The Structures of Cotylenins A, B, C, D and E

Abstract

The structures of cotylenins, leaf growth substances produced by a fungus, have been assigned on the basis of degradative and spectroscopic evidence. They are novel glycosides with a common aglycone, cotylenol: cotylenins A and C have unusual sugar moieties consisting of an 6-O-methyl-α-D-glucosyl derivative with an oxygenated C₅-isoprene unit.