细胞毒活性二萜Wangzaozin A的晶体结构

采用单晶X射线衍射技术对对映-贝壳杉烷化合物WangzaozinA的晶体结构进行了研究.研究结果表明,在最小不对称单元中存在两个构象稍有差异(键长和键角不同)的分子,其中两者的3个六元环均为椅式构象,而五元环为扭曲信封式构象.WangzaozinA晶体结构属正交晶系,P2₁2₁2₁空间群,晶胞参数a=0.66485(8)nm,b=2.5796(4)nm,c=1.0473(2)nm,Z=4.分子通过分子内氢键O₃-H₃0…O₂和O₃'-H₃0'…O₂'以及分子间氢键O1-H10…O₃,O1'-H10'…O₃',O₂-H₂0…O₄'和O₂'-H₂0'…O₄形成网络结构,并在晶体中沿c轴排列.体外抗肿瘤实验证实,标题化合物具有显著的细胞毒活性,由SRB法测试其抗Bel-7402及HO^-8910细胞株的IC₅₀值分别为(5.32±0.79)和(4.10±1.00)μmol/L.

Crystal Structure for Cytotoxic Diterpenoids Wangzaozin A

The crystal structure of Wangzaozin A was elucidated on the basis of the single-crystal X-ray diffraction analysis. The {X-ray} crystal structure revealed that there were two molecules with a little difference in the bond lengths and bond angles data in least asymmetry unit, and three six-membered rings were in a chair-like conformation, five-membered rings adopted a twist envelope-like conformation in the compound, respectively. The crystal of the compound was in orthorhombic crystal system, space group P2-12-12-1 with accurate lattice constants as follows a=0.664 85(8) nm, b={2.579 6(4) nm}, c={1.047 3(2) nm}, Z=4. The molecules formed extensive networks through the intra-molecular hydrogen bonds O3-H30…O2, O3'-H30'…O2' and intermolecular hydrogen bonds O1-H10…O3, {O1'-H10'…O3'}, O2-H20…O4', O2'-H20'…O4, and arranged along c axis in the crystal. The compound was found to exhibit a significant cytotoxicity against human tumor Bel-7402 and {HO-8910} cells with (5.32±0.79) and (4.10±1.00) μmol/L in SRB assay, respectively.