(-ANGCHIBANGKINE, A NEW-TYPE OF BISBENZYLISOQUINOLINE ALKALOID, AND OTHER DIMERS FROM PACHYGONE DASYCARPA())

Analysis of the alkaloidal fraction of the stem bark extract of Pachyg one dasycarpa (Menispermaceae) resulted in the isolation of 10 known b isbenzylisoquinolines, (+)-tetrandrine, (+)-penduline, (+)-fangchinoli ne, (+)-atherospennoline, (+)-N-methyl-7-O-demethylpeinamine, (+)-daph noline, (+)-isotrilobine (1), (+)-cocsuline (2), (+)-tricordatine (3), (+)-2'-norcocsuline, and the new alkaloid (+)-12-O-methyltricordatine (4). The last bisbenzylisoquinoline alkaloid isolated, (+)-angchibang kine (5), is the first member of this alkaloid class found to possess three diphenyl ether bridges in the 7-6', 8-7', and 11-12' positions. Structure elucidation of these alkaloids and of (+)-O-methylangchibang kine (6) was achieved by analysis of spectral data. Compounds 4-6 show antiplasmodial activity against Plasmodium falciparum.