ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 12 (1998), S. 67-75 
    ISSN: 0268-2605
    Keywords: organotin ; tributyltin ; tributyltin oxide ; tetrabutyltin ; degradation ; bioassay ; bioindicator ; Chemistry ; Industrial Chemistry and Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The growth response of the alga Chlorella kessleri and the euglenoid Euglena gracilis has been studied as a model system to determine the effects of a tin salt (SnCl4·5H2O) and of some organotin (OT) derivatives, namely tetrabutyltin (TeBT), tributyltin (TBT) and tributyltin oxide (TBTO). Abiotic degradation was studied as well. Cells were exposed to a toxicity series (0-50 μg/mL-1) for the four chemicals in seven-day bioassays. Both microorganisms are tolerant of the inorganic salt, but growth inhibition was significant for all OT compounds, and especially large for TBT and TBTO. Although C. kessleri and E. gracilis are known to be tolerant towards metals and organic chemicals, the present results show that both are sensitive to organotin compounds: the inhibition of the growth was greater for C. kessleri. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 13 (1978), S. 61-64 
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The electron impact induced fragmentation of chlorine substituted o-aminobenzophenones has been examined. All the compounds show ions formed by α-cleavage on either side of the carbonyl group. The relative intensity of the resulting ions is predictable from the quasi-equilibrium theory. The most important features of the mass spectra of these compounds are, however, intense [M—H]+ ions for the primary amines and [M - OH]+ ions for the N-methylated compounds. These and other less intense peaks as well as some metastable ions allows structural elucidation.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 33 (1995), S. 717-725 
    ISSN: 0887-624X
    Keywords: biodegradable polymers ; polyanhydride ; fatty acid ester ; ricinoleic acid ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new class of polyanhydrides synthesized from nonlinear hydrophobic fatty acid esters, based on ricinoleic, maleic acid, and sebacic acid, possessed desired physico-chemical and mechanical properties for use as drug carriers. The polymers were synthesized by melt condensation to yield film-forming polymers with molecular weights exceeding 100,000. Their rate of elimination from rats in the course of about 2 months was faster than that found for similar polyanhydrides previously tested. In vitro studies showed that these polymers underwent rapid degradation in the first 10 days. The drug release followed first-order kinetics, showing a rapid drug release rate in the first 10 days which correlated with the degradation of the polymers. The fatty acid ester monomers underwent in vitro enzymatic degradation to the natural starting acids. Tests in rats demonstrated their toxicological inertness and biodegradability. © 1995 John Wiley & Sons, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 0894-3230
    Keywords: phenyllithium ; E-cinnamaldehyde ; organolithium ; addition ; mechanism ; Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The reaction of phenyllithium (PhLi) with E-cinnamaldehyde (1) has been fully examined. Besides the main product E-1,3-diphenyl-2-propen-1-ol (2), three other by-products were detected: E-cinnamyl alcohol (3), E-chalcone (4) and E-1,3-diphenylpropanone (5). The effect of several variables on the nature and relative yields of products was examined. In all the solvents studied, the selectivity of the reaction was higher at higher temperatures, probably owing to aggregation effects; at lower temperatures the reaction is slower and the amount of by-products increases. The addition is complete in 1 h at 0 °C in THF for a [PhLi]:[1] ratio of 1:1, and longer reaction times have almost no effect, while for the reaction in toluene the amount of by-products increases when the reaction mixture is allowed to stand. The concentration of the reagents has no important effect on the reaction as long as the ratio is kept equal to 1:1. The influence of light was examined and a marked decrease in the selectivity of the reaction was observed. When the reaction was carried out in the presence of radical traps, no by-products were detected. Finally, for a [PhLi]:[1] ratio of 3:1 the main product is the dihydrochalcone 5, especially for long reaction times. All the above results could be interpreted in a reaction scheme involving electron transfer from PhLi to 1, and further reaction of the radical ions formed as well as reaction of dimeric PhLi without previous deaggregation when the ratio is 3:1.­© 1998 John Wiley & Sons, Ltd.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 10 (1997), S. 97-106 
