Facile Synthesis and Anticancer Activity Study of Novel Series of Substituted and Fused Coumarin Derivatives

Various new substituted and fused coumarin analogues have been synthesized via different synthetic pathways. Among which are variable substituted coumarin derivatives bearing either biologically active side chains or rings at 5, 6, and 3 positions of the coumarin nucleus as indicated in compounds 10 , 12 , 13 , 16–19 , 21 , 23–32 , 38 , and 42–45 . In addition, different pyranocoumarin derivatives either substituted as in compounds 2 , 3 , and 6 or fused as compounds 33–36 , pyranoxanthene analogues such as compounds 4 and 46 , coumarinotriazolothiadiazine derivative 8 , coumarinonaphthodiazocin analogue 39 and coumarinopyrazolone derivative 40 were synthesized. Thirty‐eight of the synthesized compounds were subjected to in vitro anticancer screening against mammalian liver carcinoma HepG2 and breast carcinoma MCF7 cell lines using Cisplatin as a standard reference. The anticancer activity screening results revealed that, among the tested compounds, compounds 16 , 40 , and 43 bearing 4‐chlorophenyl‐2‐aminopyridine‐3‐carbonitrile attached to C₆ position, fused pyrazolone ring or attached to 4‐chlorophenyl‐2‐oxo‐dihydropyridine‐3‐carbonitrile at C₃ position of the coumarin nucleus, respectively, exhibited moderate to strong activity against both cell lines.