Synthesis, characterisation and antimicrobial-activity of 3-thio-1,5-dihydro-2,4,3-benzodioxaphosphepin-3-amino acid esters

A new series of 3-thio-1,5-dihydro-2,4,3-benzodioxaphosphepin-3-amino acid esters (4a-k) were synthesized by treating different amino acid ester hydrochlorides (3a-k) with phosphorus monochloride intermediate (2) which was previously formed in situ from 1,2-phenylenedimethanol (1) and thiophosphoryl chloride in the presence of triethylamine in dry tetrahydrofuran (THF) at 0-5 ºC to room temperature. The structures of the title compounds (4a-k) were established by analytical, IR, NMR (1H, 13C and 31P) and mass spectra, and they have been screened for their antimicrobial activity. They exhibited significant antibacterial, and antifungal activity.