[Aglycone structure of the polyene antibiotic, gannibamycin].

Functional analysis of gannibamycin, a new macrolide pentaenic antibiotic was performed. It was found that the antibiotic contained carbonyl, carboxyl group and one molecule of nitrogen and no isolated double bonds. The antibiotic did not participate in the reaction of retroaldol splitting. Ozonization of the antibiotic followed by reduction of the ozonolysis products at first by catalytic hydrogenation and then by lithium aluminohydride resulted in formation of polyols, such as 14-hydroxymethyloctadecanhexaol-1, 6, 13, 15, 17, 18 and 2-methyl-1, 4, 6-trihydroxyoctane. Their structures were proved with mass spectrometry of peracetates. 3-Methyl-tetradecanedicarboxylic acid was isolated from the oxidation products of perhydrogannibamycin. Partial structure of the aglycone, i. e. 1, 30 (or 1, 32)-lactone 13, 15, 17, 30, 32-pentohydroxy-28-methyl-6-ketotetratricontane-18, 20, 22, 24, 26-pentaen-1, 14-dicarboxylic acid was suggested. It was confirmed by the analysis of the mass spectra of the antibiotic permethoxy derivative and its deutero analog.