Abstract
The reaction of dihydropyrimidine-2(1H)-thione 4, obtained by the condensation of chalcone 3 with thiourea, with chloroacetic acid and 1,2-dibromoethane furnished compounds 5 and 6 and not their respective isomers 8 and 9. The regiochemistry of the cyclized products and their structure was established by elemental analysis, 1H NMR, 13C NMR, IR and mass spectral data. Density functional theory (DFT) calculations have been carried out for compound 5a and its isomer 8a with Jaguar version 6.5112 using B3LYP density functional method and 6–31G** basis set. 1H and 13C NMR spectra of compound 5a and its possible isomer 8a have been calculated and correlated with experimental results. 2-Arylidene derivatives of 5 were obtained by two routes and their structure was established by spectral data. Compounds 4–7 were screened for their antimicrobial activities.
通过将chalcone 3与硫脲缩合得到的dihydropyrimidine-2(1H)-thione 4与氯乙酸和1,2-二溴乙烷反应,生成了化合物5和6,而不是它们的异构体8和9。通过元素分析、1H NMR、13C NMR、IR和质谱数据,确定了环化产物的区域化学性质及其结构。使用密度泛函理论(DFT)计算了化合物5a及其异构体8a,使用B3LYP密度泛函方法和6-31G**基组,Jaguar版本6.5112进行了计算。计算了化合物5a及其可能的异构体8a的1H和13C NMR谱,并与实验结果进行了相关性分析。通过两种途径获得了5的2-芳基衍生物,并通过光谱数据确定了它们的结构。对化合物4-7进行了抗菌活性筛选。