Chem. Pharm. Bull., 54(10),1403-1407, October 2006

Regular Articles

Radical-Scavenging Activities of New Megastigmane Glucosides from Macaranga tanarius (L.) MÜLL.-ARG.

Katsuyoshi MATSUNAMI,^a Ichiko TAKAMORI,^a Takakazu SHINZATO,^b Mitsunori ARAMOTO,^c Kazunari KONDO,^d Hideaki OTSUKA,^*,a and Yoshio TAKEDA^e

^a Department of Pharmacognosy, Graduate School of Biomedical Sciences, Hiroshima University; 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan: ^b Subtropical Field Science Center, Faculty of Agriculture, University of the Ryukyus; 1 Senbaru, Nishihara-cho, Nakagami-gun, Okinawa 903-0129, Japan: ^c Iriomote Station, Tropical Biosphere Research Center, University of the Ryukyus; 870 Aza Uehara, Taketomi-cho, Yaeyama-gun, Okinawa 907-1541, Japan: ^d Division of Foods, National Institute of Health Sciences; 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan: and ^e Faculty of Integrated Arts and Sciences, The University of Tokushima; 1-1 Minamijosanjima-cho, Tokushima 770-8502, Japan. * To whom correspondence should be addressed. e-mail: hotsuka@hiroshima-u.ac.jp

Four new megastigmane glucosides, named macarangiosides A-D (2-5), together with mallophenol B, lauroside E, methyl brevifolin carboxylate, and hyperin and isoquercitrin as a mixture were isolated from the leaves of Macaranga tanarius (L.) MÜLL.-ARG. (Euphorbiaceae). Their structures were elucidated by spectroscopic and chemical analyses. Macarangioside A-C (2-4) and mallophenol B were galloylated on glucose moiety and possessed the potent 2,2-diphenyl-picrylhydrazyl (DPPH) radical-scavenging activity.

Key words Macaranga tanarius; Euphorbiaceae; megastigmane glucoside; macarangioside; 2,2-diphenyl-picrylhydrazyl (DPPH)