7.

Flavonoids from Twigs of Millettia leptobotrya Dunn.

Zhi Na, Qishi Song and Huabin Hu

Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences , Mengla, Yunnan, 666303 , P. R. China

Laboratory of Tropical Plant Resource Science, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, P. R. China

Abstract: A new furanoisoflavone, 2 ' -methoxy-4 ' ,5 ' -methylenedioxy-[2 '' ,3 '' :7,8 ] furanoisoflavone, leptobotryanone ( 1 ) , and a new natural O-prenylated isoflavone, 4 ' -γ,γ-dimethylallyloxy-5,7-dihydroxyisoflavone ( 2 ) , were isolated from the twig s of Millettia leptobotrya, together with twelve known flavonoids, 4 ' -γ,γ-dimethylallyloxy-5-hydroxy-7-methoxyisoflavone ( 3 ), 2 ' ,6,7-trimethoxy-4 ' ,5 ' -methylenedioxy- isoflavone (4), 2 ' ,7-dimethoxy-4 ' ,5 ' -methylenedioxyisoflavone (5), maximaisoflavone B (6), medicarpin (7) , maackiain (8), genistein (9), biochanin A (10), prunetin (11), chrysoeriol (12) , kaempferol (13) and desmoxyphyllin A (14) The structures of new compounds were elucidated on the basis of spectroscopic data interpretation , including 1D and 2D NMR and HREIMS. Th is is the first phytochemical investigation of this plant.

Keywords: Millettia leptobotrya Dunn ; Leguminosae; leptobotryanone; isoflavone .