Design, synthesis and H1-antihistaminic activity of novel 1-substituted-4-(3-chlorophenyl)-[1,2,4] triazolo [4,3-a] quinazolin-5(4H)-ones

The synthesis, computer prediction of the biological activity and the acute toxicity of 1-Ar-4-R-[1,2,4]triazolo[4,3-a] quinazolin-5(4H)-ones

“…The data of computer prediction of the biological activity obtained are fully consistent with the fact that [1,2,4]triazolo[4,3-a]quinazolin-5(4H)-one derivatives are similar in their chemical structure to the chemical structures described as promising nonsedative H1-antihistaminic drugs [1][2][3][4][5][6][7][8][9][10][11].…”

“…Derivatives of [1,2,4] triazolo [4,3-a]quinazolin-5(4H)-one, which are representatives of the important class of condensed heterocycles possessing a wide range of the biological activity, attract particular interest in this direction. Among their potential pharmacologically significant properties the H1-antihistaminic [1][2][3][4][5][6][7][8][9][10][11], anticonvulsant [12], antibacterial [13][14][15], antitubercular [13,15], antifungal [13,14], anticancer [15], anti-asthmatic [10,16], antiHIV [13], anti-allergic [16], anti-inflammatory [16,17] bioactivities should be mentioned. It determines the prospects for developing synthetic approaches to fundamentally new compounds of the specified class.…”

Synthesis of New Rhodanine, Thiazole, Quinazolin-4-One, Imidazolone and Pyranothiazole Derivatives Incorporating Antipyrine Moiety as Antimicrobial Agents

“…The 1 H NMR spectra of 26 revealed the characteristic methylene proton at δ 4.34 (CH 2 ). Also, the literature indicated that methyl dithiocarbamate group in compound 3 reacts with anthranilic acid or methyl anthrnilate, leading to the formation of quinazoline and its derivatives [19][20][21][22][23]. Thus, interaction of 3 with anthranilic acid in refluxing ethanol in the presence of TEA as catalyst to yield the thiourea intermediate 27 which underwent cyclization via loss of water molecule yielding quinazoline derivative 28, Figure 4 .…”

Synthesis of anti-allergic drugs

“…Veerachamy A. et al proved that quinazolinone derivatives have strong antihistamine activity with alow sedative effect. Manavalan G. et al 77 designed and synthesized a series of 1-substituted-4-(3-chlorophenyl)- [1,2,4]triazolo[4,3-a]quinazolin-5(4H)-ones (Scheme 7) based on the structural modications of quinazolone. In that process, the triazolo group has been substituted with different groups (-H, -CH 3 , -CH 2 CH 3 , -(CH 2 ) 2 CH 3 , -CH 2 Cl) to obtain compounds with improved biological activity.…”