Synthesis and biological screening of some novel thiazolyl chromones and pyrazoles

Esterification of acid 2 with 2-hydroxyacetophenones 1 yielded compounds 3 which have been converted to β-diketones 4 by Baker-Venkatraman transformation. A series of 2-substituted chromones 5 have been obtained by acid catalysed intramolecular cyclization of β-diketones. Substituted pyrazoles 6 have been obtained from chromones 5. All the synthesized compounds have been confirmed by the spectroscopic techniques. Chromones and pyrazoles have been evaluated for their antibacterial and antifungal efficacy.