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Updated: Jul 5, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Synthesis, structure elucidation and antibacterial evaluation of new steroidal -5-en-7-thiazoloquinoxaline
Salman Ahmad Khan1, Kishwar Saleem, Zaheer Khan
1Department of Chemistry, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India.
Abstract:
Some heterocyclic systems namely cholest-5-en-7-thiazolo[4,5-b]quinoxaline-2-yl-hydrazone] were synthesized by the reaction of cholest-5-en-7-one-thiosemicarbazone with 2,3-dichloroquinoxaline at 80 degrees C in high yield. The thiosemicarbazone derivatives were obtained by the condensation of the thiosemicarbazide with steroidal ketones. All the compounds have been characterized by means of elemental analyses, IR, 1H NMR and mass spectroscopic data. The in vitro antibacterial activity was evaluated by disk diffusion method and then the minimum inhibitory concentration (MIC) of compounds was determined against the culture of Escherichia coli. The results were compared with the standard drug chloramphenicol. The results showed that compounds 7 and 8 are better antibacterial agents as compared to chloramphenicol.
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