Abstract New crystal, (E)-N’-(4-(dimethylamino)benzylidene)-5-methyl-1H-pyrazole-3-carbohydrazide (3) has been synthesized and characterized by FT-IR, NMR, ESI-MS and single crystal X-ray diffraction (XRD). The optimized molecular structures of free base and cationic species of (3) in gas phase and aqueous solution, vibrational frequencies and, corresponding vibrational assignments have been investigated experimentally and theoretically by using the B3LYP/6-31G∗ and B3LYP/6–311++G∗∗ methods. High solvation energy values are observed for both species of (3) in solution while the NBO and AIM studies support the higher stability of the cationic species in solution. The high energy values ΔEσ→σ∗ and ΔEσ→π∗ transitions, due to the planarity of both CH3 groups linked to N atom, could support the high reactivities of its free base and cationic species, as compared with naloxone, cocaine and scopolamine. Complete vibrational assignments of 105 and 108 vibration modes expected for free base and cationic species of (3) together with the corresponding harmonic force constants are here reported. In vitro antidiabetic and antioxidant activities were revealed for (3). The molecular docking studies of the title compound revealed that it may exhibit anti-diabetic activity via inhibition of α-glucosidase PDB: 3A4A enzyme.

中文翻译：

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(E)-N'-(4-(二甲氨基)苯亚甲基)-5-methyl-1H-pyrazole-3-carbohydrazide的合成、X射线结构、振动光谱、DFT、生物学评价和分子对接研究

摘要 合成了新晶体，(E)-N'-(4-(二甲氨基)苯亚甲基)-5-methyl-1H-pyrazole-3-carbohydrazide (3)，并通过FT-IR、NMR、ESI-MS和单晶 X 射线衍射 (XRD)。已经使用 B3LYP/6-31G* 和 B3LYP/6-311+ 在实验和理论上研究了 (3) 在气相和水溶液中的游离碱和阳离子物种的优化分子结构、振动频率和相应的振动分配+G∗∗ 方法。在溶液中观察到 (3) 的两种物质的高溶剂化能值，而 NBO 和 AIM 研究支持溶液中阳离子物质的更高稳定性。由于与 N 原子相连的两个 CH3 基团的平面性，高能量值 ΔEσ→σ∗ 和 ΔEσ→π∗ 跃迁可以支持其游离碱和阳离子物种的高反应性，与纳洛酮、可卡因和东莨菪碱相比。此处报告了 (3) 的游离碱和阳离子物质预期的 105 和 108 种振动模式的完整振动分配以及相应的谐波力常数。(3) 揭示了体外抗糖尿病和抗氧化活性。标题化合物的分子对接研究表明，它可能通过抑制 α-葡萄糖苷酶 PDB：3A4A 酶而表现出抗糖尿病活性。