This paper constitutes Part IV of ctylenins, leaf growth substances produced by a fungus. IV. The structures of cotylenins A,B,C,D and E.

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.