Synthesis Of New P-substituted Iminophosphoranes Via Staudinger Raction And Antimicrobial Activity Evaluation

A class of two series of new P-substituted iminophosphoranes, N-(1,3-benzothiazol-2-ylmethyl)-N-(alkyl subtituted-λ⁵-phosphanylidene)amine 5(a-e) and N-(alkyl substituted-λ⁵-phosphanylidene)-(3,5-difluorophenyl)methanamine 9(a-e) was accomplished via Staudinger reaction of sodium azide, 2-chloromethyl benzothiazole (1) or 3,5-difluorobenzylbromide (6) and various trivalent alkyl/aryl phosphines/ethyldiphenylphosphinite/dimethylphenylphosphonite 4(a-e). The structures of new products were elucidated from spectroscopic data and elemental analysis. In vitro antibacterial and antifungal activities of the title compounds were investigated against four bacterial strains and three fungal strains at 50 and 100 μg/mL concentrations, respectively. The minimum inhibitory concentration (MIC) of the title compounds were also determined. Among all the compounds, 3,5-difluorobenzyl core derivatives 9a and 9b, and 1,3-benzothiazol-2-ylmethyl constituent containing compounds, 5b and 5c showed promising antibacterial and antifungal activities, respectively, at lower MIC values in the range of 6.25–25.0 μg/mL and approximately closer to the standards.