title: Conjugates of degraded and oxidized hydroxyethyl starch and sulfonylureas: synthesis, characterization, and in vivo antidiabetic activity.
abstract: Orally administered drugs usually face the problem of low water solubility, low permeability, and less retention in bloodstream leading to unsatisfactory pharmacokinetic profile of drugs. Polymer conjugation has attracted increasing interest in the pharmaceutical industry for delivering such low molecular weight (Mw) drugs as well as some complex compounds. In the present work, degraded and oxidized hydroxyethyl starch (HES), a highly biocompatible semisynthetic biopolymer, was used as a drug carrier to overcome the solubility and permeability problems. The HES was coupled with synthesized N-arylsulfonylbenzimidazolones, a class of sulfonylurea derivatives, by creating an amide linkage between the two species. The coupled products were characterized using GPC, FT-IR, (1)H NMR, and (13)C NMR spectroscopy. The experiments established the viability of covalent coupling between the biopolymer and N-arylsulfonylbenzimidazolones. The coupled products were screened for their in vivo antidiabetic potential on male albino rats. The coupling of sulfonylurea derivatives with HES resulted in a marked increase of the hypoglycemic activity of all the compounds. 2,3-Dihydro-3-(4-nitrobenzensulfonyl)-2-oxo-1H-benzimidazole coupled to HES10100 was found most potent with a 67% reduction in blood glucose level of the rats as compared to 41% reduction produced by tolbutamide and 38% by metformin.
authors.affiliation: Department of Chemistry, Quaid-i-Azam University , Islamabad-45320, Pakistan.
authors.forename: Muhammad Azhar
authors.initials: MA
authors.lastname: Abbas
authors.forename: Shahid
authors.initials: S
authors.lastname: Hameed
authors.forename: Muhammad
authors.initials: M
authors.lastname: Farman
authors.forename: Jörg
authors.initials: J
authors.lastname: Kressler
authors.forename: Nasir
authors.initials: N
authors.lastname: Mahmood
mesh_terms: D000577:Amides / Q000737:chemistry; D000818:Animals; D001562:Benzimidazoles / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic; D004337:Drug Carriers / Q000737:chemistry*; D006895:Hydroxyethyl Starch Derivatives / Q000737:chemistry*; D007004:Hypoglycemic Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D008970:Molecular Weight; D010084:Oxidation-Reduction; D010539:Permeability; D051381:Rats; D012995:Solubility; D013453:Sulfonylurea Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D000577:Amides; D001562:Benzimidazoles; D004337:Drug Carriers; D006895:Hydroxyethyl Starch Derivatives; D007004:Hypoglycemic Agents; D013453:Sulfonylurea Compounds; C014353:benzimidazolone