New Macrodiolide Antibiotics, 11-O-Monomethyl- and 11,11‘-O-Dimethylelaiophylins, from Streptomyces sp. HKI-0113 and HKI-0114

Elaiophylin (1) and two new methyl derivatives, 11-O-monomethylelaiophylin (2) and 11,11'-O-dimethylelaiophylin (3), were isolated from the mycelium cake of Streptomyces strains HKI-0113 and HKI-0114. The structures of 2 and 3 were determined by mass spectrometric and NMR investigations. Compounds 2 and 3 display antimicrobial and moderate cytotoxic activities.