Molecular Hybridization of Naphthoquinones and Thiazoles: A Promising Strategy for Anticancer Drug Discovery

Cancer remains one of the leading causes of morbidity and mortality worldwide, demanding the continuous search for novel and more selective chemotherapeutic agents. Quinones, particularly naphthoquinones, constitute a privileged class of redox-active compounds with well-documented antitumor activity. Likewise, thiazoles represent a heterocyclic scaffold widely explored in medicinal chemistry due to their broad pharmacophoric adaptability and diverse biological activities. In this context, this review comprehensively explores the chemical synthesis and anticancer potential of hybrid molecules combining the naphthoquinone and thiazole scaffolds. The hybridization of these pharmacophores has emerged as a powerful strategy to design multitarget antitumor agents. The review summarizes key synthetic methodologies, including Hantzsch, hetero Diels–Alder cycloaddition and multicomponent reactions, leading to structurally diverse hybrids. Particular emphasis is placed on derivatives exhibiting strong cytotoxic effects against a broad spectrum of cancer cell lines (e.g., OVCAR3, MCF-7, A549, HCT-116, HeLa, and Jurkat), low toxicity toward normal cells and well-defined mechanisms of action involving topoisomerase IIα, EGFR, STAT3, and CDK1 inhibition, as well as ROS generation and cell cycle arrest. Among these, certain hybrids displayed nanomolar potency and high selectivity indices, reinforcing their potential as promising lead compounds for anticancer drug development.