Molecules 2011, 16(12), 10187-10201; doi:10.3390/molecules161210187
Article

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

1 Department of Chemistry, Faculty of Science, Taif University, Taif 21974, Saudi Arabia 2 Department of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, Zagazig University, Zagazig 44511, Egypt 3 Department of Chemistry, Faculty of Science, Zagazig University, Zagazig 44511, Egypt
* Author to whom correspondence should be addressed.
Received: 10 October 2011; in revised form: 1 December 2011 / Accepted: 2 December 2011 / Published: 7 December 2011
(This article belongs to the Section Organic Synthesis)
PDF Full-text Download PDF Full-Text [245 KB, uploaded 7 December 2011 11:51 CET]
Abstract: 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.
Keywords: isoindol-5-one; pyrazole; quinazolin-4(3H)-one; thiazole; 1,2,4-triazole; 1,3,4-thiadiazole; analgesic activity

Article Statistics

Load and display the download statistics.

Citations to this Article

Cite This Article

MDPI and ACS Style

Saad, H.A.; Osman, N.A.; Moustafa, A.H. Synthesis and Analgesic Activity of Some New Pyrazoles and Triazoles Bearing a 6,8-Dibromo-2-methylquinazoline Moiety. Molecules 2011, 16, 10187-10201.

AMA Style

Saad HA, Osman NA, Moustafa AH. Synthesis and Analgesic Activity of Some New Pyrazoles and Triazoles Bearing a 6,8-Dibromo-2-methylquinazoline Moiety. Molecules. 2011; 16(12):10187-10201.

Chicago/Turabian Style

Saad, Hosam A.; Osman, Nermen A.; Moustafa, Ahmed H. 2011. "Synthesis and Analgesic Activity of Some New Pyrazoles and Triazoles Bearing a 6,8-Dibromo-2-methylquinazoline Moiety." Molecules 16, no. 12: 10187-10201.

Molecules EISSN 1420-3049 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert