in fruits of Citrus reticulata Blanco (mandarin)) and D. budrysi spec. nov. from Far East Russia. A key to the Palaearctic species is added, including two similar species (Fopius alternatae (Tobias, 1977), and F. myolejae (Tobias, 1977)).
    Keywords: Hymenoptera ; Braconidae ; Opiinae ; Diachasmimorpha ; Palaearctic ; Bhutan ; Russia ; key ; Diptera ; Citrus reticulata ; Bactrocera minax ; Tephritidae ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 4
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    Pemphredon montana, een nieuwe graafwesp voor Nederland (Hymenoptera: Specidae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.9 (1999) p.142
    Details
    Publication Date: 2007-01-10
    Description: Pemphredon montana, new to The Netherlands (Hymenoptera: Sphecidae) In 1998 Pemphredon montana Dahlbom, 1845 was recorded for the first time in the Netherlands. The species was found nesting in the insulating material of a caravan in the northernmost part of the province of Overijssel.
    Keywords: Insecta ; Hymenoptera ; Sphecidae ; Crabronidae ; Pemphredon montana ; Nederland ; Verspreiding ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 5
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    Porcellium conspersum, een in Nederland zeer zeldzame landpissebed van vochtige bossen (Crustacea: Isopoda: Oniscoidea) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.9 (1999) p.140
    Details
    Publication Date: 2007-01-10
    Description: The influence of recent inundations on the distribution pattern of the isopod Eluma purpurascens in the province of Zeeland (Crustacea: Isopoda: Oniscoidea) Small scale mapping of Eluma purpurascens Budde-Lund, 1885 in the province of Zeeland revealed a remarkable distribution pattern. The species proved to be absent in parts which have been inundated during and after the second world war. This study shows that for the interpretation of distribution patterns the history of the study area should be considered.
    Keywords: Arthropoda ; Crustacea ; Isopoda ; Oniscoidea ; Nederland ; Verspreiding ; Biotopen ; Herkenning ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 6
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    Faunistiek en ecologie van het zweefvliegengenus Epistrophe in Nederland (Diptera: Syrphidae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.8 (1999) p.33
    Details
    Publication Date: 2007-01-09
    Description: Faunistics and ecology of the syrphid genus Epistrophe in The Netherlands (Diptera: Syrphidae) Ten species of Epistrophe have been found in the Netherlands, two of which, E. cryptica and E. similis, are recorded here for the first time. The distribution, changes in distribution and ecology of the species were investigated and are illustrated by distribution maps and diagrams of the flight period. In all species, except E. eligans, females were observed more than males. Furthermore, females seem to be active later in the season than males. It is discussed that this is probably caused by the differences in behaviour between the males of the species.
    Keywords: Insecta ; Diptera ; Syrphidae ; Epistrophe ; Fenologie ; Verspreiding ; Biologie ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 7
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    De sneeuwspringer Boreus hyemalis in Nederland (Mecoptera: Boreidae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.8 (1999) p.1
    Details
    Publication Date: 2007-01-26
    Description: Until recently Boreus hyemalis was considered to be a rare species in The Netherlands. It was only known from a few localities in The Netherlands in the provinces of Noord-Holland, Zuid- Holland, Utrecht, Gelderland and Drenthe. The last few years many new populations have been discovered. In this paper the first records for the provinces of Limburg, Noord-Brabant and Overijssel are presented. The species seems to prefer scarcely vegetated patches in sanddunes, dominated by greyhair grass Corynephorus canescens and the moss Polytrichum piliferum. It proved to be relatively easy to find, when the right places were searched in the right period (October until February).
    Keywords: Insecta ; Mecoptera ; Boreidae ; Boreus hyemalis ; Sneeuwspringer ; Verspreiding ; Nederland ; Biotopen ; Biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 8
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    The genus Bryotropha in the Netherlands (Lepidoptera: Gelechiidae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.9 (1999) p.79
    Details
    Publication Date: 2007-01-10
    Description: Het genus Bryotropha in Nederland (Lepidoptera: Gelechiidae) Het genus Bryotropha staat bekend als een notoir lastig geslacht van kleine bruine motjes. Die moeilijkheid komt door de variatie, maar vooral ook door gebrek aan bruikbare beschrijvingen. Met dit artikel zijn de negen Nederlandse soorten te determineren. Vanwege het gebrek aan determinatieliteratuur in heel Europa is het in het Engels geschreven. Behalve de maar één keer waargenomen B. domestica, zijn de meeste soorten vrij gewone verschijningen in ons land, zoals uit de kaarten blijkt.
    Keywords: Insecten ; Lepidoptera ; Gelechiidae ; Verspreiding ; Nederland ; Fenologie ; Waardplanten ; Biotopen ; Determinatiesleutel ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 9
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    De valkruidmineervlinder Digitivalva arnicella in Nederland: herontdekking en behoud (Lepidoptera: Plutellidae: Acrolepiinae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.9 (1999) p.15
    Details
    Publication Date: 2007-08-06
    Description: The occurrence of Digitivalva arnicella in the Netherlands: rediscovery and conservation (Lepidoptera: Plutellidae: Acrolepiinae) Digitivalva arnicella (Heyden, 1863), previously only known from two localities before 1902, has been rediscovered in eight localities in the northern part of the Netherlands (province of Drenthe) on its host Arnica montana. On the basis of leafmines, found in old herbarium collections, it can be concluded that the species was once widespread within the range of its host in the northern and eastern parts of the Netherlands and has apparently been overlooked by entomologists since. D. arnicella is a much endangered species in the Netherlands, because of the dramatic decline of its host. Two of the eight discovered populations have been lost since their discovery in the first half of the 1990’s. Systematics and life history of the species are described and illustrated, the distribution is mapped and advise for management of its sites are given. The current management of some populations of Arnica, by mowing the site completely in August, is disastrous for the young caterpillars, mining the leaves.
    Keywords: Acrolepiinae ; Plutellidae ; Yponomeutoidea ; Digitivalva ; Netherlands ; conservation ; Arnica ; Digitivalva arnicella ( Plutellidae- ) ; Habitat management ; Endangered status ; effect of food plant shortage ; conservation proposals ; Food plants ; Arnica montana ; effect on decline to endangered status ; Decline-to-endangered-status ; influences-and-conservation ; Netherlands ; Distribution ; population dynamics and conservation ; endangered species ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 10
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    De boskrekel Nemobius sylvestris in de duinen bij Bergen (Noord-Holland) (Orthoptera) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.8 (1999) p.91-93
    Details
    Publication Date: 2007-01-09
    Description: Nemobius sylvestris in the dunes near Bergen (Orthoptera) A large population of Nemobius sylvestris (Bosc, 1792) has been found in the dunes near Bergen (Noord-Holland), 60 km northwest of the nearest known site in the Gooi-area. This discovery sheds new light on a specimen from Bergen found in a collection, which was thought to be mislabelled.
    Keywords: Insecta ; Orthoptera ; Gryllidae ; Nemobius sylvestris ; Nederland ; Verspreiding ; Biotopen ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 11
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    Interessante libellenwaarnemingen in 1998 (Odonata) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.8 (1999) p.85
    Details
    Publication Date: 2007-01-09
    Description: Interesting new records of Odonata in the Netherlands in 1998 A survey of the most interesting observations on Dutch Odonata is presented. During the Odonata Recording Scheme many new records of rare species have become available. Gomphus flavipes, G. vulgatissimus, Anax parthenope, Sympetrum pedemontanum and S. depressiusculum seem to become more common. The status of some threatened species is elucidated: Calopteryx virgo, Sympecma paedisca, Coenagrion hastulatum and Cordulegaster boltonii.
    Keywords: Insecta ; Odonata ; Verspreiding ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 12
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    The West Palaearctic species of the subfamily Paxylommatinae (Hymenoptera: Ichneumonidae), with special reference to the genus Hybrizon Fallén (1999)
    In:  Zoologische Mededelingen (00240672) vol.73, 1-11 (1999) p.11
    Details
    Publication Date: 2007-01-23
    Description: The West Palaearctic species of the subfamily Paxylommatinae are reviewed and the species of the genus Hybrizon Fallén, 1813, from the Palaearctic region are keyed. Hybrizon juncoi (Ceballos, 1957) is recognized as a valid species, a neotype is designated for Hybrizon latebricola Nees, 1834, and a lectotype is designated for Plancus apicalis Curtis, 1833. Paxylomma grandis Rudow, 1883, Ogkosoma schwarzi Haupt, 1913, and Eurypterna arakawae Matsumura, 1918, are new junior synonyms of Eurypterna cremieri (de Romand, 1838).
    Keywords: Ichneumonidae ; Paxylommatinae ; Hybrizon ; Ghilaromma ; Eurypterna ; keys ; distribution ; Palaearctic ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 13
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    The genus Scrobipalpa in the Netherlands (Lepidoptera: Gelechiidae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.9 (1999) p.29
    Details
    Publication Date: 2007-01-10
    Description: Het genus Scrobipalpa in Nederland (Lepidoptera: Gelechiidae) Scrobipalpa is een geslacht van kleine, lastig uit elkaar te houden motjes. In heel Europa zijn ongeveer 70 soorten bekend. Doorgaans zijn de vleugels bruin- of grijsachtig met een tekening van stippels en strepen die bovendien erg kan variëren. Hierdoor kunnen de individuele soorten vaak moeilijk herkend worden. Aan de hand van de genitaliën kunnen soorten wel allemaal gedetermineerd worden. Omdat de literatuur over deze groep niet erg toegankelijk is en bestaande beschrijvingen soms erg onvolledig zijn, wordt dit artikel in het Engels geschreven. Met dit artikel zijn de elf Nederlandse soorten te determineren. De meeste hiervan zijn min of meer gebonden aan de kust. Van alle soorten worden naast beschrijvingen van de vleugeltekening en de genitaliën, ook de verspreiding, de biologie en de ecologie gegeven.
