A binaphthoquinone from Diospyros greeniwayi

Lupeol, diosindigo A, 7-methyljuglone and a novel binaphthoquinone, 5,5'-di hydroxy-2,7'-dimethyl-3,8'-binaphthalene-1,1',4,4'-tetrone which we have na med as habibone, were isolated from the root bark of Diospyros greeniwayi. This is the second example of a. dimer derived from plumbagin and 7-methylj uglone. Its structure has been elucidated on the basis of its-spectral data mainly,H-1 and C-13 NMR. Diosindigo A and 7-methyljuglone were also detect ed in the stem bark of the plant. (C) 1998 Elsevier Science Ltd. All rights reserved.