海风藤中新木脂素类PAF拮抗活性成分的研究

自中药海风藤Piper kadsura (Choisy)Ohwi]的藤茎中又分离得到四个macrophyllin型双环3,2,1]辛烷类新木脂素,经光谱分析及衍生物的制备,确定化合物Ⅰ和Ⅲ为新结构,命名为风藤素K(kadsurenin K)和风藤素L(kadsurenin L),其化学结构分别为7R,8R,3′R,5′R-△^8′-3,5′-二甲氧基-4-羟基-2′,3′,4′,5′-四氢-2′,4′-氧-7.3′,8.5′-新木脂素(Ⅰ)和7R,8R,3′S,4′R,5′R-△^8′-3,4,5′-三甲氧基-4′-乙酰氧基-2′,3′,4′,5′-四氢-2′-氧-7.3′,8.5′-新木脂素(Ⅲ)。化合物Ⅱ和Ⅳ分别为已报道过的风藤素C和风藤素B。化合物Ⅰ～Ⅳ均有明显的PAF受体拮抗活性。

STUDIES ON PAF ANTAGONISTIC BICYCLO(3,2,1) OCTANOID NEOLIGNANS FROM PIPER KADSURA

As a continuation of our previous report dealing with the structures of novel neolignans from Piper kadsura (Choisy)Ohwi, two other new bicyclo (3, 2, 1) octanoid neolignans, named kadsurenin K and kadsurenin L, were isolated. On the basis of spectral analysis and chemical derivatization, their structures were established as 7R, 8R, 3' R, 5' R- A~(8')- 3, .5' - dimethoxy- 4- hydroxy-2' ,3' ,4', 5'-tetrahydro-2', 4'-oxo-7. 3', 8. 5'-neolignan and 7R, 8R, 3' 8, 4' R, 5' R-A~(8')- 3, 4, 5'-trimethoxy-4'-acetoxy-2', 3', 4', 5'-tetrahydro-2'-oxo-7. 3', 8. 5'-neolignan respectively. Kadsurenin B and kadsurenin C were known compounds. In ~3H--PAF receptor binding assay, kadsurenin B, C, K and L demonstrated significant PAF--antagonistic activity.