Constituents of the cultivated mulberry tree.
From the ethyl acetate extract of root bark of the Japanese cultivated mulberry tree (a variety of Morus alba L.), a novel chalcone derivative with a fused dihydrochalcone partial moiety was isolated and named kuwanon I. The structure was shown to be I on the basis of chemical and spectral data. Kuwanon I (I) is the first example which is regarded biogenetically as a Diels-Alder adduct of a prenylchalcone derivative and a dehydroprenylchalcone derivative. NMR variable temperature studies of I suggested that kuwanon I (I) exists as an equilibrium mixture of conformational isomers in solution.
Nomura
T
T
Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Chiba, Japan.
Fukai
T
T
Matsumoto
J
J
Imashimizu
A
A
Terada
S
S
Hama
M
M