title: Inhibition of α-glucosidase and α-amylase by diaryl derivatives of imidazole-thione and 1,2,4-triazole-thiol.
abstract: The in vivo and in vitro effects of 4,5-diphenylimidazole-2-thione (1), 4,5-diphenyl-1,2,4-triazole-3-thiol (2) and 5-(2-hydroxyphenyl)-4-phenyl-1,2,4-triazole-3-thiol (3) on α-glucosidase and α-amylase were investigated. The in vivo inhibition has been found to be dose-dependent and to occur at a value less than LD50. The in vitro treatment of the enzymes by 4,5-diphenylimidazole-2-thione exhibited a reversible inhibition of the non-competitive type with Ki value of 3.5 and 6.5×10(-5) M for α-glucosidase and α-amylase, respectively. 4,5-diphenyl-1,2,4-triazole-3-thione showed a reversible inhibition of the competitive and non-competitive types, with Ki value of 10(-5) M magnitude, for α-glucosidase and α-amylase. On the other hand, 5-(o-hydroxyphenyl)-4-phenyl-1,2,4-triazole-3-thione did not display an inhibitory effect towards α-amylase but showed a potent inhibition of the competitive type for hepatic α-glucosidase with 10(-5) M magnitude of Ki value.
authors.affiliation: Biochemistry Department, Faculty of Science, Alexandria University, Alexandria, Egypt.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Balba
authors.forename: Neama Abd
authors.initials: NA
authors.lastname: El-Hady
authors.forename: Nabil
authors.initials: N
authors.lastname: Taha
authors.forename: Nadjet
authors.initials: N
authors.lastname: Rezki
authors.forename: El Sayed H
authors.initials: el SH
authors.lastname: El Ashry
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D065089:Glycoside Hydrolase Inhibitors; D007093:Imidazoles / Q000737:chemistry / Q000494:pharmacology; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D008297:Male; D015394:Molecular Structure; D011817:Rabbits; D013329:Structure-Activity Relationship; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000494:pharmacology; D013871:Thiones / Q000737:chemistry / Q000494:pharmacology; D014230:Triazoles / Q000737:chemistry / Q000494:pharmacology; D000516:alpha-Amylases / Q000037:antagonists & inhibitors* / Q000302:isolation & purification / Q000378:metabolism; D000520:alpha-Glucosidases / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors; D007093:Imidazoles; D013438:Sulfhydryl Compounds; D013871:Thiones; D014230:Triazoles; C045575:1,2,4-triazole; C029899:imidazole; D000516:alpha-Amylases; D000520:alpha-Glucosidases