Syntheses,Characterizations and Crystal Structures of (E)-2-Methyl-1,3-diphenylisothiouronium Iodide and 1,3-Dibenzyl-2-methylisothiouronium Iodide

Two thiouronium iodide salts,（E）-2-methyl-1,3-diphenylisothiouronium iodide（1） and 1,3-dibenzyl-2-methylisothiouronium iodide（2）,were synthesized and characterized by single-crystal X-ray diffraction,1H NMR,IR,UV-vis and luminescence spectra.Single-crystal X-ray diffraction reveals that compound 1 crystallizes in monoclinic system,P21/n space group with a = 11.273（2）,b = 10.318（2）,c = 12.962（3） A,β = 99.03（3）°,V = 1489.0（5） A^3 and Z = 4;compound 2 crystallizes in monoclinic system,C2/c space group with a = 11.706（2）,b = 14.119（3）,c = 20.930（4） A,β = 103.84（3）°,V = 3358.8（12） A^3 and Z = 8.The thiouroniums of both compounds are Y-shaped planar structures to form a cross-conjugated system.The averaged bond lengths of C-N and C-S indicate the presence of ＂Y＂ aromaticity.The researches on UV-vis and luminescence spectra of compounds 1 and 2 indicate that they can form inclusion complex with β-CD in the aqueous solution.

双(萘-类硫脲盐)化合物的光化学反应

合成了一种带芳基的硫脲盐类化合物,对其在光照下的光化学和光物理行为进行了较详细的研究.发现该化合物在光照下,能通过光诱导的分子内电子转移,产生离子自由基和自由基,继而有可能经自由基的重合反应形成环状化合物,并引起所含芳基基团处于合适的易于出现很强激基缔合物的位置.为进一步搞清上述反应机制,工作中设计了相应的实验,包括:ESR的测定、加入稳定的氮氧自由基化合物以及加入β CD来阻抑重合反应的进行等,以证明上述的看法.

Design, Synthesis and <i>in Vitro</i>Antibacterial Activity of 2-thiomethyl-benzimidazole Derivatives

A series of novel substituted benzimidazole (7a - n) derivatives were synthesized and characterized by 1H, 13C Nuclear Magnetic Resonance (NMR) spectra and High Resolution Mass Spectrometry (HRMS). The substitution was done in position -1 and -2 by appropriate groups. These compounds are obtained by N-alkylation reaction with thiomethyl-1H-benzimidazole intermediates (5a - g). Design of intermediates (5a - g) was made by condensation reaction between 2-methylbenzimidazole thiourunium salt (3) and functionalized halides (4) in the presence of sodium hydroxide (NaOH). Among the twenty-one compounds synthesized, ten were evaluated for their antimicrobial activity on three bacterial strains namely: Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853. Only E. coli ATTC 25922 was susceptible to the synthesized derivatives 5g, 7f and 7h with a significant antibacterial activity (CMI is between 250 and 500 μg/mL).