Suzuki-Miyaura Coupling Mediated Synthesis and Spectral Characterization of Novel Chalcones Derived from Substituted Phenothiazines

Abstract

A new series of chalcone-functionalized 10H-phenothiazine derivatives (3a-h and 4a-h) was synthesized and characterized to explore their potential in medicinal chemistry. The compounds 3a-h and 4a-h were synthesized through Suzuki–Miyaura cross-coupling, subsequently acylated with appropriate cinnamic acid derivatives to afford the desired products. Spectral characterization using FTIR, 1H NMR, mass spectrometry and HPLC confirmed the successful synthesis of all the derivatives. FTIR revealed the characteristic C=O and C=C stretches, while 1H NMR indicated trans-olefinic protons (J = 15.6 Hz), confirming the E-configuration of the chalcone moiety. HRMS data aligned with theoretical molecular weights and HPLC showed excellent purity ranging from 94.2% to 99.3%. Notably, electron-withdrawing substituents such as Cl and CF3 influenced melting points and yields, suggesting significant structural impact on physico-chemical properties. These findings not only validate the synthetic strategy but also offer a structurally diverse framework for future bioactivity studies, particularly in anticancer or CNS-related drug development.