Thermosonication-Catalyzed Synthesis of New 3-Esterified Coumarins as Biocompatible Antitumor Candidates

Background: Coumarin chemical moiety and its-based molecules attracted a lot of research attention by chemists of natural products and organic synthesis. This attention works in two directions: synthetic approaches and biological activities. Methods: In this work, salicylaldehyde was condensed via a thermosonication-catalyzed Knoevenagel reaction with malonic acid, giving coumarin-3-carboxylic acid. The latter was esterified through its carboxylic acid with various 2-functionalized phenols under a thermosonication-promoted SOCl2-catalized esterification reaction.The four 3-esterified coumarins (SY1SY4) were characterized by different spectrophotometer analyzers, including FTIR, 1H-NMR, and 13C-NMR. Four cell lines of malignant type and one of normal class were used to specify the antitumor activity and biocompatibility of the synthetic SY1-SY4, respectively, by employing the MTT-probing methodology. Results: The outcomes indicated the accuracy of the proposed molecular structures, and the synthetic compounds have poor, with the exception of SY1, antitumor activity. Also, the antiproliferative effect of the three compounds (SY2-SY4) is roughly similar against malignant and normal cells. On the other hand, the compound SY1 demonstrated good antitumor activity against the malignant cells used but a poor inhibitory effect toward normal cells. Conclusion: The author concluded from these findings that the molecular structure of SY1 can offer a promising template to synthesize more potent and biocompatible antitumor agents with a coumarin chemical nucleus.