Spectroscopic Studies and In Vitro Antitumor Evaluation of Some New Hybrid Ethyl 2-Oxoquinoline-3-carboxylates and Their Halo Derivatives

A series of new ethyl 7-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylates and their halogenated derivatives were synthesized. Ethyl 7-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylate (2) was obtained by the condensation of 2-amino-4-hydroxybenzaldehyde and diethyl malonate. Halogenation of compound 2 with bromine led to the formation of 6,8-dibromo derivative 5, and the acylation and alkylation of 2 and 5 with acetic anhydride and p-chlorophenacyl bromide gave the corresponding acetoxy derivatives 3 and 6 and alkoxy derivatives 4 and 7. Compounds 2–7 were evaluated for their in vitro antiproliferative activity against MCF-7 and HepG2 cancer cell lines. The cell cycle analysis of compound 4 demonstrated cell cycle arrest at the G2/M phase and pre-G1 apoptosis.