    Keywords: Insecta ; Lepidoptera ; Scrobipalpa ; Verspreiding ; Biotopen ; Fenologie ; Herkenning ; Determinatiesleutel ; Waardplanten ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 14
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    Cheilosia caerulescens in Nederland in 1998 (Diptera: Syprhidae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.8 (1999) p.93
    Details
    Publication Date: 2007-01-09
    Description: New records of Cheilosia caerulescens in the Netherlands (Diptera: Syrphidae) Cheilosia caerulescens is a rare hoverfly in The Netherlands. Until 1998 only four records were known, the first in 1986. In 1998 the species was found on three new and one old locality. The record from Heemstede (province of Noord-Holland) is among the northernmost in the European distribution of this species. Three of the four records originate from gardens.
    Keywords: Insecta ; Diptera ; Syrphidae ; Cheilosia caerulescens ; Nederland ; Verspreiding ; Biotopen ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 15
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    Dansmuggen in natuurontwikkelingsgebieden (Chironomidae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.8 (1999) p.89
    Details
    Publication Date: 2007-01-09
    Description: Chironomidae in newly created nature reserves In a newly created nature reserve near Eindhoven many interesting species of Chironomidae were found. Several new species to the Dutch fauna were identified and one species (of the genus Neozavrelia) proved to be new to science. The fauna of these young habitats is poorly known, but proves to be very interesting.
    Keywords: Insecta ; Chironomidae ; Verspreiding ; Biotopen ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 16
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    Four new species of Pteromalus Swederus (Hymenoptera: Chalcidoidea: Pteromalidae) and redescriptions of three other species (1999)
    In:  Zoologische Mededelingen (00240672) vol.73, 1-11 (1999) p.165
    Details
    Publication Date: 2007-01-23
    Description: A key to the European species of the Pteromalus altus group is presented. The relationship between this group and species of the genus Euphorbia (Euphorbiaceae) is confirmed. One new species: P. villosae, associated with Euphorbia villosa Waldst. & Kit.is presented. Two new species of the albipennis group: Pteromalus almeriensis and P. costulata are presented. In addition one species of the P. vibulenus group: P. tethys is added. Information on P. sylveni Hedqvist, P. osmiae Hedqvist and P. discors Graham is given.
    Keywords: Chalcidoidea ; Pteromalidae ; Pteromalus ; new species ; redescriptions ; Spain ; Portugal ; France ; Greece ; Euphorbia ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 17
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    The Egyptian species of Encarsia (Hymenoptera: Aphelinidae): a preliminary review (1999)
    In:  Zoologische Mededelingen (00240672) vol.73, 1-10 (1999) p.131
    Details
    Publication Date: 2007-01-23
    Description: The species of Encarsia Foerster (Hymenoptera: Aphelinidae) known from Egypt are revised. A total of 14 species are treated, including one new species. E. indifferentis Mercet, 1929, is synonymised with E. inaron (Walker, 1839). All species are fully described or diagnosed, and illustrated. Host records, and species-distributions outside Egypt, are given.
    Keywords: Egypt ; Encarsia ; Aleyrodidae ; Aphelinidae ; Diaspididae ; parasitoids ; biological control ; natural enemies ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 18
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    Bijzondere kevervondsten in Nederland (Coleoptera: Staphylinidae, Nitidulidae, Dermestidae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.9 (1999) p.133
    Details
    Publication Date: 2007-01-10
    Description: Interesting records of beetles in The Netherlands (Coleoptera: Staphylinidae, Nitidulidae, Dermestidae) Tachyporus quadriscopulatus Pandellé, 1869 has been recorded for the second time in the Netherlands at Arcen and Velden, province of Limburg. After 27 years, a third record of Carpophilus marginellus Motschulsky, 1858 can be reported from St. Geertruid, in the southern part of the province of Limburg. One specimen was found outdoors, in a wood. One specimen of Anthrenocerus australis Hope, 1843 was also found outdoors, in Oost- Maarland also in southern Limburg, sitting on a flower in a meadow.
    Keywords: Insecta ; Coleoptera ; Staphylinidae ; Nitidulidae ; Dermestidae ; Nederland ; Verspreiding ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 19
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    Dagvlinders in 1998: nog steeds onder druk (Lepidoptera: Rhopalocera) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.9 (1999) p.127
    Details
    Publication Date: 2007-01-10
    Description: Butterflies in the Netherlands still under pressure (Lepidoptera: Rhopalocera) New information on the Dutch Rhopalocera fauna since the distribution atlas of Tax (1989) is presented. Coenonympha pamphilus was common in large parts of the Netherlands, but has declined dramatically. C. arcania is now formally extinct in our country. An extensive research showed that Maculinea alcon ericae has dissappeared from many sites. Furthermore the smallest of the two remaining populations of Heteropterus morpheus seems to have gone extinct. On the other hand, Callophrys rubi, has colonized new territory. Lampidus boeticus, was observed once as an adult and once a caterpillar was found between snow peas from Egypt. Colias croceus was very abundant in 1998. The reintroductions of Maculinea teleius and M. nausithous in 1990 appear to have been successful.
    Keywords: Insecta ; Lepidoptera ; Rhopalocera ; Verspreiding ; Bedreiging ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 20
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    De edelherthorzel Cephenemyia auribarbis gekweekt (Diptera: Oestridae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.9 (1999) p.109
    Details
    Publication Date: 2007-01-10
    Description: The rearing of the botfly Cephenemyia auribarbis (Diptera: Oestridae) After several failures we finally succeeded in rearing botflies Cephenemyia from third-instar larvae. From a red deer shot at 13 March 1998 about one hundred larvae of Cephenemyia auribarbis (Meigen, 1824) were collected. Ten individuals reached the pupal stage. After 22 days, one fullgrown male died in the pupa, and two males emerged and lived for 17 and 18 days respectively. This is one of the few recorded succesful attempts to rear botflies.
    Keywords: Insecta ; Diptera ; Oestridae ; Cephenemyia auribarbis ; Nederland ; Verspreiding ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 21
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    Een nieuwe vondst van het locomotiefje Chorthippus apricarius in Nederland (Orthoptera) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.8 (1999) p.90
    Details
    Publication Date: 2007-01-09
    Description: A new record of Chorthippus apricarius in the Netherlands (Orthoptera) Chorthippus apricarius is a very rare grasshopper in The Netherlands. Only three, very widely separated sites are known. In 1998 a small new population has been found in a roadside verge, 2 km southwest of the southernmost site in the south of the province of Limburg.
    Keywords: Insecta ; Orthoptera ; Acrididae ; Chorthippus apricarius ; Locomotiefje ; Verspreiding ; Biotopen ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 22
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    Naamlijst van de glanskevers van Nederland en het omliggende gebied (Coleoptera: Nitidulidae & Brachypteridae) (1999)
    In:  Nederlandse Faunistische Mededelingen (01692453) vol.8 (1999) p.11
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    Publication Date: 2007-01-09
    Description: Checklist of the Nitidulidae and Brachypteridae (Coleoptera) of the Netherlands and surrounding regions An annotated checklist of the Nitidulidae and Brachypteridae of the Netherlands and surrounding regions is presented, based mainly on literature research. Since the list of Brakman seven new species to the Netherlands have been published. One of these species, Pocadius adustus, is listed here for the first time. Major nomenclatorial changes, published elsewhere, have been implemented. The list contributes to the faunistic work of the European Invertebrate Survey - The Netherlands. A separate list of hostplants of the Nitidulidae and Brachypteridae is presented.
    Keywords: Insecta ; Coleoptera ; Nitidulidae ; Brachypteridae ; Glanskevers ; Verspreiding ; Waardplanten ; Biologie ; Naamlijst ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 23
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    Galeruca malakkana spec. nov. from Malaysia (Coleoptera: Chrysomelidae: Galerucinae) (1998)
    In:  Zoologische Mededelingen (00240672) vol.72, 1-10 (1998) p.101
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    Publication Date: 2007-01-26
    Description: Galeruca malakkana spec. nov., a new species is described from Malaysia.
    Keywords: Coleoptera ; Chrysomelidae ; Galerucinae ; Galeruca ; new species ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 24
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    Bobekoides gen. nov. (Hymenoptera: Braconidae: Alysiinae) from South Africa (1998)
    In:  Zoologische Mededelingen (00240672) vol.72, 1-10 (1998) p.105
    Details
    Publication Date: 2007-01-23
    Description: A new genus of the subfamily Alysiinae (Braconidae) is reported from South Africa (Bobekoides gen. nov.; type species: Bobekoides fulvus spec. nov.), illustrated, and described. A key to the species is added. The new genus is closely related to the East Palaearctic genus Hylcalosia Fischer, 1967.
    Keywords: Hymenoptera ; Braconidae ; Alysiinae ; Alysiini ; Bobekoides ; Afrotropical ; South Africa ; key ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Article / Letter to the editor
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  • 25
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    Synopsis of the Neotropical genus Rhodopygia Kirby, 1889 (Odonata: Libellulidae) (1998)
    In:  Zoologische Mededelingen (00240672) vol.72, 1-10 (1998) p.1
    Details
    Publication Date: 2007-01-23
    Description: A synopsis of the genus Rhodopygia Kirby is given. Its species are discussed and their diagnostic morphological characters elucidated by figures. The hitherto unknown females of R. hinei Calvert and R. pruinosa Buchholz are described. A key to the species is provided.
    Keywords: Libellulidae ; Rhodopygia ; Central and South America ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Article / Letter to the editor
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  • 26
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    Phaenocarpa helophilae spec. nov. (Hymenoptera: Braconidae), a gregarious parasitoid of Helophilus larvae (Diptera: Syrphidae), with notes on related species (1998)
    In:  Zoologische Mededelingen (00240672) vol.72, 1-10 (1998) p.15
    Details
    Publication Date: 2007-01-23
    Description: For the first time a gregarious parasitoid belonging to the genus Phaenocarpa Foerster, 1862 (Braconidae: Alysiinae) is reported, and described as P. helophilae spec. nov. from England. The first record of Chloropidae as host for a Phaenocarpa species is given; P. livida (Haliday, 1838) reared from Calamoncosis (Rhaphiopyga) glyceriae Nartshuk, 1958. Sathra debilis Foerster, 1862, is synonymised with P. livida (Haliday). Additionally, Phaenocarpa curticauda spec. nov. from The Netherlands is described and fully illustrated. A lectotype is designated for Alysia pectoralis Zetterstedt, 1838, and Phaenocarpa rufoflava Papp, 1968, is recognised as a valid species.
    Keywords: Hymenoptera ; Braconidae ; Alysiinae ; Alysiini ; Phaenocarpa ; Diptera ; Syrphidae ; Chloropidae ; Helophilus ; Calamoncosis ; Europe ; Palaearctic ; distribution ; biology ; gregarious ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Article / Letter to the editor
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  • 27
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    Cladistics and biogeography of the assassin bug genus Rasahus Amyot & Serville (Heteroptera: Reduviidae: Peiratinae) (1998)
    In:  Zoologische Mededelingen (00240672) vol.72, 1-10 (1998) p.73
    Details
    Publication Date: 2007-01-23
    Description: The assassin bug genus Rasahus Amyot & Serville (Heteroptera: Reduviidae: Peiratinae) comprises 26 Neotropical species. A cladistic analysis of the genus was carried out using 63 characters from external morphology, body vestiture, and male and female genitalia, with the species considered as terminal taxa. The analysis yielded 149 equally parsimonious cladograms, each with 206 steps, CI = 0.35, and RI = 0.60; the successive weighting procedure resulted in eight cladograms (CI = 0.79 and RI = 0.91). In the strict consensus cladogram, two major clades are delimited: one comprising the species R. rufiventris, R. hamatus, R. arcitenens, R. arcuiger, R. amapaensis, R. thoracicus, R. biguttatus, R. argentinensis, R. limai, R. grandis, and R. angulatus; and the other with R. castaneus, R. aeneus, R. scutellaris, R. maculipennis, R. brasiliensis, R. sulcicollis, R. surinamensis, R. albomaculatus, R. guttatipennis, R. atratus, R. peruensis, R. costarricensis, R. bifurcatus, R. flavovittatus, and R. paraguayensis. A cladistic biogeographic analysis of the provinces of the Neotropical subregion, considering distributional data of the species of Rasahus and three other genera of Peiratinae (Eidmannia, Melanolestes, and Thymbreus) was carried out. Four general area cladograms were obtained applying programs COMPONENT 2.0 and TASS. The most parsimonious general area cladogram (= implying fewer items of error) was obtained with COMPONENT 2.0 minimizing the number of leaves added, and shows the sequence (Desierto, (Caatinga, (Cerrado, (Chacoan, (Caribbean, Amazonian), (Paranaense, Atlantic))))). This sequence of area relationships is congruent with the history previously hypothesized for the subregion, where the development of an open vegetated diagonal (comprising the Chacoan, Cerrado, and Caatinga provinces) due to the aridification induced by the gradual uplift of the Andes, separated the former Amazonian forest in a northwestern part (Caribbean plus Amazonian provinces) and a southeastern part (Paranaense plus Atlantic provinces).
    Keywords: Cladistics ; biogeography ; Rasahus ; Heteroptera ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Article / Letter to the editor
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  • 28
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    Revisionary notes on Bentonia van Achterberg, 1992 (Hymenoptera: Braconidae: Orgilinae) with description of two new species (1998)
    In:  Zoologische Mededelingen (00240672) vol.72, 1-10 (1998) p.51
    Details
    Publication Date: 2007-01-26
    Description: Two new species of the genus Bentonia van Achterberg, 1992 (Braconidae: Orgilinae) (B. inca from Peru and B. xochiquetzalis from Mexico) are described and partly illustrated. A third undescribed species was found for which some characters are listed. The distribution of B. scutellaris van Achterberg, 1992, is extended west to Peru and B. longicornis van Achterberg, 1992, north to Venezuela. An identification key is added.
    Keywords: Braconidae ; Orgilinae ; Bentonia ; Peru ; Mexico ; Venezuela ; key ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 29
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    Glycopeptide Synthesis Using O-Pentafluorophenyluronium Salts as novel condensing reagents (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 233-239 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pentafluorophenyluronium salts and related coupling reagents for the solid-phase synthesis of peptides and glycopeptides have been developed and employed in the synthesis of a glycopeptide sequence from the cell adhesion molecule E-CAD 1.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400306
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  • 30
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    A. Bianchi, K. Bowman-James, E. Garcia-Espana (Hrsg.), Supramolecular chemistry of anions, 1. Aufl., 461 S., 175 Abb., 37 Tab., New York, Chichester, Weinheim, Brisbane, Singapore, Toronto, WILEY-VCH, 1997, DM 118,-, £ 65,-, ISBN 0-471-18622-8 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 486-487 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400515
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  • 31
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    Volker Koß, Umweltchemie, Eine Einführung für Studium und Praxis, 1. Auflage, 1997, 110 Abb., 74 Tab., 288 Seiten, gebunden DM 58,-, ÖS 423,40, sFr 53,-, GBP 22,50, US $ 36,25, Berlin-Heidelberg-New York-London-Paris-Tokyo-Hong Kong, Springer-Verlag, ISBN 3-540-61830-9 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 488-490 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400519
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  • 32
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    Hochreaktive Trialkylsilylierungsreagentien aus Bis(trifluormethansulfonyl)imid - Silylierung von funktionellen Gruppen, alkinen und reaktiven AromatenDie neuartigen Trialkylsilylierungsreagenzien O-(Triisopropylsilyl)-bis-(trifluormethansulfonyl)imid; O-(tert Butyldimethylsilyl)-bis-(trifluormethansulfonyl)-imid und N-(Trimethylsilyl)-bis-(trifluormethansulfonyl)-imid werden demnächst bei Fluka kommerziell erhältlich sein. (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 506-512 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Highly Reactive Trialkylsilylation Reagents Derived from Bis(trifluoromethanesulfonyl)imide - Silylation of Functional Groups, Alkines and Reactive AromaticsThe synthesis of trialylsilyl-bis(trifluormethane-sulfonyl)imides 3 is described. Compounds 3 with bulky trialkylsilyl groups 3a,b only exist in the silatautomeric form 3a′, b′ under usual conditions, 3c in the N-trimethylsilyl structure. Despite of the bulky silyl substituents in 3a′, b′ their reactivity is higher than of trimethylsilyltriflate. Alcohols, carbonyl compounds, nitroalkanes and carboxylic acid esters are silylated in good yields, especially by the more reactive triisopropylsilyl derivative 3b′ in presence of tertiary amines. tert.-Butyl carboxylates and benzylcarboxylates are cleaved. Monosubstituted alkines and electron-rich (hetero) aromatics are carbosilylated in presence of N-ethyl-diisopropylamine.
    Additional Material: 4 Tab.
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    URL: http://dx.doi.org/10.1002/prac.19983400603
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  • 33
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    Amphiphile und Mesogene Kohlenhydrate. 10. Mesophasenwechsel bie amphiphilen Tetradecyl-(N-acylamino)-2-desoxy-1-thio-β-D-glucopyranosiden durch Acylkettenvariation (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 544-550 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Amphiphilic and Mesogenic Carbohydrates. 10. Change of the Type of the Mesophase by Variation of the Acyl Chain of Amphiphilic Tetradecyl (N-acylamino)-2-deoxy-1-thio-β-D-glucopyranosidesThe homologous amphiphilic tetradecyl-2-(N-alkanoylamino)-2-deoxy-1-thio-β-D-glucopyranosides 5a-f were synthesized from the 2-(N-alkanoylamino)-2-deoxy-D-glucopyranoses 1a-f via the glucosyl chlorides 2a-f, the glucosyl isothiuronium chlorides 3a-f, and the acetylated thioglucosides 4a-f. On heating the amphiphiles 5a-f form different types of liquid crystalline phases in dependence of the length of the acyl chain, i.e. 5a and 5b form smectic phases, 5d-f form columnar mesophases. Polarisation microscopy, DSC-measurements and contact preparations were used to characterise the liquid crystaline phases.
    Additional Material: 3 Ill.
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    URL: http://dx.doi.org/10.1002/prac.19983400607
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  • 34
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    Synthesis of Optically Active 4-Hydroxypyrazolidin-3-ones as precursors for β-amino-α-hydroxycarboxylic acid derivativesDedicated to Professor Dr. Hans-Georg Henning on the Occasion of his 70th Birthday (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 567-571 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cis or trans-glycidic esters 1 or 7 give ring transformations with hydrazines affording optically active 4-hydroxypyrazolidin-3-ones 3 and 4 or 6 or 9 and 10, respectively, in different regioselectivities. 4-Hydroxypyrazolidin-3-ones 3 and 9 can serve as precursors for enantiomerically pure β-amino-α-hydroxycarboxylic acid amides 5 and 11 by hydrogenation in the presence of Raney-Ni.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/prac.19983400611
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  • 35
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    Pd2(dba)3 · CHCl3/AsPh3 - a powerful catalyst system for Pd(0)-mediated C—C-bond formation (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 90-93 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400114
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  • 36
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    Masthead (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998) 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400101
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  • 37
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    3,1′-Bridged 2-[2′-(4″-dialkylaminophenyl)ethenyl] pyrylium and 1-Benzopyrylium Dyes - Synthesis and Vis/NIR Absorption/Emission BehaviourDedicated to Prof. Dr. A. R. Katritzky on the Occasion of his 70th Birthday (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 214-222 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new 3,1′-bridged 2-[2′-(4″-dialkylaminophenyl)ethenyl]-4,6-diarylpyrylium perchlorates (3), 2-[2′-(4″-dialkylaminophenyl)ethenyl]-7-diethylamino-1-benzopyrylium perchlorates 5-8, 2-[4′-(4″-dialkylaminophenyl)butadien-1′,3″-yl]-, and 2-[2′-(7″-diethylaminocoumar-3″-yl)ethenyl]-7-diethylamino-1-benzopyrylium perchlorates 10-12 were synthesized and characterized by means of elemental analysis, m.p., Vis/NIR, and 1H NMR spectra. Semiempirical MO calculations were performed to elucidate the essential features of the chromophores. The size of the bridging ring strongly affects the geometry of the chromophores which, in turn, determines the extent of charge transfer of the longest wavelength electronic transition. Increasing deviation from planarity causes the polymethine-like chromophore to become more polyene-like.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/prac.19983400304
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  • 38
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    Non-steroidal anti-inflammatory agents. Part 23. Synthesis and Pharmacological Activity of Enaminones which inhibit both bovine cyclooxygenase and 5-lipoxygenase (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 256-263 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis and stereochemical characteristics of pyrrolidino-, isoquinolino- and indolo-enaminones 2-11 are reported. The inhibition of cyclooxygenase was determined in a bovine thrombocyte intact cell assay and that of 5-lipoxygenase using intact bovine polymorphonuclear leucocytes. Except compound 2c′ which is a well-balanced dual inhibitor of both enzymes, all other enaminone derivatives are weak inhibitors of both cyclooxygenase and 5-lipoxygenase. Structure-activity relationships of the enaminones in relation to known anti-inflammatory drugs are discussed.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/prac.19983400309
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  • 39
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    Masthead (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998) 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400401
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  • 40
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    Alkoxycarbonylcarbene Transfer to Acyclic Tertiary EnaminonesPresented in part at the third conference on iminium salts, Stimpfach-Rechenberg (Germany), September 17-19, 1997 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 315-322 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copper-catalyzed alkoxycarbonylcarbene transfer from methyl or tert-butyl diazoacetate to acyclic enaminoesters 6a,b and enaminocarboxanilide 13 yields vicinal push-pullsubstituted cyclopropanes 7a,b,8, and 14. In contact with dry silica gel, the latter compounds undergo facile ring-opening leading to enaminoesters 9, 10, and 15. Treatment with aqueous acid transforms 9 and 10 into 2-acylsuccinates 11 and 12, and 15 into pyrrolinone 16. Methoxycarbonylcarbene transfer to enaminoketones 1a-c does not yield isolable cyclopropanes, but after hydrolytic work-up α-acyl-γ-ketoesters 2a-c are obtained.
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    URL: http://dx.doi.org/10.1002/prac.19983400405
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  • 41
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    Iminiumsalze in quantitativen Gas/Festköper- und Festkörper/Festkörper-ReaktionenTeil eines Vortrags zur 3. Fachtagung büer Iminiumsalze, Stimpfach-Rechenberg, 17.-19. September 1997 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 346-355 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Iminium Salts in Quantitative Gas/Solid and Solid/Solid ReactionsIminium salts that are highly susceptible to hydrolysis are quantitatively prepared and reacted in the solid state without solvents or liquid phases. Atomic force microscopy AFM helps in elucidating the mechanism of these still unusual gas-solid and solid-solid syntheses by recording surface topographies of reacting crystals of L-histidine (10) and triphenylverdazyl (15). Various imines add gaseous HCl or HBr to form stable iminium halides (1, 3, 4, 5, 11) even if frozen liquids of very weak heterocyclic bases are treated at low temperatures. Another way for quantitative yields of iminium salt hydrates (6) starts with solid primary ammonium halides and gaseous acetone. o-Phenylenediamines (7) give quantitatively 1,5-benzodiazepines (9) by solid state cyclization of bis-iminium salt intermediates (8). Crystalline nitroxyls (12) and triphenylverdazyl (15) undergo stoichiometric one-electron transfer with gaseous NO2 or XeF2 to give nitrosonium (14) and azonium salts (17). The solid state chlorination of tetramethylthiuramdisulfide (18) or dimethylthiocarbamoylchloride (20) yields phosgene dimethyliminiumchloride (Viehe salt 21) in quantitative yield. Solid Viehe salt is quantitatively treated with gaseous Cl2 to give the trichloride 19 and solid SbCl5 or PCl5 to produce the hexachloroantimoniates (22), -phosphates (23). Solid brenzcatechol (24), mercaptobenzimidazole (27), p-nitroaniline (30), N-methylbenzothiazolone-2-hydrazone (34) and acetophenone (41) are treated with 21 to give the corresponding chloroiminium salts (25, 28, 31, 35, 43). p-Toluenesulfonamide (37) and 22 give the chloroiminium salt 38. These quantitative solid-solid reactions are most easily run in ball mills with cooling device. The “waste-free” techniques achieve exclusion of moisture in an elegant way. The preparative use of the versatile products with nucleophiles is indicated. The three-step solid-state mechanisms are discussed.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/prac.19983400409
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    Preparation and properties of 2-Dialkylamino-5-haloacetyl-thiazoles and 4-(2-Dialkylamino-5-thiazolyl)-thiazolesPresented in part at the third conference on iminium salts, Stimpfach-Rechenberg (Germany), September 17-19, 1997 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 375-380 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: By the reaction of N-acylthioureas 7 with 1,3-dichloroacetone 9 2-dialkylamino-5-chloroacetyl-thiazoles 11 are available. These compounds react with thioureas or arylthioamides under heterocyclisation to give bis-(2-dialkylamino-5-thiazolyl)-ketones 13, 2-aryl-4-(2-dialkylamino-5-thiazolyl)-thiazoles 14, or 2-dialkylamino-4-(2-dialkylamino-5-thiazolyl)-thiazoles 15, resp., from which the last-mentioned compound exhibit a high reactivity towards several electrophilic reagents. Thus, deeply colored cyanovinyl, arylazo, and arylmethine substituted bisthiazole dyes 17, 18, and 19, resp., have been formed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400413
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    Heterobimetallische Komplexe mit 2-(Dimethylaminomethyl)ferrocenyl-LigandenHerrn Professor Heinrich Nöth zum 70. Geburtstag gewidmet (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 393-407 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Heterobimetallic Complexes Containing 2-(Dimethylaminomethyl)ferrocenyl LigandsThe chemistry of heterobimetallic complexes containing the 2-(dimethylaminomethyl)ferrocenyl ligand is reviewed, including main group element, transition metal, and f-element derivatives. An overview on synthetic methods and molecular structures is given.
    Additional Material: 23 Ill.
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    URL: http://dx.doi.org/10.1002/prac.19983400502
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    LINK Synthesis with 3-Hydroxy-1H-pyrazoles: 3-Carboxyisoalkyloxy-1H-pyrazoles - bicyclic acylpyrazolium salts and γ-Lactams - 3-Carboxyisoalkyloxy-4,5-dihydro-1H-pyrazol-5-onesDedicated to Prof. Dr. Dr. h. c. mult. A. R. Katritzky, FRS, on the Occasion of his 70th Birthday (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 437-449 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1-Substituted 3-hydroxy-1H-pyrazoles 1 react with chloroform, NaOH, and aceton resp. butan-2-one O-regiospecifically to yield 2-methyl-2-[(1H-pyrazol-3-yl)oxy]-propanoic resp. -butanoic acids 14 via a dichlorocarbene (12)-dichlorooxirane (9) pathway. Chlorides 17 of 14 easily cyclize to N-acylpyrazolium salts 18/19, which quantitatively afford esters 22-26 and amides 27-29 of 14. Enantiomers of the butanoic acid 14th, obtained via their diastereomeric cholesterol esters, differ in their stimulus to peroxisome proliferation. At 140 °C pyrazolium salts 18 undergo thermolysis to bicyclic β-oxa-γ-lactams 30-32. 3-Carboxyisoalkylamino-pyrazoles similarly give 1H-β-aza-γ-lactams 34. Reactions of 14 with surplus SOCl2 result in 6-chloro- 37 resp. 7-chloro-β-oxa-γ-lactams 38 via chlorosulfinylation and extrusion of SO, and in 4,4-bispyrazolyl-sulfoxide 39. A mild introduction of additional O-functions into pyrazoles affording 4,5-dihydro-3-hydroxy-5-oxo-1H-pyrazoles 52-57 is presented. Biological effects of the new pyrazoles are protection against shock and ADP-induced thromboembolism, reduction of serum lipids and improvement of blood flow.
    Additional Material: 4 Tab.
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    URL: http://dx.doi.org/10.1002/prac.19983400506
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    The Use of 2-Vinylanilines in the Synthesis of Indole- and Quinoline-DerivativesPresented in part at the third conference on iminium salts, Stimpfach-Rechenberg (Germany), September 17-19, 1997 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 309-314 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cyclization reactions of 2-vinylaniline derivatives, proceeding via anils, amides, imidic acid esters, ureas, thioureas, carbodiimides, formamidine ylids, sulfonamides or ketenes, leading to quinoline or indole derivatives, are described. In a short introduction interesting results from the literature, excluding our results, are presented. In the centre of this progress report our results on acid catalyzed reactions of 2-vinylanilines with aldehydes and ketones are discussed in a more detailed manner.
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    URL: http://dx.doi.org/10.1002/prac.19983400404
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    Convenient preparation of aromatic aldehydes via DDQ oxidation. Application in the Synthesis of a Tripodand Containing Octahydroacridine MoietiesPresented in part at the third conference on iminium salts, Stimpfach-Rechenberg (Germany), September 17-19, 1997 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 341-345 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 7-Methyloctahydroacridines 7a-d were obtained by a one-pot imine condensation/Lewis acid-catalyzed cyclization from aniline derivatives 5a-d and aldehyde 6. Only those compounds 7 could be oxidized with DDQ to the corresponding octahydroacridine-7-carbaldehydes 9, which bear a meta-chloro or bromo substituent (with respect to the methyl group) in addition to the para-amino group (i.e. 7c,d → 9c,d). Aldehyde 9c was further converted to the novel tripodand 11 which was characterized by X-ray crystal structure analysis.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/prac.19983400408
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    From donor and acceptor substituted meta- and para-xylenes to para-Quinodimethanes and Poly(meta-phenylenevinylene)sPresented in part at the third conference on iminium salts, Stimpfach-Rechenberg (Germany), September 17-19, 1997 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 367-374 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ortho-, meta- and para-xylenes 1, 13a, 13b and 13c, with donor and acceptor substituents at the α- and α′ positions, lead to a remarkable variety of intermediates and reaction products after deprotonation of the benzylic proton. Thus, the reaction of para-(cyanomethyl)dialkyl[(methylthio)phenylmethylene]ammonium tetrafluoroborates 13a and 13b with sodium hydride affords the para-quinodimethanes 14a and 14b. Poly(meta-phenylenevinylene) 14c can be obtained when starting from 13c. We report the synthesis of para-quinodimethanes 14a and 14b and poly(meta-phenylenevinylene) 14c and describe a successive approach towards meta-phenylenevinylenes of definite length 16b and 17b starting from 12d. Moreover, we compare the stability and reactivity of para-quinodimethane 14a and 14b with those of the ortho-quinodimethane 2 and we focus on the characterization of the resulting donor and acceptor substituted compounds.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/prac.19983400412
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    Masthead (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998) 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400501
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    Electroreduction of organic compounds. 31. Electroreduction of 2- and 3-Chlorodibenzofuran in Deuterated Methanol (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 430-436 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cathodic reduction of dibenzofuran (2), 2-chlorodibenzofuran (4), and 3-chlorodibenzofuran (1) in deuterated methanol is investigated. The Birch-type reduction product 1,4-dibenzofuran (3) is formed from 1 via 2, whereas 2-chloro-1,4-dihydrodibenzofuran (5) is obtained as by-product besides 3 from 4 as starting compound. Deuterium is only incorporated into the reduction products if CH3OD or CD3OD but not if CD3OH are used. This observation is strongly indicative of a polar mechanism involving protonation rather than a radical mechanism with hydrogen atom abstraction to be operative.
    Additional Material: 4 Ill.
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    Hydroformylierung von Buta-1,3-dien und butadienhaltigen Kohlenwasserstoffraktionen nach dem ZweiphasenverfahrenHerrn Professor em. Dipl.-Ing. Dr. techn. habil. Dr. h. c. Friedrich Asinger in Verehrung gewidmet (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 459-467 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two-phase Hydroformylation of Buta-1,3-diene and Hydrocarbon Mixtures Containing Buta-1,3-dieneThe two-phase hydroformylation of buta-1,3-diene with (HRh(CO)[P(m-C6H4SO3Na)3]3 the Kuntz catalyst system with excess P(m-C6H4SO3Na)3) gives high yields of C5-monoaldehydes. Main product in this mixture is the reactive trans- and cis-pent-3-enal. In consecutive reactions the pent-3-enal is partially hydrogenated to n-pentanal, but also-favoured by the protolytic milieu of the two-phase reaction- aldol condensated to 2-propenylheptadienal. The hydrogenation product of the propenylheptadienal, 2-propylheptanol-1, is a good plasticizer alcohol with a wanted low vapour pressure. Especially promising is the two-phase hydroformylation of the unrefined C4-fraction of the naphtha pyrolysis: after a more than 95 per cent conversion of the buta-1,3-diene also more than 80 per cent of the n-but-1-ene in the C4-fraction is hydroformylated mainly to wanted n-pentanal. Less than 5-10% of the n-but-2-enes and the isobutene in the C4-fraction react under these conditions to oxo-products (2- and 3-methylbutanal). Acetylenic compounds in the C4-fraction are converted quantitatively into products.
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    URL: http://dx.doi.org/10.1002/prac.19983400509
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    Dirhodium(II) tetrakis(methyl pyrrolidone-5-carboxylate) [Rh2(5R-mepy)4 and Rh2(5S-mepy)4] and related chiral rhodium catalysts (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 479-482 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
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    URL: http://dx.doi.org/10.1002/prac.19983400513
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    A. F. Pozharskii, A. T. Soldatenkov und A. R. Katritzky, Heterocycles in life and society, 1st. ed., 301 p., Chichester-New York-Weinheim-Brisbane-Singapore-Toronto, John Wiley & Sons, 1997, £ 19.99, ISBN 0471960349 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 487-488 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400517
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    Masthead (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998) 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400601
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    Transition metal complexes in organic synthesis. Part 46. Synthesis of 5-arylmethyl-substituted tricarbonyl(1-4-η-cyclohexa-1,3-diene)iron complexes (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 530-535 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of tricarbonyl(η5-cyclohexadienylium) iron tetrafluoroborate 3 with the methyl arylacetate 6, the dimethyl arylmalonate 12, and the di-tert-butyl arylmalonate 14 provides regio- and stereoselectively the tricarbonyliron-complexed 5-arylmethylcyclohexa-1,3-dienes 7, 13 and 15.
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    Generation and investigation of various (alkylamino)phenylsilyllithium species - behaviour in coupling reactions with chlorosilanesDedicated to Professor G. Marx on the Occasion of his 60th Birthday (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 557-561 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The partially diethylamino substituted phenyl-chloromono- and -disilanes Cl2Ph(NEt2)Si(2) Cl2Ph(NEt2)2Si(3), [ClPh(NEt2)Si-]2 (7) and Cl(NEt2)PhSi—SiPh(NEt2)2 (8) were synthesized. 3 and 8 are able to react with lithium powder to form the corresponding silyllithium compounds. The resulting species were characterized in solution by 13C and 29Si NMR spectroscopy. To prove the expected substitution patterns of the silyllithium compounds some coupling reactions with chlorosilanes were carried out and the resulting new oligosilanes were characterized by means of NMR spectroscopy and MS.
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    Application of phase transfer catalysis (PTC) without solvent in organic synthesis. IV. Selective O-Alkylation of Hydroxy-phenothazine and Hydroxy-diphenylamine Derivatives (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 576-577 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The exclusive O-alkylation reaction of hydroxy-phenothiazine 3 and hydroxy-diphenylamine derivates 1 and 2 by PTC without solvent is described.
    Additional Material: 1 Tab.
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    P. Nuhn, Naturstoffchemie - Mikrobielle, pflanzliche und tierische Naturstoffe, 3. Aufl., 766 S., 441 Abb., 85 Tab., S. Hirzel Verlag Stuttgart-Leipzig, 1997, DM 220,-, ISBN 3-7776-0613-8 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 585-585 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400617
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    Ring Transformations of 4,5- to the Isomeric 3,4-Disubstituted Isothiazolium Salts and their oxidation to 1,1-dioxidesPresented in part at the third conference on iminium salts, Stimpfach-Rechenberg (Germany), September 17-19, 1997Herrn Prof. Dr. Horst Hartmann zum 60. Geburtstag gewidmet (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 361-366 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 4,5-Disubstituted N-phenyl-isothiazolium salts 1 with active 5-methyl group react under the influence of anilines to form 3,4-disubstituted isothiazolium salts 3. The influence of donor and acceptor substituents in the 2-phenyl group of 1a-h and in the anilines 2 on the ring transformation were studied. The structure of the new salts was confirmed by X-ray analysis. The 3-hydroperoxy-2,3-dihydro-isothiazole 1,1-dioxides (12a,d) and the isothiazole-3(2H)-one 1,1-dioxides (14a,d) are obtained by oxidation of salts 3 with H2O2.
    Additional Material: 2 Ill.
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    Bimolecular formation of radicals by hydrogen transfer. 14. The uncatalyzed Transfer Hydrogenation of α-Methylstyrene by 2,6-disubstituted 9,10-Dihydroanthracenes (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 642-648 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2,6-Dimethoxy-(4a), 2,6-bis(dimethylamino)-(4b), 2,6-dichloro- (4c) and 2,6-dimethoxycarbonyl-9,10-dihydroanthracene (4d) were prepared by conventional methods and used as hydrogen transfer donors to α-methylstyrene (5) between 290-350 °C. The mechanism followed second order kinetics and the rate constants were only slightly influenced by the solvent polarity and the type of substituents introduced. The activation parameters are also closely similar in the series with ΔS≠ values between -21 and -28 cal/mol K. These results, together with the observation of a large isotope effect (kH/kD = 1.4-2.0 at 310-350 °C), suggest that the mechanism involves a primary kinetic H-atom-transfer from the donors to α-methylstyrene (5) in the rate determining step. The compounds 4a-4d constitute a new probe for investigating polar effects on H-transfer reactions.
    Additional Material: 2 Ill.
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    Untersuchungen zur stereoselektiven elektrophilen Cyanierung (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 669-675 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Studies on Stereoselective Electrophiic CyanationThe enantioselective, electrophilic cyanation of the enolates of 2-substituted 1-tetralones 3 is described. Enantiomerically pure 2-cyanato-1,1′-binaphthyl derivatives 2, 6a and b are used as cyanating agents. The influence of solvent, temperature, additives and the method of enolate formation are investigated. Best results are obtained with 48% ee in the case of compound 2 and 60% ee in the case of compound 6b if the enolate is prepared from the corresponding silyl enol ether 7 and Toluene is used as solvent.
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    Masthead (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998) 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400801
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    On the reaction of (S)-trifluoroacetoxysuccinic anhydride with amines to produce hydroxysuccinamic (malamic) acid derivatives (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 733-737 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: L-Malic acid (2) reacts with trifluoroacetic anhydride under anhydrous conditions to give (S)-trifluoroacetoxy-succinic acid anhydride (3). The anhydride 3 undergoes regioselective ring opening with an excess of anilines or primary aliphatic amines leading to N-substituted-(S)-3-hydroxy-succinamic acids (4a-g). Structural elucidation of the reaction products 4a-g was based on analytical and spectroscopic data and on an X-ray structure analysis of 4b. Secondary aliphatic amines react with 3 by condensation and subsequent elimination to furnish N,N′-disubstituted fumaric acid amides 5a, b. Some N-substituted-2-hydroxysuccinamic acids (7a,b) were also prepared for spectral comparison with the 3-hydroxy compounds.
    Additional Material: 1 Ill.
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    B. Fugmann, S. Lang-Fugmann, W. Steglich (Hrsg.), Römpp Lexikon Naturstoffe, 735 S., ca. 280 Tab., ca. 2500 Formeln, geb., Georg Thieme Verlag, Stuttgart - New York, 1997, DM 298,-, sFr265,-, ÖS 2205,-, ISBN 3-13-749901-1 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 487-487 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    URL: http://dx.doi.org/10.1002/prac.19983400516
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    Correction (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 490-490 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400520
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    Chiral polymethine dyes. Part 6.Presented in part at the Third Symposium on Iminium Salts, held at Rechenberg, Germany, September 17-19, 1997 Synthesis, absolute configuration, UV/Vis spectroscopic, and chiroptical properties of Chiral Tri- and Pentamethinium Cyanine Dyes with 1,2,3,4-tetrahydro-3,6-dimethylquinolyl end groups (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 513-529 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Starting with monochiral 1,2,3,4-tetrahydro-3,6-dimethyl quinoline 14a,b, (Schemes 1 and 2), we have synthsized the new chiral, symmetrical and unsymmetrical, tri- and pentamethinium streptocyanine dyes 2a, (Scheme 8), 4a, (Scheme 5), and 5a,b, (Scheme 4), resp. 9a, (Scheme 6), 10a,b, (Scheme 4), and 11a, (Scheme 7) with one or two stereogenic centers in the two heterocyclic end groups. The absolute configuration of 14a,b, and thus the absolute configuration of all monochiral polymethinium dyes derived from 14a,b, has been determined by a single-crystal X-ray analysis of its 4-bromobenzenesulfonyl derivative 17a, (Scheme 1 and Fig. 1). The UV/Vis spectroscopic and chiroptical properties of the new polymethinium dyes have been studied for the first time and compared with that of similar streptocyanine dyes synthesized earlier (Tables 1 and 2) in order to find possible correlations between chiroptical properties and molecular structure.
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    4-Piperidones from Enantiomerically Pure Enones. Synthesis of 6-alkylsubstituted 4-oxo-pipecolic acid derivatives (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 551-556 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cyclization of the enantiomerically pure α,β-unsaturated ketone 1, an aliphatic aldehyde 3 and ammonia or benzylamine gives diastereoselectively cis-piperidones 4/4′. Although only modest yields were obtained, the presented cyclization has the advantage of being a single step reaction. The products 4 can serve as precursors for all-cis-4-hydroxy-piperidones 5 and novel pipecolic acid derivates 9.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/prac.19983400608
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    Novel Potential Enantioselective Phase Transfer Catalysts Based on Lupinine (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 572-575 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ten N-alkylated lupininium derivatives 5-8 were prepared as potential enantioselective phase transfer catalysts. Compounds 5a-d, 6a-d contain four asymmetric centers (including one in the side chain) with known configuration resting on an X-ray structure. Preliminary PT catalytic experiments in several reactions gave high chemical yields but relatively disappointing enantioselectivities.
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    Jura für Chemiker, Eine Orientierungshilfe von Frank J. Hennecke, Handbibliothek Chemie (Herausgeber Wolfgang Düngers), 1. Auflage, 179 Seiten, Hüthig Verlag, Heidelberg, 1997, kartoniert, DM 48,-, ÖS 350,-, SFr 44,50, ISBN 3-7785-2587-5 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 584-584 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    D. C. Harris, Lehrbuch der quantitativen Analyse (Aus dem Amerikanischen von G. Werner, C. Vogt and U. Zeller, Leipzig, übersetzt), Vieweg, Wiesbaden, 4. Auflage, 1178 S., 1998, DM 148,-, ISBN 3-528-06756-X (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 587-587 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400620
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    Effect of Lateral Nitro Groups on the Properties of Sulfur-Ligated Twin Mesogens (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 608-612 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The syntheses and the properties of new sulfurligated liquid crystalline sulfones, containing biphenyl units, as well as the influence of lateral nitro groups on their phase behaviour are described. Differential scanning calorimetry, optical polarizing microscopy and X-ray diffraction measurements reveal liquid crystalline properties for most of the synthesized bis(4-alkoxy-biphenyl-3-yl)sulfones (4). The mesomorphic behaviour of these compounds is compared with that of the corresponding nitro compounds 6. The bis(4-alkoxy-6-nitrobiphenyl-3-yl)sulfones (6) are not mesogenic. The results demonstrate that lateral nitro groups introduced into the biphenyl unit, changing the length-breadth relation, depress the thermal stability and lead to the loss of the mesomorphic properties.
    Additional Material: 3 Ill.
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    Synthesis of components for supramolecules incorporating cycloheptatriene building blocks (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 632-641 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Molecular threads I-III incorporating 1,3,5-cycloheptatriene units have been synthesized by three methods. Bridges were designed as ether (9, 14, 18 and 22), ester (4 and 14) and amino functions (25), respectively, The attachment of a second aryl residue at the seven-membered ring by nucleophilic attack of activated aromatic compounds such as anilines on tropylium salts resulted in the formation of two regioisomers (26 and 27). The macrocycles 28 were formed under high dilution conditions in good yields.
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    Axial Chiral Liquid Crystals-Synthesis of Trisubstituted Allenyl EthersHerrn Prof. Dr. H. Zaschke zum 60. Geburtstag gewidmet (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 662-668 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of racemic and enantiomerical enriched axial chiral liquid crystalline compounds incorporating a trisubstituted allene unit is described. All compounds 16-28 display the smectic C-phase and mostly also a nematic mesophase. All investigated enantiomerically enriched compounds have a ferroelectrically switchable chiral smectic SC*-phase.
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    (Ph3P)2NiX2 (X = Br, Cl) - a mild catalyst for C—C coupling reactions (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 683-685 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Wechselwirkungen in Kristallen. 136. Protonierte Di(pyrid-2-yl)amin-Salze mit verschiedenen Anionen: Monomeres Tetraphenylborat sowie Bis(trifluormethylsulfonat), dimeres Squarat und polymeres Chlorid-Dihydrat (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 722-732 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Interactions in Crystals. 136. Protonated Dipyridylamine Salts with Different Anions: Monomeric Tetraphenylborate as well as Bis(trifluormethylsulfonate), Dimeric Squarate and Polymeric Chloride DihydrateDi(pyrid-2-yl)amine is monoprotonated by acetic, squaric as well as hydrochloric acid and diprotonated by trifluoromethylsulfonic acid. To explore the anion and hydrogen-bridge dependency of its salts, crystals of the monomeric tetraphenylborate, the dimeric squarate as well as the bis(trifluoromethylsulfonate) and the polymeric chloride hydrate have been grown and their structures determined: Separated by bulky tetraphenylborate anions, pyrid-2-yl(2′-pyridinium) amine cation contains an intramolecular hydrogen bridge N⊕H…N and is slightly folded. The squarate salt dimer exhibits additional bridges, N—H…O⊖ and O—H…O. The severely twisted di(2-pyridinium)amine dication is connected to its trifluormethylsulfonate counter anions by altogether three H-bridges, two N⊕H…O and one N—H…O. The chloride dihydrate crystallizes in layers of 16-membered rings, formed from three Cl anions and five water molecules. The diversity of the hydrogen-bridge dominated salt structures is discussed based on comparison with selected literature examples and on PM3 calculations.
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    Reaction of Cyclooctyne with Fischer Carbene Complexes - Synthesis of Tricyclic Quinone Derivatives (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 755-756 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermal reaction of Fischer carbene complexes 1 - 3 with cyclooctyne 4 followed by oxidation with Ce(IV)ammonium nitrate furnished tricyclic quinone derivatives 5 - 7 incorporating an eight-membered ring.
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    Monofunktionalisierte Dendrons verschiedener Generationen - als Reagenzien zur Einführung dendritischer Reste (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 112-121 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monofunctionalized Dendrons of Different Generations - as Reagents for the Introduction of Dendritic SubstituentsIn recent years dendrimers become more and more important not only in organic chemistry. They represent a new class of molecules with unique characteristic features. But dendrimers represent not only designed molecular architecture. They stand for a new concept in chemistry. They can be used to alter the properties of already existing molecular skeletons or they can be used to transfer new properties to a classical functional unit. This means that functionalized dendrimers and dendrons (dendritic building blocks) can be regarded as reagents for the preparation of new compounds with dendritic properties. In this article the synthesis and the practical use of appropriate dendritic reagents is explained. Furthermore we introduce the new technical terms „{n} dendryl-“ for dendritic substituents of n generations and „dendriagent“ which stands for dendritic reagents. Moreover we give a short outlook on future developments.
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    Organic metal-complexes. XXI. Synthesis and structure of 3,5,15,17-tetraoxo-1,7,10,13,19,22-hexaoxa-cyclotetracosane and 2,12,14,24-tetraoxo-4,7,10,16,19,22-hexaoxa-25-mercurato-bicyclo[11.11.1]pentacosane (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 140-150 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new synthesis of the title crown via isoxazolo crown ether 7 and macrocyclic bis-β-eneaminoketone 10 is described. 7 can be synthesized in 14% yield by a non-template double-[3+2] cycloaddition of dinitrileoxide 5 prepared in situ from dinitropolyether 19 by dehydration with Ph-NCO and alkyne 6. The compounds 16, 17 and 18 are synthesized by the same synthetic strategy. Comparable IR and 1H NMR spectroscopic data of macrocyclic and non-cyclic compounds show, that macrocyclic conformation stabilizing effects can be ruled out. The structures of the macrocycles 1, 7, 10 and that of the Hg(II)-complex 25, synthesized by reaction of 1 with Hg(OAc)2 were established by single-crystal X-ray structure analyses. Both inter- and intramolecular hydrogen bonds are observed for the macrocyclic bis-β-eneaminoketone 10, whereas only intramolecular hydrogen bonds are formed by 1.In the Hg(II)-complex of 1 the mercury is bonded to two methylene groups. C—Hg—C is almost linear [177(1)°], the mean Hg—C distance amounts to 215(1) pm. In addition to the Hg—C bonds, each Hg makes a short contact to a carbonyl oxygen in a neighbouring molecule in the plane perpendicular to the C—Hg—C axis [Hg(1)—O(1) = 279(1) pm, Hg(2)—O(5) = 284(1) pm].
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    Total synthesis of angucyclines. 9. An Alternative Biomimetic-Type Synthesis of 8-Deoxytetrangomycin (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 171-174 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Base-catalyzed cyclization of the naphthoquinone 5 afforded the 1,2-dihydroanthraquinone 6a. The bisalkylation products 9 and 10 were obtained by Stille-type chain elongation of the corresponding triflate 6b with the stannanes 7 or 8. The dihydroanthraquinone 9 is a potential precursor for the SS-228 Y-type angucyclinones, where as the diketone 10 can be converted to 8-deoxytetrangomycin (11).
