Synthesis and Biological Evaluation of Chromen-2-One and Chromen-2-Imine Derivatives Bearing Aryldiazenyl Moiety as Expected Antimicrobial Agents

In an attempt to develop new antifungal and antibacterial agents; new series of chromen-2-one and chromen-2-imine derivatives bearing an aryldiazenyl group were synthesized. 2-Chromenones were synthesized through ring closure of 5-aryldiazenylsalicylaldehyde derivatives by ethyl acetoacetate, diethylmalonate and hippuric acid. 2-Chromenimines were synthesized through ring closure of 5-aryldiazenylsalicylaldehydes by malononitrile, cyanoacetamide and cyanoacetamide derivatives. The Knoevenagel reaction between 5-(aryldiazenyl)salicylaldehydes and ethyl cyanoacetate produced coumarin or iminocoumarin depends on the nature of the aromatic ring substituent. The antimicrobial activity for the synthesized chromen-2-one and chromen-2-imine derivatives were evaluated.