An efficient synthesis of some new chalcone, acetyl pyrazoline and amino pyrimidine bearing 1,3,5- triazine nucleus as potential antimicrobial and antitubercular agent

Abstract

In an attempt to find a new class of antimicrobial and antitubercular agent, a new series of chalcone, acetyl pyrazoline and amino pyrimidine bearing 1,3,5- triazine nucleus were synthesized with appropriate chemical reagent. Chalcones (D1-D5) were synthesized by the classical Claisen-Schmidt condensation of substituted ketone (C) with variously substituted aldehydes via conventional method. Now treatment of chalcones with hydrazine hydrate/glacial acetic acid and guanidine hydrochloride/Alkali afforded the corresponding acetyl pyrazoline (E1-E5) and amino pyrimidine (F1-F5) derivatives respectively. The chemical structures of all newly synthesized compounds were established on the basis of their FTIR, 1H NMR, 13C NMR, LC-MS as well as elemental analysis. All the newly design compounds were assayed for their in vitro antimicrobial activity against selected pathogens by the Broth dilution method and in vitro antitubercular activity against Mycobacterium tuberculosis H37Rv using Lowenstein-Jensen MIC method. Most of the compounds showed appreciable antimicrobial activity against the all tested strains. Among the synthesized compounds D1, D2, D3, E1, E3, E4, F3 and F4 exhibited excellent antimicrobial activity and said to be the most proficient members of the series. Compound D5 and F5 exhibited promising antitubercular activity.

One‐potandtwo‐potmethods for chalcone derived pyrimidines synthesis and applications

“…[216] Another triazine based pyrimidine having 1,4-oxazine (75) has also been prepared from chalcone (73) with guanidine under basic media at 4-6 h reflux to form 49%-65% yield product. [217,218] The trifluoro substituent based pyrimidine (75) was conveniently synthesized using the same two-pot method [219] [215] whereas the substituent of 4-N-(CH 3 ) 2 C 6 H 4 showed excellent antituberculosis activity. [219] Pyrimidine, featuring coumarin moieties (78), has been synthesized from the guanidine hydrochloride reaction with coumarin chalcone (76) in acidic HCl under ethanol reflux to give 40%-68% yield.…”

“…[217,218] The trifluoro substituent based pyrimidine (75) was conveniently synthesized using the same two-pot method [219] [215] whereas the substituent of 4-N-(CH 3 ) 2 C 6 H 4 showed excellent antituberculosis activity. [219] Pyrimidine, featuring coumarin moieties (78), has been synthesized from the guanidine hydrochloride reaction with coumarin chalcone (76) in acidic HCl under ethanol reflux to give 40%-68% yield. [220] Coumarin is an active natural product scaffold with a wide spectrum of biological properties, [221,222] that is, (antimicrobial, anticancer, antituberculosis, and DNA cleavage).…”