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    (Diacetoxyiodo)benzene DIB - a Multitalented Oxidant in Organic Synthesis (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 184-186 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    URL: http://dx.doi.org/10.1002/prac.19983400215
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    A Practical Synthesis of the Cyclohexyl Part of the Immunosuppressant FK506 (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 656-661 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Starting from the benzylidene lactone 3 of D-(-)-quinic acid the cyclohexyl fragment 15 (C-28-C-34 part) of the immunosuppressant FK506 was synthesized. Key steps include homolytic deoxygenation reactions on compounds 4 and 6 as well as a regioselective opening of the benzylidene acetal 5. Opening of the lactone 7 to provide the methyl ester 8 was followed by methylation of the hydroxy group to give 9. Further steps provided the aldehyde 12 which was elongated to the alkyne 15. This sequence provides 15 in gram quantities.
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    Trimethylsilyldiazomethane (TMS-CHN2) and lithiated trimethylsilydiazomethane - versatile substitutes for diazomethane (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 679-682 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400714
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    Bezugselektroden für elektrochemische Messungen (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 710-721 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reference Electrodes for Electrochemical MeasurementsRecent advances in the development of reference electrodes for amperometric and voltammetric measurements are reviewed. The suitability of all-solid-state electrodes as reference electrodes for pH measurement for use with an glass electrode and for other potentiometric measurements is evaluated. The role of new technologies, as thick film and as thin film technology, are discussed. References for microelectrodes are represented.
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    Erweiterte Konjugation in unsymmetrischen Stilbenylsquarainen (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 744-754 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Extended Conjugation in StilbenylsquarainesUnsymmetrical 1-aryl-3-stilbenylsquaraines 2a-e and 1,3-bis(stilbenyl)squaraines 3a-c were prepared by CC coupling reactions of the corresponding substituted arenes with derivatives of squaric acid (Schemes 2 and 3). Dialkylamino and alkoxy groups enhance the solubility of these dyes and enlarge the intramolecular charge transfer of these donor-acceptor-donor systems. The extended conjugation of the stilbene units - in comparison with arene building blocks - leads to significant bathochromic shifts in the Vis/NIR absorption spectra.
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    Goethe und die frühen chemischen JournaleDieser Beitrag wurde sowohl aus Anlaß des 250. Geburtstages von J. W. Goethe als auch zur 200jährigen Geschichte des Journals für Praktische Chemie und seiner Vorläufer geschrieben. (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 764-770 
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    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Goethe and the Earlier Chemical JournalsTwo hundred years ago the german “Allgemeines Journal der Chemie” was founded by the Bergrat Scherer from Weimar. His redaction was situated in the castle Belvedere. Goethe was a promoter of this chemist und editor. The concept of this journal, the citations of Goethe and his works in the following “Journal für Chemie und Physik”, edited by Schweigger, and the interests of Goethe as reader also on Crells oldest chemical journal from 1778 are described in detail.
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    Enantiomeric separation of rac-indoprofen by a biocatalytic procedure (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 321-324 
    Details
    ISSN: 0899-0042
    Keywords: NSAID ; esterification ; resolution ; Candida antarctica lipase ; rac-Indoprofen ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Lipase from Candida antarctica, commercially available immobilised on acrylic resin as Novozym® 435, allows for enantioselective esterification of rac-indoprofen (±)-1, with methanol in a dioxane-toluene solvent system. A double esterification process affords methyl ester (-)-(R)-2 in 85% e.e. and enantiopure (+)-(S)-1, both in good chemical yield. Chirality 10:321-324, 1998. © 1998 Wiley-Liss, Inc.
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    Determination of the rotational barriers of atropisomeric polychlorinated biphenyls (PCBs) by a novel stopped-flow multidimensional gas chromatographic technique (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 316-320 
    Details
    ISSN: 0899-0042
    Keywords: atropisomeric polychlorinated biphenyls (PCBs) ; Chirasil-Dex ; rotational barrier ; stopped-flow multidimensional gas chromatographic technique ; on-line enantiomerization kinetics ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rotational barriers ΔG
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    Discrimination in resolving systems. III: Pseudoephedrine-mandelic acid (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 325-337 
    Details
    ISSN: 0899-0042
    Keywords: diastereomeric salts ; molecular recognition ; hydrogen bonding ; thermal analysis ; crystallography ; solubility ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (+)-(1S;2S)-Pseudoephedrine and racemic mandelic acid form three distinct diastereomeric salts from solutions in 95% ethanol. The least-soluble phase, a hemihydrate, contains the (2R)-mandelate. A salt phase of intermediate solubility is the unsolvated double salt, containing both the (2R)- and the (2S)-mandelate. The most-soluble salt phase contains the (2S)-mandelate. Mandelate configuration and order of solubility (based on the heats of fusion) is inverted from that found in the same system synthesized from chiral base and acid, and then crystallized from benzene solution. The (2R)-mandelate hemihydrate (-H2O at 349.5K, mp 391K), monoclinic, P21, a = 6.788(5), b = 29.415(35), c = 9.488(10)Å, β = 108.91(8)°, Z = 4 (2 ion-pairs/asymmetric unit). Intermediate double salt (2S)- and (2R)-mandelate, mp 377.6K, anorthic, P1, a = 7.758(4), b = 9.966(5), c = 13.366(6)Å, α = 72.99(4), β = 79.98(4), γ = 70.51(4)°, Z = 1 (2 ion-pairs/asymmetric unit). The (2S)-mandelate (mp 386.2K), orthorhombic, P212121, a = 7.079(6), b = 13.443(10), c = 18.820(14)Å, Z = 4 is identical to a salt made from a combination of enantiomeric moieties from benzene solution. While differing from ephedrine mandelates in configuration at one center, solubilities of pseudoephedrine mandelates in 95% ethanol are much larger. A comparison of molecular structure (non-polar and H-bonding) regions of pseudoephedrine and ephedrine mandelates shows similarities and differences that are tentatively linked to crystal properties. This study reemphasizes the necessity for consistency in solvent use in resolution and in phase identification and comparison because the phases produced are frequently dependent upon the solvent. Chirality 10:325-337, 1998. © 1998 Wiley-Liss, Inc.
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    Manipulation of chiral resolution for isoxazoline-based IIb/IIIa receptor antagonists using various mobile phase additives in subcritical fluid chromatography (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 338-342 
    Details
    ISSN: 0899-0042
    Keywords: additive ; selectivity ; efficiency ; modifier ; subcritical fluid chromatography ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Subcritical fluid chromatography (SubFC) using a carbon dioxide-methanol mobile phase is used for the chiral resolution of IIb/IIIa receptor antagonist enantiomers. The chiral resolution of three analogs, each containing two chiral centers, is optimized using various mobile phase additives. The effects that acidic, basic, and neutral additives have on retention, efficiency, and resolution are examined. The additive that gives the best resolution was found to be dependent upon the functionality and charge of the chiral analyte. For charged analytes, additives that act as competing ions of the same charge as the chiral analyte dramatically improve efficiency and resolution. Resolution of neutral chiral analyte enantiomers is also greatly affected by the choice of mobile phase additive. Chirality 10:338-342, 1998. © 1998 Wiley-Liss, Inc.
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    Mechanism of chiral asymmetry generation by chiral autocatalysis in the preparation of chiral octahedral cobalt complex (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 343-348 
    Details
    ISSN: 0899-0042
    Keywords: chiral asymmetry generation ; chiral autocatalysis ; primary nucleation ; secondary nucleation ; chiral cobalt complex ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chiral asymmetry generation, the predominant production of one enantiomer in a non-chiral environment, could occur in the production of the chiral complex cis-[CoBr(NH3)(en)2]Br2 by the reaction of [Co(H2O)2{(OH)2Co(en)2}2](SO4)2 with ammonium bromide in an aqueous medium. The main kinetic steps in the reaction system have been determined. During the reaction, the product crystallizes at an early stage. When a very small amount of crystalline enantiomer was added to the reaction system at an early stage, the same enantiomer was produced preferentially; in addition, the enantiomeric excess of the product increased with increasing the stirring rate. Thus, it seems that each enantiomer generates chiral crystals that could self-replicate through secondary nucleation when the solution is stirred; these crystals in turn enhance the production of the same enantiomer. With a computer code that simulates such a kinetic mechanism, it is shown that enantiomeric excess observed in the experiments could be reproduced. Chirality 10:343-348, 1998. © 1998 Wiley-Liss, Inc.
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    Determination of the enantiomeric purity of commercial Jacobsen's catalyst samples (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 362-363 
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    ISSN: 0899-0042
    Keywords: Jacobsen's catalyst ; enantiomeric purity determination ; chiral HPLC ; cyclodextrin chiral stationary phases ; enantioseparation ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A HPLC method is described for the chiral analysis of the commercially available Jacobsen's catalyst. A hydroxypropyl β-cyclodextrin stationary phase was used in conjunction with a nonaqueous, polar-organic mobile phase. The method can be applied to control the enantiomeric purity of the catalyst, which is of great importance for quality control of that product. High accuracy in the determination of trace levels of the unwanted enantiomer in the presence of large amounts of the desired enantiomer is demonstrated. Chirality 10:362-363, 1998. © 1998 Wiley-Liss, Inc.
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    Stereoselective renal secretion of carbenicillin in rabbits: Role of the organic anion transporter at the renal brush border membrane (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 349-357 
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    ISSN: 0899-0042
    Keywords: carbenicillin ; stereoselective ; secretion ; transport ; rabbit ; membrane vesicles ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Stereoselectivity in the renal secretion of carbenicillin (CBPC) was studied in rabbits. Significant renal secretion of CBPC was observed in vivo, with the secretion of the S-epimer being greater than that of the R-epimer. Stereoselective transport of CBPC was further studied in vitro using basolateral and brush border membrane vesicles prepared from rabbit kidneys. The transport of CBPC by the organic anion transporter into the basolateral membrane vesicles (BLMV) was not stereoselective. In contrast, a distinct stereoselectivity was observed in the transport of CBPC by the organic anion transporter into the brush border membrane vesicles (BBMV), with the transport of the S-epimer being more favorable. Significant epimer-epimer interactions were also observed in the transport into BBMV. The stereoselectivity of the transport of CBPC was calculated from the kinetic parameters with consideration of epimer-epimer interactions and was similar to that observed in vivo. It was concluded that the observed stereoselectivity in the renal secretion of CBPC in vivo reflected that of transport via the organic anion transporter located at the brush border membrane. Chirality 10:349-357, 1998. © 1998 Wiley-Liss, Inc.
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    Enantiomeric separation of several cyclic imides on a macrocyclic antibiotic (vancomycin) chiral stationary phase under normal and reversed phase conditions (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 358-361 
    Details
    ISSN: 0899-0042
    Keywords: cyclic imides ; barbiturates ; piperidine-2,6-diones ; mephenytoin ; chiral recognition ; enantioselectivity ; vancomycin chiral stationary phase ; normal-phase mode ; reversed-phase mode ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several cyclic imidic compounds (barbiturates, piperidine-2,6-diones, and mephenytoin) are enantiomerically resolved via high-performance liquid chromatography (HPLC) on a macrocyclic antibiotic covalently bonded to a silica gel support. The Chirobiotic V chiral stationary phase (CSP) column contains the antibiotic vancomycin as the chiral selector. The results of the analysis show that the substituents at the chiral carbon position of the racemic drugs affect chiral resolution. In addition, ring size may also play a role when considering the formation of analyte-CSP inclusion complexes. Contrary to the piperidine-2,6-diones, the chromatographic parameters for the barbiturates are much the same under normal- or reversed-phase conditions. The details of these results are discussed. Chirality 10:358-361, 1998. © 1998 Wiley-Liss, Inc.
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    Emanuel Gil-Av honorary issue of Chirality (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 371-372 
    Details
    ISSN: 0899-0042
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    A closer study of chiral retention mechanisms (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 375-381 
    Details
    ISSN: 0899-0042
    Keywords: retention mechanisms ; separation of enantiomers ; chiral stationary phases ; equilibrium isotherms ; bonding ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The retention mechanisms and the separation of enantiomers on the classes of chiral stationary phases which are made by bonding isolated groups on the surface of an adsorbent are discussed. It is shown that retention on these phases originates from mixed mechanisms and how the individual contributions of these two mechanisms can be separated, by determining and modeling the equilibrium isotherms. A contribution originating from interactions of the isomers with the nonselective sites (type-I) and another one due to interactions with the enantioselective sites (type-II) can be determined and their importance studied as a function of several parameters, e.g., temperature or pH. This approach is illustrated with results obtained with different pairs of enantiomers on bovine serum albumin, 4-methylcellulose tribenzoate, or cellobiohydrolase immobilized on silica. Chirality 10:375-381, 1998. © 1998 Wiley-Liss, Inc.
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    Amphiphilic proline and prolylproline derivatives in the rhodium(I)-catalyzed asymmetric hydrogenation in water: Chiral induction as indication of the location of reactants within the micelle (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 754-759 
    Details
    ISSN: 0899-0042
    Keywords: solubilization ; enhanced enantioselectivity ; chiral induction ; critical micellar concentration ; reaction place ; function of proline ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Proline and prolylproline dipeptide derived surfactants promote the asymmetric hydrogenation of (Z)-methyl α-acetamidocinnamate in water in the presence of the catalytic system [Rh(cod)2]BF4 + BPPM. Activity and enantioselectivity are enhanced significantly and the results in water are similar to those obtained with organic solvents. The possibility of a chiral induction was investigated in the presence of the optically active amino acid and peptide amphiphiles and an achiral rhodium catalyst [Rh(bdpb)(cod)]BF4. The analysis of the low optical induction gave some indications of the site where the reaction takes place within the micelle. Selected critical micelle concentrations (cmc) of the new prepared surfactants were determined by surface tension measurements. Chirality 10:754-759, 1998. © 1998 Wiley-Liss, Inc.
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    Synthesis of racemic and optically active glycidic ethers, precursors of liquid crystalline polyethers (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 779-785 
    Details
    ISSN: 0899-0042
    Keywords: optically active oxiranes ; liquid crystals ; epichlorohydrin ; glycidol ; chiral HPLC ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of racemic and optically active oxiranes, bearing mesogenic groups, precursors of liquid crystalline polyethers, has been synthesized from epichlorohydrin or glycidol. The enantiomeric excess of the optically active oxiranes has been determined by chiral stationary phase HPLC. Compounds bearing 4-cyanobiphenyl mesogenic group exhibit monotropic liquid crystalline behavior. A transfer of chirality to the mesophase has been observed for the optically active oxiranes, which present a cholesteric phase. Chirality 10:779-785, 1998. © 1998 Wiley-Liss, Inc.
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    Chiral separation of some 4a-methyl-1,2,3,4,4a,9a-hexahydro-fluoren-9-one derivatives as a probe for difference in solvation by 2-propanol of carbamate moiety in chiralcel OD-H, chiralpak AD, and chiralpak AS chiral stationary phases (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 770-777 
    Details
    ISSN: 0899-0042
    Keywords: chiral HPLC ; principal component analysis (PCA) ; hierarchical clustering ; hydrogen bonding ability ; solvation of carbamate phases ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chromatographic resolution of 12 derivatives in the 4a-methyl-2,3,4,4a-tetrahydro-1H-fluorene and 4a-methyl-1,2,3,4,4a,9a-hexahydrofluoren-9-one series differing by the framework around position 9 and substitution in position 6, are reported on Chiralcel OD, Chiralpak AD, and Chiralpak AS under two elution conditions and according to the two classes of enantiomers. Results from principal component analysis (PCA) as well as hierarchical clustering show a clustering of the actual compounds depending on properties around position 9, the effect of the substituent in position 6 (methyl, chloro or fluoro) not being strong enough to intermesh the data. Carbamate phases show very different properties when they are used in the separation of a series of ketones C and α-chloroketones D, which differ in basicity and the steric requirement around the carbonyl. Analysis of the effect of 2-PrOH content in hexane on the retention is consistent with a large difference in solvation of the carbamate moiety by 2-PrOH, in the order Chiralcel OD 〉 Chiralpak AD 〉 Chiralpak AS. 4a-Methyl-2,3,4,4a-tetrahydro-1H-fluorene derivatives, which lack hydrogen bonding sites, are not discriminated on these CSPs and show identical k′ responses to 2-PrOH content changes on the three CSPs. Chirality 10:770-777, 1998. © 1998 Wiley-Liss, Inc.
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  • 98
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    Enantiodifferentiation of four γ-lactones produced by Penicillium Roqueforti (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 786-790 
    Details
    ISSN: 0899-0042
    Keywords: enantioseparation ; peach-like aroma ; fatty acid bioconversion ; gas chromatography-mass spectrometry in selected ion monitoring mode ; Penicillium roqueforti ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Identification and enantiodifferentiation of γ-lactones produced during the bioconversion of soy bean fatty acids by Penicillium roqueforti spores in the presence of an exogenous lipase was performed using gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode. It was shown that 4-dodecanolide and 4-hexanolide were first produced with an enantiomeric excess (99%) in favor of the (R) form, whereas an enantiomeric excess in favor of the (S) form (94%) is found for (6Z)-dodecen-4-olide, the major lactone produced by the fungus. If incubation was continued, mixtures of both enantiomers were found, more particularly for 4-decanolide (R/S:40/60), which was produced only after 120 hr of incubation. The results obtained can be explained by the stereoselective hydroxylation by a 10-hydratase and/or a 10-lipoxygenase of the unsaturated fatty acid precursors, oleic and linoleic acids, and by competition between different pathways. The results point out the limitations of chiral GC analysis as a criterion for the natural origin of relevant lactones, and the complexity of mechanisms involved in γ-lactone formation by microorganisms. Chirality 10:786-790, 1998. © 1998 Wiley-Liss, Inc.
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    Separation of (R)- and (S)-tert-butyl 2-tert-butyl-4-methoxy-2,5-dihydro-1,3-imidazole-1-carboxylate (building block for amino acid synthesis) by preparative high performance liquid chromatography on a polysaccharide stationary phase (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 217-222 
    Details
    ISSN: 0899-0042
    Keywords: amylose ; 3,5-dimethylphenyl-carbamate ; polysaccharide phase ; tert-butyl 2-tert-butyl-4-methoxy-2,5-dihydro-1,3-imidazole-1-carboxylate; amino acid ester synthesis ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparative separation of the enantiomers of the title compound, a versatile chiral building block for the synthesis of unnatural amino acid esters, by high performance liquid chromatography on a chiral stationary phase (CSP), is reported for the first time. The CSP consists of amylose-(3,5-dimethylphenyl-carbamate), which has been coated onto the surface of macroporous aminopropyl-functionalized silica gel. The effect of mobile phase composition and the amount of amylose derivative on the silica gel has been thoroughly investigated. Using 2-propanol as organic modifier in hexane as mobile phase, on a semi-preparative column (200 mm × 40 mm ID, containing 192 g of stationary phase) about 200 mg of the racemate was separated per injection. Running the equipment under automatic conditions with repetitive injection mode allowed for the separation of 30 g per day. Both enantiomers were obtained with enantiopurities 〉99.75:0.25. Chirality 10:217-222, 1998. © 1998 Wiley-Liss, Inc.
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    Mechanistic aspects of the biogenesis of rose oxide in Pelargonium graveolens L'Héritier (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 10 (1998), S. 229-237 
    Details
    ISSN: 0899-0042
    Keywords: deuterium labelling ; menthocitronellol ; citronellol ; enantioselective multidimensional gas chromatography-mass spectrometry (enantio-MDGC-MS) ; dynamic headspace analysis ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Mechanistic aspects of the biogenesis of the chiral monoterpenoid rose oxide in Pelargonium graveolens L'Héritier are investigated using deuterium-labelled precursors. After administration of the precursors using the cut-stem method, the dynamic headspace extracts of the plants are analysed using multidimensional gas chromatography-mass spectrometry (enantio-MDGC-MS). It is unequivocally shown that this plant is able to convert citronellol and menthocitronellol into cis-/trans-rose oxide. Menthocitronellol is converted into rose oxide with a clearly detectable enantiodiscrimination. These facts may be explained with the presence of an oxidase, which is able to oxidize citronellol and menthocitronellol in allylic position. A photooxygenation mechanism including singlet oxygen as the oxidizing agent is rather unlikely. Chirality 10:229-237, 1998. © 1998 Wiley-Liss, Inc.
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