Efficient synthesis, X-ray diffraction study and antimicrobial activity of some novel thiazolidin-4-ones and perhydro-1,3-thiazin-4-ones

摘要

Condensations of thiosemicarbazones 1 derived from 1-tetralones with chloroacetic acid and 2-bromopropionic acid in the presence of N -methylpyridinium p -toluenesulfonate (an ionic liquid) yield the corresponding 2-substituted 4-thiazolidinones 2. The reactions of 1 with 3-chloropropionic acid afford perhydro-1,3-thiazinan-4-ones 3 in excellent yields. The structures of compounds 2 and 3 were established on the basis of elemental analysis, IR, NMR and mass spectral data. X-Ray crystallographic studies of compound 2a are reported. Compounds 1- 3 were investigated for antimicrobial activities against Bacillus subtilis, Staphylococcus aureus (Gram-positive bacteria) and Pseudomonas aeruginosa, Escherichia coli (Gramnegative bacteria) and the fungi Aspergillus niger, Candida albicans and Aspergillus fumigatus. Thiazolidin-4-ones were found to be more active than perhydrothiazin-4-ones.