海风藤中有PAF拮抗活性的苯骈呋喃类新木脂素

自福建产中药海风藤(Piper kadsura (Choisy)Ohwi)的藤茎中又分得5个苯骈呋喃类新木脂素,经光谱分析(UV,IR,MS,NMR,CD)和衍生物制备,确定化合物Ⅱ和Ⅴ为新结构。Ⅱ为化合物denudatin B的对映体,命名为(-)-denudatin B,V为7S,8S-3,4,3′-三甲氧基-7′-氧-缺8′,9′-7.O.4,′8.5′-新木脂素,命名为风藤素M(kadsurenin M)。化合物Ⅰ,Ⅲ和Ⅳ分别为已知化合物海风藤酮(Ⅰ),(-)-acuminatin(Ⅲ)和(+)-licarin A(Ⅳ)。PAF受体结合实验证明,(-)-denudatin B也具有较强的PAF拮抗活性。

PAF ANTAGONISTIC BENZOFURAN NEOLIGNANS FROM PIPER KADSURA

In a continuing search for PAF antagonists, five benzofuran neolignans have been isolated from the aerial part of Piper kadsura (Choisy) Ohwi, a Chinese traditional drug used for the treatment of inflammation and rheumatic conditions. The structure determination was based upon spec-troscopic analysis. Two of the neolignans were found to have new structures and were named as (—)-denudatin B(the enantiomer of denudatin B, Ⅱ) and kadsurenin M (78, 8S-3,4,3'-trimethoxy-7'-oxo-nor-8',9'-7. O. 4',8,5'-neolignan, V). The known compounds kadsurenone (Ⅰ), (—)-acuminatin(Ⅲ) and (+)-licarin A(Ⅳ) were also obtained from the same source. (—)-Denudatin B (Ⅱ) showed potent PAF antagonistic activity in ³H-PAF receptor binding assay.