Reham A. Mohamed

Nucleic acid components and their analogs: Design and synthesis of novel cytosine thioglycoside analogs

ABSTRACT The synthesis of a new category of novel cytosine 4-thioglycoside analogs has been first accomplished. The main step of this strategy is the synthesis of sodium pyrimidine-4-thiolate through the condensation of 2-cyano-N-arylacetamides with sodium cyanocarbonimidodithioate, followed by coupling with α-bromo-sugars to afford the corresponding cytosine 4-thioglycoside analogs. The free thioglycosides were also prepared. Subsequent studies on the application of this strategy for the preparation of other potent pyrimidine thioglycosides are reported.

Pyrimidine non-nucleoside analogs: A direct synthesis of a novel class of N-substituted amino and N-sulfonamide derivatives of pyrimidines

ABSTRACT A convenient method for the regioselective synthesis of pyrimidine non-nucleoside analogs was developed. This study reports a novel and efficient method for the synthesis of a new type of N-substituted amino methylsulfanylpyrimidines and the corresponding pyrazolo[3,4-d]pyrimidines. This series of compounds was designed through the reaction of dimethyl N-cyanodithioiminocarbonate with 2-cyano-N′-(thiophen-2-yl-, furan-2-yl- and pyridin-4-ylmethylene)acetohydrazide and N′-(2-cyanoacetyl)arylsulfonohydrazides. The scope and limitation of the method are demonstrated. The antibacterial and antifungal activities of the synthesized compounds were also evaluated.

Crystal structure of (E)-2-amino-4-methyl-sulfanyl-6-oxo-1-{[(thiophen-2-yl)-methyl-idene]-amino}-1,6-di-hydro-pyrimidine-5-carbo-nitrile.

In the title compound 1-thiophen-2-ylmethyleneaminopyrimidine derivative, the pyrimidine and thienyl rings are inclined to one another by 42.72 (5)°. In the crystal, molecules are linked by N–H⋯Nnitrile and N–H⋯O=C hydrogen bonds, forming chains parallel to the b axis.

Crystal structure of N-(2-amino-5-cyano-4-methyl-sulfanyl-6-oxo-1,6-dihydropyrimidin-1-yl)-4-bromo-benzene-sulfonamide di-methyl-formamide monosolvate.

In the title compound compound, the phenyl and pyrimidine rings are inclined to one another at 31.72 (6)°. The residues are associated into ribbons parallel to [110] by three classical hydrogen bonds. Adjacent ribbons are connected by translation parallel to the c axis by a ‘weak’ hydrogen bond to form a layer structure parallel to (1-10), while a further contact connects the residues in the third dimension.

Recent trends in synthesis of five- and six-membered heterocycles using dimethyl N-cyanodithioiminocarbonate

Abstract New approaches to synthesis of five- and six-membered heterocyclic compounds utilizing dimethyl N-cyanodithioiminocarbonate are surveyed. The scope and limitation of the most important approaches are discussed.