Dactylocyclines, novel tetracycline derivatives produced by a Dactylosporangium sp. III. Absolute stereochemistry of the dactylocyclines.
نویسندگان
چکیده
The dactylocycline antibiotics were found through circular dichroism measurements, NMR spectroscopy and chemical transformations to possess the usual tetracycline family absolute configuration at carbons 4, 4a, 5a and 12a. The absolute stereochemistry about the C-6 carbon, however, was the reverse of that found with previously investigated tetracyclines.
منابع مشابه
Dactylocyclines, novel tetracycline derivatives produced by a Dactylosporangium sp. II. Structure elucidation.
Fermentation of Dactylosporangium sp. (ATCC 53693) produces a mixture of tetracycline derivatives from which several related tetracycline glycosides, the dactylocyclines, were isolated and their structures determined. The most abundant glycoside in initial fermentations was found to be dactylocycline A. Each glycoside proved to be acid sensitive and readily hydrolyzed to a common aglycone, dact...
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عنوان ژورنال:
- The Journal of antibiotics
دوره 45 12 شماره
صفحات -
تاریخ انتشار 1992