SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF SOME NEW SUBSTITUTED ΡΥRIDΟ[3',2':4,5]ΤΗΙΕΝΟ[3,2-d]-PYRIMIDINONE DERIVATIVES

^#E-mail: dr_ahmedfayed14@yahoo.com

*Respiratory Department, Applied Organic & Biochemistry Division, College of Medical Rehabilitation Sciences, Taibah University, Al-Madinah Al-Munawara, 3893 Saudi Arabia
**Applied Organic Chemistry Department, National Research Center, Cairo, Dokki, Egypt
***Pharmaceutical Chemistry Department, Drug Exploration & Development Chair (DEDC), College of Pharmacy, King Saud University, Riyadh, 11451 Saudi Arabia
****Department of Microbial Chemistry, National Research Center, Cairo, Egypt

Recevied November 21, 2013; in final form, December 11, 2013

A series of new 3-substituted-7-(2-chloro-6-ethoxypyridin-4-yl)-9-(2,4-dichlorophenyl)-2-methylpyri-do[3',2':4,5]thieno[3,2-d]pyrimidin-4(3H)-one derivatives were synthesized as antimicrobial agents using 7-(2-chloro-6-ethoxypyridin-4-yl)-9-(2,4-dichlorophenyl)-2-methyl-4H-pyrido[3',2':4,5]thieno[3,2-d]-[1,3]oxazin-4-one as a starting compound. Its condensation with substituted aniline derivatives or phenyl hydrazine gave the corresponding N-substituted derivatives. Treatment of the starting compound with hydrazine hydrate afforded the corresponding N-amino derivative, which was reacted with substituted phenylisocyanate and phenylisothiocyanate derivatives to give the corresponding semicarbazides and thiosemicarbazide derivatives. All the newly synthesized compounds were evaluated for their antimicrobial activities in comparison to streptomycin and fusidic acid as positive controls. The structure assignments of the new compounds are based on chemical and spectroscopic evidence.

Keywords: oxazinone, thienopyrimidine, semi- and thiosemicarbazides, antimicrobial agents

Биоорг. химия 2014, 40 (3): 335-340