Constituents of Veltheimia viridifolia; I. Homoisoflavanones of the bulbs.

The new homoisoflavanone R(-)-3-(4-hydroxybenzyl)-5-hydroxy-6, 7,8-trimethoxychroman-4-one (1) was isolated from the petroleum ether and the diethyl ether extracts of the bulbs of Veltheimia viridifolia (Hyacinthaceae) together with the known homoisoflavanone muscomin (2). The structures of the compounds were elucidated by means of 1H-NMR, 2D 1H-1H-COSY, 13C-NMR, HMQC, HMBC, mass, and CD spectra. Pharmacological testings of the new homoisoflavanone are reported.