Stoffwechselprodukte von Mikroorganismen. 178. Mitteilung . Die Avilamycine A und C: Chemischer Abbau und spektroskopische Untersuchungen

Hydrolysis and methanolysis of Avilamycin C yielded a series of mono‐ and oligosaccharide‐like products, which were, with one exception, identical with degradation products of flambamycin. Instead of evalose (6‐deoxy‐3‐methyl‐ D ‐mannose), a building stone of Flambamycin and Everninomicin B, evermicose (2, 6‐dideoxy‐3‐methyl‐ D ‐mannose) was identified as a constituent of the Avilamycins. This sugar was known as a degradation product of the Everninomicins C and D. From the degradation results a structure of Avilamycin A was postulated which differs from that of Flambamycin only by the lack of a hydroxyl group in position 2 of the evalose residue. This hypothesis was confirmed by a careful 1 H‐ and 13 C‐NMR. study.