细胞毒活性二萜Wangzaozin A的晶体结构

Crystal Structure for Cytotoxic Diterpenoids Wangzaozin A

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.

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 P212121 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 cell swith （5.32±0.79） and （4.10±1.00） μmol/L in SRB assay, respectively.