Synthesis and antimicrobial activity of novel 3 substituted 1,5‐dihydro‐2,4,3‐benzodioxaphosphepine 3‐oxides

Novel 3 substituted 1,5‐dihydro‐2,4,3‐benzodioxaphosphepine 3‐oxides ( 5a–h ) were synthesized by reacting 1,2‐benzenedimethanol ( 1 ) with phosphorus tribromide in the presence of triethylamine at 0–30°C and subsequent reaction of the monobromide ( 2 ) with different Grignard reagents ( 3 ) at room temperature. The products ( 4 ) were converted to corresponding oxides 5a–i by oxidation with H₂O₂ at room temperature. The chemical structures of all the products were confirmed by analytical, IR and NMR (¹H, ¹³C, and ³¹P) spectral data. Their antifungal and antibacterial activity is also evaluated. Most of these compounds exhibited moderate antimicrobial activity in the assay. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:572–575, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20154