Synthesis, Characterization and Biological Evaluation of Novel 1- Substituted-4-(2-methoxyphenyl)-s-triazolo[4,3-a]quinazolin-5(4H)-ones
نویسندگان
چکیده
In the present study a series of 1-substituted-4-(2-methoxyphenyl)-s-triazolo[4,3-a]quinazolin-5(4H)-ones were synthesized and are screened for their H1-antihistaminic activity. The synthesized compounds were characterized by IR, H-NMR and mass spectral data; the purity of the compounds was determined by elemental analysis. Antihistaminic activity of the title compounds was evaluated by histamine induced bronchoconstriction method in guinea pigs. Among the series, 4-(2-methoxyphenyl)-1-methyl[1,2,4] triazolo[4,3-a]quinazolin-5(4H)-one (5) was the most potent with the percentage protection of 68.67% and its potency is comparable to that of standard chlorpheniramine maleate (percentage protection 71.00). Interestingly the sedative property of compound 5 was found to be negligible (7.4%) when compared to chlorpheneramine maleate (35.4%).
منابع مشابه
Synthesis and pharmacological investigation of novel 4-(3-ethylphenyl)-1-substituted-4H-[1,2,4]triazolo[4,3-a] quinazolin-5-ones as a new class of H1-antihistaminic agents.
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