1-(2,3,4-三羟基苯亚甲基)-4-羟基氨基脲结构与性能的DFT研究

采用DFT方法在B3LYP／6-3lG水平上,对1-(2,3,4-三羟基苯亚甲基)-4-羟基氨基脲(THBMHNU)的电子结构进行了量子化学计算,给出了分子的几何构型和原子的净电荷值、键级和前沿分子轨道特征(组成、能级与轨道电子密度)等参数．初步探讨了分子的电子结构与抗癌活性间的关系,结果表明该分子整体呈非平面构型,仅具C1对称性;分子中除有-NHCONHOH药效团外,尚可能有一附加药效团-三羟基苯亚甲基;分子中的所有O原子及C2、C5原子等都很可能是与酶RR发生作用时的活性位点．

Ab Initio DFT on the Structure-Antitumor Activity Relationship of 1-(2,3,4-Trihydroxy-Henzylidene)-4-Hydroxysemi-Carbazide

Ab initio DFT/B3LYP calculations at 6-31G basis set level were carried out for 1-(2,3,4-trihydroxy-benzylidene)-4-hydroxysemi-carbazide (THBMHNU) and the parameters of the geometry and electronic structure, such as conformation, atomic net charges, bond orders, constituents of frontier molecular orbitals and their eigenvalues, atomic frontier electron densities etc., were obtained. The stmcture-antitumor activity relationship was simply discussed. It was found that the stabilized conformation of THBMHNU is not a "plane-like" shape, only with C1 symmetry, and in addition to the common pharmacophore -NHCONHOH], there is another possible one in THBMHNU, that is, 2,3,4-trihydroxy-benzylidene. The atoms, such as the all of oxygen and nitrogen atoms in the molecular as well as 2,5-position carbon atom etc., are possible reacting activity-sites between THBMHNU and RR.