Synthesis and Analgesic Activity of Some New Pyrazoles and Triazoles Bearing a 6,8-Dibromo-2-methylquinazoline Moiety

Molecules

Hosam A. Saad¹  Nermen A. Osman¹ 

[1] ¹Department of Chemistry, Faculty of Science, Taif University, Taif 21974, Saudi Arabia ²Department of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, Zagazig University, Zagazig 44511, Egypt ³Department of Chemistry, Faculty of Science, Zagazig University, Zagazig 44511, Egypt

关键词: isoindol-5-one;    pyrazole;    quinazolin-4(3H)-one;    thiazole;    1;    2;    4-triazole;    1;    3;    4-thiadiazole;    analgesic activity;   

DOI  :  10.3390/molecules161210187

来源: mdpi

【 摘 要 】

2-(6,8-Dibromo-2-methylquinazolin-4-yloxy)-acetohydrazide (4) was prepared by the reaction of 6,8-dibromo-2-methylbenzo-[d][1,3]oxazin-4-one with formamide to afford quinazolinone 2, followed by alkylation with ethyl chloroacetate to give the ester 3. Treatment of ester 3 with hydrazine hydrate and benzaldehyde afforded 4 and styryl quinazoline 5. The hydrazide was reacted with triethyl orthoformate, acetylacetone and ethyl acetoacetate and benzaldehyde derivatives to afford the corresponding pyrazoles 6, 7, 9 and hydrazone derivatives 10a-c. Cyclization of hydrazones 10a-c with thioglycolic acid afforded the thiazole derivatives 11a-c. Reaction of the hydrazide with isothiocyanate derivatives afforded hydrazinecarbothioamide derivatives 12a-c, which cyclized to triazole-3-thiols and thiadiazoles 13a-c and 14a-c, respectively. Fusion of the hydrazide with phthalimide afforded the annelated compound 1,2,4-triazolo[3,4-a]isoindol-5-one (15). The newly synthesized compounds were characterized by their spectral (IR, ¹H-, ¹³C-NMR) data. Selected compounds were screened for analgesic activity.

【 授权许可】

CC BY   
This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.