Anomaly of Pyrano[2,3‐c]pyrazole Synthesis towards Pyrazolyl‐aryl‐methyl‐malononitrile Derivatives and Their Antimicrobial Activity

Our attempt to prepare pyrano[2,3‐c]pyrazole derivatives from 2‐methyl‐5‐propyl‐1,2‐dihydro‐pyrazolone, malononitrile and benzaldehyde rather lead to the formation of pyrazolyl‐aryl‐methyl‐malononitrile derivatives. Fascinating by this opportunity to branch out the synthesis of substituted pyrazolone derivatives using an efficient multicomponent synthetic approach for pyrazolyl‐aryl‐methyl‐malononitrile derivatives. The synthesis was accelerated using guanidine carbonate as a catalyst in the water reaction medium. The rection has blossomed with the green aspects of synthesis such as organocatalyst, water as reaction medium and ambient temperature providing clean product in higher yield. The synthesized derivatives have been screened for anti‐microbial activity. Compounds 4 c and 4 n showed excellent activity. Six compounds were found to be much effective against the Staphylococcus aureus bacterial strain. The molecular docking study of 4 n showed a high binding affinity with the receptor. Collectively, our study provides eco‐friendly synthesis towards pyrazolyl‐aryl‐methyl‐malononitrile derivatives and we evaluated them as a new class of anti‐microbial compounds.