Synthesis of new thiophene and selenophene derivatives

In this study, derivatives of thieno[2,3-d]pyrimidine and selenopheno[2,3-d]pyrimidine, thienopyrimidinhydrazono and 2-(benzylideneamino)-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carbonitrile having polyfunctional groups were synthesized. The synthesized compounds are thought to show biological activity.In the first phase of the study, using the method of Gewald; 2-amino-5,7-dihydro-4H-thieno[2,3-c]thiopyran-3-carbonitrile was synthesized from the reaction of malonitrile with tetrahydro-4H-thiopyran-4-on and elemental sulfur, 2-amino-5,7-dihydro-4H-selenopheno[2,3-c]thiopyran-3-carbonitrile was synthesized from the reaction of malonitrile with tetrahydro-4H-thiopyran-4-on and metallic selenium and 2-amino-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carbonitrile was synthesized from the reaction of malonitrile with tetrahydro-4H-pyran-4-on and elemental sulfur. The reaction of synthesized; 2-amino-5,7-dihydro-4H-thieno[2,3-c]thiopyran-3-carbonitrile with formamide gave 6,8-di hydro-5H-thiopyrano[4',3':4,5]thieno[2,3-d]pyrimidin-4-amine and the reaction of synthesized 2-amino-5,7-dihydro-4H-thieno[2,3-c]thiopyran-3-carbonitrile with pyrrolidin-2-one and POCl3 gave 3,4,8,9-trahydro-1H-pyrrolo[1,2-a]thio pyrano[4',3':4,5]thieno[2,3-d]pyrimidin-5(7H)-imine compounds. The reaction of synthesized; 2-amino-5,7-dihydro-4H-thieno[2,3-c]thiopyran-3-carbonitrile and 2-amino-5,7-dihydro-4H-selenopheno[2,3-c]thiopyran-3-carbonitrile with formic acid gave respectively of 5,6-dihydro-3H-thiopyrano[4',3':4,5]thieno[2,3-d]pyrimidin-4(8H)-on and 5,6-dihydro-3H-thiopyrano[4',3':4,5]selenopheno[2,3 -d]pyrimidin-4(8H)-one compounds. 5,6-dihydro-3H-thiopyrano[4',3':4,5] thieno[2,3-d]pyrimidin-4(8H)-on and 5,6-dihydro-3H-thiopyrano[4',3':4,5] selenopheno[2,3-d]pyrimidin-4(8H)-one were then reacted with POCl3 to obtain, respectively of 4-chloro-6,8-dihydro-5H-thiopyrano[4',3':4,5]thieno[2,3-d] pyrimidine and 4-chloro-6,8-dihydro-5H-thiopyrano[4',3':4,5]selenopheno[2,3-d]pyrimidine compounds. 4-chloro-6,8-dihydro-5H-thiopyrano[4',3':4,5]thieno [2,3-d]pyrimidine was then reacted with 4-aminobenzenesulfonamide to obtain 4-((6,8-dihydro-5H-thiopyrano[4',3':4,5]thieno[2,3-d]pyrimidin-4-yl)amino) benzenesulfonamide. Reaction of 4-chloro-6,8-dihydro-5H-thiopyrano[4',3':4,5] thieno[2,3-d]pyrimidine with hydrazine gave 4-hydrazinyl-6,8-dihydro-5H-thiopyrano[4',3':4,5]thieno[2,3-d]pyrimidine.The second phase, as result of the condensation of synthesized 4-hydrazinyl-6,8-dihydro-5H-thiopyrano[4',3':4,5]thieno[2,3-d]pyrimidine with salicylaldehyde and its derivatives gave 4-bromo-2-((2-(6,8-dihydro-5H-thiopyrano[4',3':4,5] thieno[2,3-d]pyrimidin-4-yl)hydrazono)methyl)phenol, 4-chloro-2-((2-(6,8-di hydro-5H-thiopyrano[4',3':4,5]thieno[2,3-d]pyrimidin-4-yl)hydrazono)methyl) phenol, 2-((2-(6,8-dihydro-5H-thiopyrano[4',3':4,5]thieno[2,3-d]pyrimidin-4-yl) hydrazono)methyl)-4-methylphenol, 2-((2-(6,8-dihydro-5H-thiopyrano[4',3':4,5] thieno[2,3-d]pyrimidin-4-yl)hydrazono)methyl)phenol and 3-((2-(6,8-dihydro-5H-thiopyrano[4',3':4,5]thieno[2,3-d]pyrimidin-4-yl)hydrazono)methyl)phenol compounds. Reaction of 4-hydrazinyl-6,8-dihydro-5H-thiopyrano[4',3':4,5] thieno[2,3-d]pyrimidine with 1H-pyrrole-2-carboxyaldehyde gave 4-(2-((1H-pyrrol-2-yl)methylene)hydrazinyl)-6,8-dihydro-5H-thiopyrano[4',3':4,5]thieno [2,3-d]pyrimidine compound.The other part of the study, Reaction of synthesized 2-amino-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carbonitrile with salicylaldehyde and its derivatives gave 2-((2-hydroxybenzylidene)amino)-5,7-dihydro-4H-thieno[2,3-c]pyran-3- carbonitrile, 2-((3-chloro-5-fluoro-2-hydroxybenzylidene)amino)-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carbonitrile, 2-((5-fluoro-2-hydroxy-3-methylbenzyli- dene)amino)-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carbonitrile, 2-((5-chloro-2-hydroxybenzylidene)amino)-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carbonitrile, 2-((5-bromo-2-hydroxybenzylidene)amino)-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carbonitrile ve 2-((2-hydroxy-5-methylbenzylidene)amino)-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carbonitrile compounds. The structures of the synthesized compounds were confirmed by spectroscopic techniques (1H-NMR, 13C-NMR ve FTIR).Key Words : Thiophene, Selenophene, Gewald Method Selenopyrimidine, Thienopyrimidinhyrazono