Ionic liquid-mediated three-component synthesis of fluorinated spiro-thiazine derivatives and their antimycobacterial and DNA cleavage activities

Abstract

A simple, green and catalyst-free novel protocol is developed for the synthesis of medicinally important spiro[indole-3,2′[1,3]-thiazine]-2, 4′-dione and spiro[acenaphthylene-1,2′-[1,3]thiazine]dione libraries by the tandem reaction of readily available reagents in 1-butyl-3- methylimidazolium hexafluorophosphate [bmim][PF6]. The ionic liquid has been used as a solvent as well as catalyst for this reaction. This reaction proceeded smoothly in good to excellent yields and offered several other advantages including short reaction time, simple experimental workup procedure and no by-products. The synthesized compounds were subjected to antimycobacterial efficacy against Mycobacterium tuberculosis H37Rv strain and DNA cleavage activity. [Figure not available: see fulltext.] © 2013 Indian Academy of Sciences.