Structure-activity relationships of quaternary protoberberine alkaloids having an antimalarial activity
作者:Kinuko Iwasa、Yumi Nishiyama、Momoyo Ichimaru、Masataka Moriyasu、Hye-Sook Kim、Yusuke Wataya、Takao Yamori、Turuo Takashi、Dong-Ung Lee
DOI:10.1016/s0223-5234(99)00127-0
日期:1999.12
Seventeen quaternary protoberberine alkaloids related to berberine I were tested for antimalarial activity in vitro against Plasmodium falciparum and structure-activity relationships are proposed. The activity of the protoberberine alkaloids was influenced by the type of the oxygen substituents on rings A, C and D and the position of the oxygen functions on ring D. The position of the oxygen functions on ring D and the type of the oxygen substituents at the C-13 position (ring C) strongly influenced the activity. Shifting the oxygen functions at C-9 and C-10 to C-10 and C-Il on ring D resulted in a significant increase in the activity. Compounds bearing a methylenedioxy function at C-2 and C-3 (ring A) or C-9 and C-IO (ring D) showed higher activity than those which have methoxy groups at the same positions. Introduction of a methoxy group into the C-l position (ring A) decreased the activity. Replacement of a hydroxy group at C-2 or C-3 (ring A) by a methoxy group led to a reduction in the activity. Displacement of a hydroxy function at C-13 (ring C) by the oxygen substituents such as OMe, Oft, OCOOEt, and OCON(Me)(2) reduced the activity. In the same replacement at C-9 (ring D), the activity depended upon the type of the oxygen function. Six protoberberines displayed more potent activity than berberine 1. The activity decreased in the order: 10, 11, 17 and 18 > 7 and 8 > 1. (C) 1999 Editions scientifiques et medicales Elsevier SAS.