title: Colon-specific, mutual azo prodrug of 5-aminosalicylic acid with L-tryptophan: synthesis, kinetic studies and evaluation of its mitigating effect in trinitrobenzenesulfonic acid-induced colitis in rats.
abstract: Mutual azo prodrug of 5-aminosalicylic acid with l-tryptophan was synthesized by coupling l-tryptophan with salicylic acid, for targeted drug delivery to the inflamed gut tissue in inflammatory bowel disease. The structure of synthesized prodrug was confirmed by elemental analysis, IR and NMR spectroscopy. In vitro kinetic studies in HCl buffer (pH 1.2) showed negligible release of 5-aminosalicylic acid, whereas in phosphate buffer (pH 7.4) 18% release was observed over a period of 7 h. In rat fecal matter, 87.9% of 5-aminosalicylic acid was released with a half-life of 143.6 min, following first order kinetics. The azo conjugate was evaluated for its ulcerogenic potential by Rainsford's cold stress method. The ameliorating effect of the azo conjugate and therapeutic efficacy of the carrier system was evaluated in trinitrobenzenesulfonic acid-induced experimental colitis model. The synthesized prodrug was found to be equally effective in mitigating the colitis in rats as that of sulfasalazine without the ulcerogenicity of 5-aminosalicylic acid.
authors.affiliation: Department of Pharmaceutical Chemistry, Bharati Vidyapeeth University, Poona College of Pharmacy, Pune 411038, Maharashtra, India. suneeladhaneshwar@rediffmail.com
authors.forename: Suneela S
authors.initials: SS
authors.lastname: Dhaneshwar
authors.forename: Neha
authors.initials: N
authors.lastname: Gairola
authors.forename: Mini
authors.initials: M
authors.lastname: Kandpal
authors.forename: Gaurav
authors.initials: G
authors.lastname: Vadnerkar
authors.forename: Lokesh
authors.initials: L
authors.lastname: Bhatt
mesh_terms: D000818:Animals; D001391:Azo Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000627:therapeutic use*; D001835:Body Weight / Q000187:drug effects; D003092:Colitis / Q000139:chemically induced / Q000188:drug therapy* / Q000473:pathology*; D007700:Kinetics; D019804:Mesalamine / Q000737:chemistry / Q000627:therapeutic use*; D015394:Molecular Structure; D009929:Organ Size / Q000187:drug effects; D011355:Prodrugs / Q000138:chemical synthesis / Q000737:chemistry / Q000627:therapeutic use*; D051381:Rats; D014302:Trinitrobenzenesulfonic Acid / Q000494:pharmacology*; D014364:Tryptophan / Q000627:therapeutic use*
chemical_list: D001391:Azo Compounds; D011355:Prodrugs; D019804:Mesalamine; D014364:Tryptophan; D014302:Trinitrobenzenesulfonic Acid