In search of new antibacterial and anticancer compounds,the intermediate of 5-methyl-3-ethoxycarbonyl pyrazole was prepared using acetone and diethyl oxalate as the starting materials through the four-step reactions including condensation,diazanyl addition reaction,dehydration,cyclocondensation.A novel 2,5-bis(5-methyl-3-ethoxyformyl-1-pyrazolyl-2,5-dicarbonyl) thiophene was then synthesized by the reaction of 5-methyl-3-ethoxycarbonyl pyrazole with 2,5-bis(formyl chloride) thiophene.The optimal synthetic conditionts for the target product as validated by one-factor experiment was as follows:reaction temperature,70~80 ℃;molar ratio of the reactants,1∶ 2(2,5-bis(formyl chloride) thiophene∶ 5-methyl-3-ethoxycarbonyl pyrazole).A yield of 50.6% was obtained.The chemical structure of the compound was characterized and confirmed by IR,1H NMR,13C NMR.

Four pyrazoles and their new heterocyclic acylamide derivatives, which are 3,5- di- methylpyrazole, 5-methyl-3-phenylpyrazole, 3,5-diphenylpyrazole, 3-ethoxycarbonyl-5-phenyl- pyrazole, 2,5-bis(3,5-dimethylpyrazolyl-1-carbonyl)thiophene(L1), 2,5-bis(5-methyl-3-phenyl- pyrazolyl-1-carbonyl)thiophene(L2), 2,5-bis(3,5-diphenylpyrazolyl-1-carbonyl)thiophene(L3) and 2,5-bis(3-ethoxycarbonyl-5-phenyl-1-carbonyl)thiophene(L4) were synthesized, and their relevant structures were characterized by elemental analysis, MS, IR, 1 HNMR and 13CNMR spectra. Copyright CJI.

Four novel 2,5-bis(3,5-disubstituded-pyrazolyl-1-carbonyl)thiophenes were synthesized by the reaction of 3,5-disubstituded-pyrazole(2a~2d) with 2,5-bis(chloroformyl)thiophene. 2 was prepared from β-diketone and hydrazine hydrate by cyclization. The structures were characterized by 1H NMR,13C NMR,IR,MS and elemental analysis.