桥环黄皮酰胺差向异构体的结构研究

STUDY ON THE STRUCTURE OF EPIMERIDES OF CYCLOCLAUSENAMIDE

目的 研究桥环黄皮酰胺差向异构体的结构。方法 用单晶X 射线衍射分析法测定了从植物黄皮提取物中分离得到的化合物I和采用合成方法得到的化合物III的晶体结构 ,并用分子力学计算方法分别模建化合物II和IV的立体结构。结果 化合物I和III的分子式均为C18H17O2 N ,计算分子量为 2 79 34,其中化合物I属单斜晶系 ,空间群为P2 1;化合物III属三斜晶系 ,空间群为P1。结论 化合物I和III均为桥环黄皮酰胺 ,但在C6位苯环的取向不同。桥环黄皮酰胺可形成 4对差向异构体 。

AIM To study the structures of the epimerides of cycloclausenamide. METHODS The structures of compound I, extracted from Clausena lansium (Lour.) Skeels, and synthesized compound III were determined by single crystal X ray diffraction analysis. The stereo structures of compound II and IV were also built up through Tripos force field based on crystal structures of compound I and III. RESULTS The molecular formula and molecular weight were found to be C 18 H 17 O 2N and 279 34 respectively. Compound I crystallized in monoclinic system, space group P2 1 with a =0 5928(1), b =1 5014(1), c =1 6190(1) nm, V =1 4410(3) nm 3, Z =4, D x=1 288 g·cm -3 , R f=0 075, R w=0 073( w =1/σ 2｜F｜), S =3 983; compound III crystallized in triclinic system, space group P1 with a =0 5667(1), b =1 2934(1), c =2 1119(1) nm, α=102 17(1), β=90 25(1), γ=102 65(2)°, V =1 4770(5) nm 3, Z =4, D x=1 224 g·cm -3 , R f=0 047, R w=0 051( w =1/σ 2｜F｜), S =0 467. CONCLUSION These results showed that compound I and III both are cycloclausenamide except that the directions of the phenyl group on C 6 are different. Cycloclausenamide can form 4 pairs of epimerides but the directions of the phenyl group does not affect their energy in free state.