One‐Pot Synthesis of 2‐Amino‐6‐(1, 2‐dihydro‐4‐hydroxy‐2‐oxoquinolin‐3‐yl)‐4‐arylpyridine‐3‐carbonitriles Catalysed by NbCl5 and Their In Vitro Antimicrobial Studies. Issue 34 (9th September 2019)