5-丁氨基咪唑啉-2,4-二酮的合成

以脲和草酸二乙酯为原料通过3步反应合成了5-丁氨基咪唑啉-2,4-二酮,其结构经NMR,IR,MS和元素分析表征。     

Efficient one-pot microwave-assisted synthesis of 3-(thien-3-yl)imidazolidine-2,4-dione analogs

A series of twenty optically pure 3-(thien-3-yl)imidazolidine-2,4-dione derivatives have been synthesized in 41-89% yield on treatment of 1H-thieno[3,2-d][1,3]oxazine-2,4-dione with all natural α-amino acids in a quick one-pot microwave-assisted procedure.     

5-对羟基苄基-2,4-噻唑烷二酮的合成

以对甲氧基苯胺为原料,经3步反应合成了胰岛素增敏剂噻唑烷二酮类药物的关键中间体5-(4-羟基苄基)-2,4-噻唑烷二酮,总收率20.4%,其结构经1HNMR确证。     

Synthesis of 5-(thiazol-5-yl)-4,5-dihydroisoxazoles from 3-chloropentane-2,4-dione

Condensation of 3-chloropentane-2,4-dione with thioamides gives 1-(thiazol-5-yl)ethanones and subsequent Wittig olefination, followed by nitrile oxide 1,3-dipolar cycloaddition to the resulting prop-1-en-2-yl moiety, delivers racemic 5-(thiazol-5-yl)-4,5-dihydroisoxazoles. When this thiazole and isoxazoline diheterocyclic scaffold has a carboethoxy substituent at C2 of the thiazole ring, aminolysis provides for effective diversification. A 50-member library of various 5-(thiazol-5-yl)-4,5-dihydroisoxazoles is reported.     

Synthesis and bioactivity of novel 3-(1-hydroxyethylidene)-5-substituted-pyrrolidine-2,4-dione derivatives

Ten novel 5-substituted derivatives of 3-(l-hydroxyethylidene)pyrrolidine-2,4-dione were synthesized.The compounds were confirmed by IR,:H NMR,MS and elemental analysis.The bioassay indicated that these compounds showed noticeable herbicidal activities,and compounds 6f and 6j exhibited excellent inhibitory activities against the stalk of Echinochloa crusgalli,with EC50 values of 94.4 and 72.7 mg/L,respectively.     

5-Arylidene derivatives of 3-β-D-ribofuranosylthiazolidine-2,4-dione

The synthesis of modified nucleosides, viz., 5-arylidene derivatives of 3--D-ribofuranosyl-thiazolidine-2,4-dione, the structures of which were confirmed by data from the IR and PMR spectra, is described. The compounds have weak activity with respect to smallpox vaccine virus.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 923–927, July, 1983.     

Theoretical studies of 1-(4-substituted-5-hydroxymethyl-tetrahydro-furan-2-ylmethyl)-5-methyl-1H-pyrimidine-2,4-dione molecule

The structural and electronic properties of 1-(4-substituted-5-hydroxymethyl-tetrahydro-furan-2-ylmethyl)-5-methyl-1Hpyrimidine-2,4-dione molecules have been investigated theoretically by performing theoretical calculations. The electronic properties and relative energies of the molecules are obtained. It was found that the 1-(5-hydroxymethyl-4-nitro-tetrahydro-furan-2-ylmethyl)-5-methyl-1H-pyrimidine-2,4-dione molecule have approximately the same structural and electronic properties when compared with the AZT molecules.     

5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基吡唑-3-羧酸的合成

对氯苯丙酮经三甲基氯硅烷保护后与草酸单乙酯单酰氯缩合制得4-(4-氯苯基)-3-甲基-2,4-二氧代丁酸乙酯(4);4与2,4-二氯苯肼盐酸盐缩合成腙、再经分子内环合、水解合成了制备利莫那班的关键中间体——5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基吡唑-3-羧酸,总收率30.3%,其结构经1HNMR和MS确证。     

Ligational and molecular modeling of 3-(N-phenylthiocarbamyl)pentan-2,4-dione

Pentan-2,4-dione reacts with phenylisothiocyanate to give 3-(N-phenylthiocarbamyl)pentan-2,4-dione (HPTPD) containing N, O and S donor atoms. HPTPD has been characterized by elemental analysis, i.r., ¹H-n.m.r. and electronic spectral studies and its structure is confirmed by molecular modeling using a molecular mechanics program. Co^II, Ni^II, Cu^II, Zn^II and Pd^II complexes have been prepared and characterized by spectroscopic techniques. The Cu^II complex has also been studied by e.s.r. spectroscopy. Upon formation of these complexes, except for Pd^II, loss of methine hydrogen occurs and HPTPD coordinates to the metal centers as a monoanionic bidentate ligand. Co^II acetate forms two types of complexes according to the ratio of reactants. The first is brown–green having the formula [Co(PTPD)₂] and is characterized as square-planar and the other is blue with [Co(PTPD)(OAc)] formula and has a tetrahedral geometry; their thermal decompositions have been studied by t.g analysis. The other metal(II) complexes have square-planar structures based on magnetic and electronic spectral data.     

Zinc(II) and lead(II) coordination polymers built by 3-(4-carboxyphenylhydrazono)pentane-2,4-dione

Two coordination polymers [Zn(L)₂(4,4′-bipy)₂] _n (4,4′-bipy = 4,4′-bipyridine) (1) and [Pb(η ²-L)(µ₃-η ²-CH₃COO)(H₂O)] _n (2) have been prepared by the reaction of 3-(4-carboxyphenylhydrazono)pentane-2,4-diketone (HL) with zinc(II) or lead(II) in solution. Polymer 1 shows an infinite zigzag chain, in which Zn(II) are linked by 4,4′-bipy bridges with carboxylate of L^? monodentate to Zn(II). In 2, Pb(II) are bridged by tetradentate µ₃-η ²-CH₃COO^? to form a linear 1-D chain, and each Pb(II) is chelated by carboxylate of L^?. Their molecular structures have been characterized by elemental analysis, infrared, and single-crystal X-ray diffraction. Thermal and fluorescent properties of the two complexes have been investigated.