ISSN:
0947-3440
Keywords:
Antibiotics
;
Sannamycin-type
;
Mirror-images
;
Syntheses
;
Activity, biological
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Sets of variously protected purpurosamine/2-epi-purpurosamine-type glycosyl donors (O-acetates) and sannamine-type glycosyl acceptors were coupled as racemates and pure enantiomers, according to a modified Koenigs-Knorr procedure with TMSOTf as promotor. The α anomers isolated from the respective mixtures of glycosides (yields varying between 51% and 91%, α:β anomeric ratios between 1.5:1 and 13:1, α:α′ diastereomeric ratios between 1:1 and 1:1.5) were transformed through standard protection/deprotection and glycidation measures into 6′-des(N-methyl)sannamycins A (1, 1′, 2, 2′) and B (37, 37′), 2′-epi-6′-des(N-methyl)sannamycins (3, 3′), the enantiomeric sannamycins A and B (ent-4)/ (ent-40), the diastereomers (ent-4′)/(ent-40′), and the enantiomeric 2′-epi-sannamycin A (ent-5)/(ent-β-5). For one of the fluorinated glycosides (α-26′), featuring a somewhat unusual aglycon conformation, an X-ray structural analysis was performed. In explorative biological tests, the naturally configurated glycosides 1 and 3 showed limited, 2 a rather broad activity against a number of pathogenic microorganisms. Yet, none of the glycosides with non-natural configuration was found to be active.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.199519950239
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