3?-De-O-methyl-2?,3?-anhydro-lankamycin, a New Macrolide Antibiotic fromStreptomyces violaceoniger

A further examination of the products from fermentation broths of Streptomyces violaceoniger has yielded small quantities of several lankamycin related antibiotics and metabolites. One of the antibiotics has been characterized as 3″-de-O-methyl-2″,3″-anhydro-lankamycin. The anhydro sugar of the new lankamycin, 3-methyl-4-O-acetyl-2,3,6-trideoxy-α-L-threo-hex-2-enepyranoside was also isolated as the ethyl glycoside from fermentation broths of the same organism.