A Review on the Synthesis and Anti-cancer Activity of 2-substituted Quinolines

Quinolines substituted at C-2 on the quinoline scaffold have shown interesting anticancer activity in a number of anticancer assays such as breast (MCF-7, MDA-MB 231), human cervical epithelioid (HeLa), oral squamous cell carcinoma (SAS), human stomach adenocarcinoma (AGS, MKN45), hepatocellular (SKHep, HepG-2, Hep-3B), prostate (PC-3, DU145), lung (A549, H-460), gastric (HGC, MNK-74), leukemia (K562, U937, REH, NALM6, CEM/ADR 5000), colon (Colo-205, HCT 116, SW620, Caco-2, HT29), neuroblastoma (IMR32), CNS (SF-268), oesophageal (EAC) and melanoma (A-375). They have been synthesised by a number of strategies starting with isatin, anilines, nitrobenzenes and benzamides and some even with cyclohexanone and cyclohexa-1,3-diones with ammonium acetate. Many of the synthetic strategies employ the derivatisation of quinoline precursors itself. We review here the synthesis of 145 bioactive anticancer quinolines substituted at the 2-position and their anticancer activity.