Concanamycin A,8-deethyl-8-methyl- Concanamycin B MCH 210 NSC670977 Oxacyclooctadeca-3,5,13,15-tetraen-2-one, 18-[(1S,2R,3S)-3-[(2R,4R,5S,6R)-4-[[4-O-(aminocarbonyl)- 2,6-dideoxy-.beta.-D-arabino-hexopyranosyl]oxy]tetrahydro- 2-hydroxy-5-methyl-6-(1E)-1-propenyl-2H-pyran-2-yl]- 2-hydroxy-1-methylbutyl]-8,10-dihydroxy-3,17-dimethoxy- 5,7,9,11,13-pentamethyl-, (3Z,5E,7R,8R,9S,10S,11R,13E,15E,17S,18R)-