Glycinoeclepins, Natural Hatching Stimuli for the Soybean Cyst Nematode, Heterodera Glycines . II. Structural Elucidation

Abstract

The structures of three new compounds, glycinoeclepins A, B, and C, isolated from the hatch-stimulating extracts of kidney beans for the soybean cyst nematode, have been determined. The structures were resolved by using spectroscopic methods, especially by the difference NOE techniques, and confirmed by the X-ray diffraction analysis. These structures are characterized by (1) migration of two methyl groups in the C and D rings, (2) oxidative cleavage of the B ring with loss of one carbon atom and (3) presence of the 7-oxabicyclo[2.2.1]heptane system in the A ring, compared with those of cycloartanes, and are regarded as pentanor- (GEA) or nortriterpenes (GEB and GEC).