Arputharaj David Stephen, Rajasekaran Meenashi, Jelsch Christian, Kandasamy Saravanan, Al-Sehemi Abdullah G
Department of Physics, PSG College of Arts and Science, Coimbatore, 641014, Tamil Nadu, India.
Department of Physics, Kandaswami Kandar's College, Velur, 638182, India.
Heliyon. 2022 Jun 2;8(6):e09608. doi: 10.1016/j.heliyon.2022.e09608. eCollection 2022 Jun.
Possible polymorphic forms of the chemotherapy drug, temozolomide were predicted from the and DFT methods. The lattice minimization via distributed multipole analysis was carried out for the hypothetical generated structures. A crystal with unit cell parameters close to the real one and of same space group was retrieved, with partly similar packing and interactions. The analysis of inter molecular interaction (through Hirshfeld surface) and electrostatic potential reveals the complementary sites in the molecule. The 26 predicted structures were analyzed with respect to two computed lattice energies and hydrogen-bond propensity. The lattice energy of the real crystal [EXP] packing ranked number 6 compared on the basis of DMACRYS software and number 3 on the basis of the total lattice energy issued from the Crystalexplorer17 software at the B3LYP/6-31G∗∗ level of theory. The molecule has two strong hydrogen bond donors and five strong acceptors. The predicted packings are stabilized by one or two strong N-H…O/N-H…N as well as weak C-H…O/C-H…N and H…π hydrogen bonds. While the real structure with Z' = 1, EXP, forms only one strong H-bond (N-H…O=C), several of the predicted packings form two strong H-bonds. Two predicted crystal packings have unit cell parameters close to the real structure, one of them shares several common intermolecular interactions.
通过 和密度泛函理论（DFT）方法预测了化疗药物替莫唑胺可能的多晶型形式。对假设生成的结构进行了基于分布式多极分析的晶格最小化。检索到一个晶胞参数接近真实晶胞且空间群相同的晶体，其堆积和相互作用部分相似。分子间相互作用分析（通过 Hirshfeld 表面）和静电势揭示了分子中的互补位点。根据两种计算得到的晶格能和氢键倾向对 26 个预测结构进行了分析。在理论水平 B3LYP/6 - 31G∗∗ 下，基于 DMACRYS 软件，真实晶体 [EXP] 堆积的晶格能排名第 6，基于 Crystalexplorer17 软件得到的总晶格能排名第 3。该分子有两个强氢键供体和五个强氢键受体。预测的堆积通过一个或两个强 N - H…O/N - H…N 以及弱 C - H…O/C - H…N 和 H…π 氢键得以稳定。虽然 Z' = 1 的真实结构 [EXP] 仅形成一个强氢键（N - H…O = C），但一些预测的堆积形成了两个强氢键。两个预测的晶体堆积的晶胞参数接近真实结构，其中一个具有一些共同的分子间相互作用。
