Elsamicins A and B, New Antitumor Antibiotics Related to Chartreusin. 2. Structures of Elsamicins A and B

Article abstract of DOI:10.1021/jo00382a005

The structures of new antitumor antibiotics elsamicins A (1a) and B (1b), produced by an unidentified actinomycete strain J907-21, have been established by a combination of chemical degradation, spectral analysis, and X-ray diffraction.They are structurally similar to chartreusin containing chartarin as an aglycon, but differ to each other in sugar moieties.Elsamicin A possesses two novel sugars, 2-amino-2,6-dideoxy-3-O-methyl-D-galactose and 6-deoxy-3-C-methyl-D-galactose.The presence of the amino sugar makes elsamicin A remarkably water-soluble and more bioactive than chartreusin.Elsamicin B differs from elsamicin A in that it lacks the amino sugar moiety.