This study focuses on advancing green chemistry in anticancer drug discovery, particularly through the synthesis of azine derivatives with a naphthalene core using CS–SO3H as a catalyst. Novel benzaldazine and ketazine derivatives were synthesized using (E)-(naphthalen-1-ylmethylene)hydrazine and various carbonyl compounds. The methods employed included thermal and grinding techniques, utilizing CS–SO3H as an eco-friendly and cost-effective catalyst. The approach resulted in high yields, short reaction times and demonstrated catalyst reusability. Cytotoxicity tests highlighted compounds 3b, 11 and 13 as potent against the HEPG2-1. This study successfully aligns with the objectives of eco-conscious drug development in organic chemistry. Molecular docking and in silico studies further indicate the potential of these ligands as antitumor medicines, with favorable oral bioavailability properties.