balsalazide balsalazide balsalazide is an anti-inflammatory drug used in the treatment of inflammatory bowel disease. it is sold under the brand names giazo, colazal in the us and colazide in the uk. it is also sold in generic form in the us by several generic manufacturers. balsalazideclinical datatrade namescolazal, giazoahfs/drugs.commonographmedlineplusa699052license data us dailymed: by mouth pregnancycategory au: c routes ofadministrationby mouthatc codea07ec04 (who) legal statuslegal status au: s4 (prescription only) uk: pom (prescription only) us: ℞-only pharmacokinetic databioavailability<1%protein binding≥99%elimination half-life12hridentifiers iupac name (e)-5-(diazenyl)-2-hydroxybenzoic acid cas number80573-04-2 ypubchem cid5362070drugbankdb01014 ychemspider10662422 yuniip80al8j7zpkeggd07488as salt: d02715chebichebi:267413 ychemblchembl1201346 ncomptox dashboard (epa)dtxsid7040653 echa infocard100.117.186 chemical and physical dataformulac17h15n3o6molar mass357.322 g·mol−13d model (jsmol)interactive image smiles o=c(o)c1cc(ccc1o)/n=n/c2ccc(cc2)c(=o)nccc(o)=o inchi inchi=1s/c17h15n3o6/c21-14-6-5-12(9-13(14)17(25)26)20-19-11-3-1-10(2-4-11)16(24)18-8-7-15(22)23/h1-6,9,21h,7-8h2,(h,18,24)(h,22,23)(h,25,26)/b20-19+ ykey:ipokckjonyrrhp-fmqucbeesa-n y ny (what is this?) (verify) it is usually administered as the disodium salt. balsalazide releases mesalazine, also known as 5-aminosalicylic acid, or 5-asa, in the large intestine. its advantage over that drug in the treatment of ulcerative colitis is believed to be the delivery of the active agent past the small intestine to the large intestine, the active site of ulcerative colitis. it is in the category of disease-modifying antirheumatic drugs (dmards) family of medications. it is unclear exactly how it works. synthesis ex 3 is actually for ipsalazide. see ex 4 for balsalazide proper. same protocol but uses β-alanine. balsalazide synthesis: biorex laboratories, gb 2080796 (1986). starting material is 4-aminohippuric acid, obtained by coupling para-aminobenzoic acid and glycine. that product is then treated with nitrous acid to give the diazonium salt. reaction of this species with salicylic acid proceeds at the position para to the phenol to give balsalazide.