New quinolinic derivatives as melatonergic ligands: Synthesis and pharmacological evaluation

New series of melatonergic ligands issued from two methoxy-quinolinic scaffolds (2-MQ and 3-MQ), were designed and synthesized. Herein we report the synthetic scheme and pharmacological results of the new prepared compounds. Investigation of compound 11a, the strict 2-MQ analogue, revealed the promising potential of this series. Therefore, pharmacomodulation of the acetamide function of 11a has led to compounds with different pharmacological profiles and the emergence of an MT2 selectivity. Besides, sulphonamide 11b showed the most important MT2 selectivity of this series (167 folds) while methyl and ethyl-ureas 11f and 11g represented the most potent melatonergic ligands of this study. [Display omitted] •New quinolines were prepared as melatoninergic ligands.•Synthesized derivatives showed good binding affinities at both MT1 and MT2.•Sulphonamide 11b showed an important MT2 selectivity of about 167.•Methylurea 11f and ethylurea 11g represented the most potent of this series.