    ISSN: 0894-3230
    Keywords: 2-amino-5-chlorobenzophenone ; hydrochloric acid ; kinetics ; Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: ---The reaction of 2-amino-5-chlorobenzophenone (1) with 0·5-2 M HCl was studied in 1:1 (v/v) MeOH-H2O at 60 and 80 °C. Products that were isolated were characterized as 2-(N-methylamino-5-chlorobenzophenone) (2), 2- amino-3,5-dichlorobenzophenone (3), 2-N-methylamino-3,5-dichlorobenzophenone (4), 2-(N,N)-dimethylamino-5- chlorobenzophenone (5), 2,4-dichloro-10-methyl-9,10-acridinone (6) and 2,4-dichloro-9,10-acridinone (7). The rates of reaction of 1 and the rates of formation of 2-5 were measured at several HCl concentrations. The methyl transfers, the chlorination and the cyclization reactions that give rise to 2-7 were unexpected under the present reaction conditions. A set of differential equations was proposed in order to calculate the rate constants for each step of this complex reaction. The proposed reaction scheme also takes into account the reaction 2→1 and permits the calculation of the rate constants for this reversible reaction. The experimental values of the rate constants for reaction of 1 were compared with those for 2 under the same reaction conditions, in order to evaluate the importance of the methyl group on the methyl transfer reactions; it was found that the methyl group is not required for the unexpected reaction to occur. © 1997 by John Wiley & Sons, Ltd.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 10 (1997), S. 233-241 
    ISSN: 0894-3230
    Keywords: surface effects ; radical anions ; benzoyl radical ; coupling of radicals ; surface catalysis ; electron transfer ; reactions in the double laye ; Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Benzaldehyde in THF reacts with lithium metal to give the expected reduction product, benzyl alcohol, plus benzoin and benzyl as minor products. The kinetics of the overall reaction as well as the partial rate coefficients of the several steps have been determined under various reaction conditions. It was found that adsorption on the surface and electron transfer from the lithium to benzaldehyde are the slow steps. The experimental results show interesting surface effects, and evidence for significant radical intermediates, which were characterized by their epr spectra and trapping experiments, results useful to gain insight into the mechanisms of these and other related reactions. © 1997 John Wiley & Sons, Ltd.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 2000 (2000), S. 645-655 
    ISSN: 1434-193X
    Keywords: INOC ; Pyrrolidines ; Piperidines ; Stereoselective synthesis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Intramolecular nitrile oxide olefin cycloaddition (INOC) reactions of oximes 1-3 and of 24-27 derived from L-amino acids have been found to proceed stereoselectively, yielding tricyclic fused pyrrolidines and piperidines. Further manipulation led to chiral hydroxymethyl-substituted fused piperidines 33-35 and to 3-amino-4-(1-hydroxypropyl)-2-mercaptomethyl-N-methylpiperidine (36). The structures and stereochemistries of the fused systems, as well as those of the piperidines, have been established by NMR.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 24 (1986), S. 507-511 
    ISSN: 0749-1581
    Keywords: Nitropyridines ; Nitrobenzenes ; 1H and 13C NMR ; Hydrogen bonding ; Conformation MS ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 1H and 13C NMR spectra of 3-nitro-, 5-nitro- and 3,5-dinitro-2-methoxypyridines have been determined. The results show the preferred cis conformation for the 2-methoxy group, and the importance of steric repulsion between the oxygen atom of this group and those of the o-nitro group which hinders conjugation in the 3-nitro-substituted derivatives. Similar steric inhibition of resonance is observable with 2-N-butylamine-, 2-N-cyclohexylamine- and 2-(N-piperidyl)-substituted nitropyridines, whose 1H and 13C NMR spectra were also determined. In the case of the secondary amines, a hydrogen bond between the amino proton and the 3-nitro group was clearly detected. 1H and 13C NMR spectra of 2,6-dinitro-, 2,4-dinitro- and 2,4,6-trinitro-2-R-benzenes (R = OCH3, NHC4H9, NH-cyclo-C6H11, NC5H10) were also recorded and compared with those of the pyridine derivatives. The electronic aza and nitro group effects are comparable if conjugation of the nitro group is not hindered.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 0570-0833
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...