Marine Natural Products. XXXVIII. Absolute Stereostructures of Altohyrtins A, B, and C and 5-Desacetylaltohyrtin A, Potent Cytotoxic Macrolides, from the Okinawan Marine Sponge Hyrtios altum

抄録

Altohyrtins A (1), B (2), and C (3) and 5-desacetylaltohyrtin A (4), extremely potent cytotoxic macrolides, have been isolated from the Okinawan marine sponge Hyrtios altum. The absolute stereostructures of these macrolides have been elucidated on the bases of detailed NMR analysis, application of the modified α-methoxy-α-(trifluoromethyl)phenylacetic acid (MTPA) method to the hexa-MTPA esters, and application of the circular dichroism (CD) exciton chirality method.