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has been cited by the following article:

• TITLE: Nitriles in Heterocyclic Synthesis: Synthesis of Pyrido[3’,2’:4,5]Thieno[2,3-d] Pyrimidines Derivative

  AUTHORS: Abdel Haleem Mostafa Hussein, Essam Abdel Raheem Eshak, Fathi Aly Abu-Shanab

  KEYWORDS: Nitriles, Heterocyclic Synthesis

  JOURNAL NAME: Open Access Library Journal, Vol.2 No.1, January 29, 2015

  ABSTRACT: 6-Amino-3,5-dicyano-4-methylpyridine-2(1H)-thione 1 reacted with a-haloketones to give the Salkylated derivatives 2a-m. Compound 2a-m undergoes cyclization into thieno[2,3-d] pyridine derivatives 3a-m upon treatment with ethanolic sodium ethoxide. Saponification of 3a gave the amino acid 4 which afforded 5 when refluxed in Ac2O. Treatment of 5 with NH4OAc/AcOH gave 6a. Compound 6a also was obtained when 3c was refluxed in Ac2O. Reaction of 3a with formamide gave 7 and with hydrazine hydrate gave 8. The thiourea derivative 9 was obtained by reaction of 3a with benzoyl isothiocyanate. Compound 9 when refluxed in alcoholic KOH gave 10 and with 98% H2SO4 gave 12. Acetylation of 3a with Ac2O gave the acetyl derivative 13 which on treatment with aniline afforded 14. Compound 14 was cyclized with H2SO4 to 15. Finally treatment of compound 5 with aniline in AcOH afforded 6b.