4-hydroxy-5-methylcoumarin derivatives from Diospyros kaki Thunb and D-kaki var Sylvestris makino: Structure and synthesis of 11-methylgerberinol

Abstract

Two 4-hydroxy-5-methylcoumarin derivatives have been isolated from the roots of Diospyros kaki Thunb and D. kaki Thunb var. sylvestris Makino. One was shown to be identical to gerberinol, previously isolated from the Compositae plant Gerbera lanuginosa. The other was found to be a new natural product whose structure, 11-methylgerberinol, was proved by spectral analysis and further confirmed by synthesis.