ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
On the Structure Elucidation of Niphimycin, Part I. Purification and Characterization of the Niphimycins Iα and Ib̃; Degradation by Nitric AcidFrom a sample of niphimycin the pure components, niphimycin Iα and Ib̃, were isolated by column chromatography and droplet counter-current chromatography. They were characterized by UV., IR., 1H-NMR. (300 MHz) and 13C-NMR. spectra. A vigorous degradation of niphimycin with nitric acid, followed by esterification with diazomethane, gave a complex mixture, from which many components could be isolated and identified. Several of the degradation products were synthesized, one of them (dimethyl 2,4-dimethyladipate) in a stereospecific manner, establishing the configuration of two of the centers of chirality of niphimycin.Niphithricin was identified with copiamycin and yielded with nitric acid a degradation mixture very similar to that from niphimycin. The structures of the degradation products are in good agreement with a macrolide-type structure of niphimycin and copiamycin.Further work for structure elucidation of niphimycin and copiamycin is in progress.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19830660111
Permalink