title: Quinoxalin-2-carboxamides: synthesis and pharmacological evaluation as serotonin type-3 (5-HT3) receptor antagonists.
abstract: A series of quinoxalin-2-carboxamides were designed as per the pharmacophoric requirements of 5-HT(3) receptor antagonists and synthesized by condensing the carboxylic group of quinoxalin-2-carboxylic acid with various amines in the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 1-hydroxybenzotriazole. The structures of the synthesized compounds were confirmed by physical and spectroscopic data. The carboxamides were evaluated for their 5-HT(3) receptor antagonisms in longitudinal muscle-myenteric plexus preparation from guinea pig ileum against 5-HT(3) agonist, 2-methy-5-HT. All the synthesized compounds showed 5-HT(3) receptor antagonism, (4-benzylpiperazin-1-yl)(quinoxalin-2-yl)methanone was the most potent compound among this series.
authors.affiliation: Associate Professor and Group Leader, Pharmacy Group, FD-III, Birla Institute of Technology & Science, Pilani, Rajasthan, India.
authors.forename: Radhakrishnan
authors.initials: R
authors.lastname: Mahesh
authors.forename: Thangaraj
authors.initials: T
authors.lastname: Devadoss
authors.forename: Dilip Kumar
authors.initials: DK
authors.lastname: Pandey
authors.forename: Shushil Kumar
authors.initials: SK
authors.lastname: Yadav
mesh_terms: D000818:Animals; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects* / Q000378:metabolism; D015394:Molecular Structure; D009197:Myenteric Plexus / Q000187:drug effects* / Q000378:metabolism; D017294:Ondansetron / Q000737:chemistry / Q000494:pharmacology; D011810:Quinoxalines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D058831:Serotonin 5-HT3 Receptor Antagonists / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D011810:Quinoxalines; D058831:Serotonin 5-HT3 Receptor Antagonists; D017294:Ondansetron; C042218:quinoxaline-2-carboxylic acid