Naphthoquinone Derivatives from the Ebenaceae. IV. Naphthoquinone Derivatives from Diospyros kaki THUNB. and D. kaki THUNB. var. sylvestris MAKINO

From the roots of Diospyros kaki 7-methyljuglone (I), isodiospyrin (II), mamegakinone (III), plumbagin (IV), diospyrin (VIII), and a new 7-methyljuglone dimer (IX), named neodiospyrin, were isolated besides lupeol, betulinic acid, and four uncharacterized compounds (VII, X, XI, and XII). The structure of IX was elucidated. Formation of 3-methoxy-(V) and 2-methoxy-7-methyljuglone (VI) from I in the course of extraction with methanol was examined. From the roots and woods of D. kaki var. sylvestris I, II, III, shinanolone (XIII), the binaphthyl-1, 1'-quinone (XIV), and an unknown phenolic (XV) were isolated besides VII, XI, XII, lupeol, betulin, and betulinic acid.