Amidepsines, Inhibitors of Diacylglycerol Acyltransferase Produced by Humicola sp. FO-2942. II. Structure Elucidation of Amidepsines A, B and C.

Structures of amidepsines A, B, C and D, diacylglycerol acyltransferase (DGAT) inhibitors, were determined by spectroscopic studies including various NMR measurements. They were elucidated as 2-hydroxy-4-[[2-hydroxy-4-[(2,4-dimethoxy-6-methylbenzoyl) oxy]6-methylbenzoyl]-oxy]-6-methylbenzoic acid N-alanine amide for amidepsine A, 2-hydroxy-4-[[2-hydroxy-4-[(2-hydroxy-4-methoxy-6-methylbenzoyl) oxy]6-methylbenzoyl]oxy]-6-methylbenzoic acid N-alanine amide for amidepsine B and 2-hydroxy-4-[[2-hydroxy-4-[(2-hydroxy-4-methoxy-6-methylbenzoyl) oxy]6-methylbenzoyl]oxy]-6-methylbenzoic acid N-valine amide for amidepsine C. Amidepsine D was identified with 2,4-di-O-methylgryphoric acid.