Synthesis and antimicrobial activity of spiroheterocycles

A new class of spiroheterocycles-pyrazolinyl thienofuranones and isoxazolinyl thienofuranones were prepared from benzylidene thienofuranones by 1,3-dipolar cycloaddition of nitrile imines and nitrile oxides. The dipolar reagents were generated from araldehyde phenylhydrazones and araldoximes in the presence of phase transfer catalyst. All the compounds are tested for their antimicrobial activity. Chloro substituted pyrazolinyl and isoxazolinyl thienofuranones displayed prominent antibacterial activity against B. subtilis greater than the standard drug Chloramphenicol and antifungal activity against A. niger greater than Ketoconazole. © 2019 Author(s)