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91.
92.
Successive alkylation of 5-(3-phenylthioureido)-3H-imidazole-4-carboxamides with alkyl halides and chloroacetone gave (N-oxopropylimidazolyl)isothioureas, which were easily converted into derivatives of purine and imidazopyrazinone. In the case of ethyl 5-(3-phenylthioureido)-3H-imidazole-4-carboxylate, primary alkylation occurs at the N atom of the imidazole ring. Reactions of 5-(3-phenylthioureido)-3H-imidazole-4-carboxamides with haloketones afforded a number of 4-hydroxy-2-imidazolyliminothiazolidines and 2-imidazolylimino-Δ4-thiazolines.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2196–2204, October, 2004. 相似文献
93.
Qiang Li Pingfan Wu Yongge Wei Hongyou Guo 《Journal of organometallic chemistry》2006,691(6):1223-1228
An organic-inorganic hybrid compound, (Bu4N)2[Mo6O18(NAr)] (Ar = p-BrC6H4) has been synthesized via the DCC dehydrating protocol of the reaction of [α-Mo8O26]4− with 4-bromoaniline hydrochloride in anhydrous acetonitrile, which has been characterized by UV-Vis spectra, 1H NMR and single crystal X-ray diffraction study. By comparing the UV-Vis spectra, which were used to monitor the reaction, the optimum preparative condition for this compound was also determined. This compound crystallizes in the monoclinic space group P21/n, which is featured in a terminal para-bromophenylimido group linked to an Mo atom of a hexamolybdate cluster by a Mo-N triply bond. In addition, there are π-π dimerization of the neighboring cluster anions though the parallel aromatic rings in their crystals. 相似文献
94.
AbstractFive thienylnicotinamidine derivatives 5a–e were prepared from their corresponding nicotinonitriles 3a–e on treatment with lithium trimethylsilylamide [LiN(TMS)2] followed by hydrolysis using ethanolic/HCl (gas). The nicotinonitriles 3a–e were prepared via Suzuki coupling reaction of bromothienyl derivative 1 with the appropriate phenylboronic acids 2a–e. The DFT calculation was used to optimize the geometric structure of the newly synthesized nicotinamidines. The comparison of DFT/B3LYP calculated spectral data (1H-NMR and 13C-NMR) with the experimental data showed acceptable agreement. Mass fragmentation patterns of 3,4-dimethoxyphenyl, 3,5-dimethoxyphenyl, and 3,4,5-trimethoxyphenyl thienylnicotinamidine derivatives were investigated. 相似文献
95.
96.
Werner?Seebacher Reto?Brun Robert?Saf Robert?WeisEmail author 《Monatshefte für Chemie / Chemical Monthly》2003,134(10):1411-1420
Summary. 4-Aminobicyclo[2.2.2]octanones were converted to their N-oxides and to 4-aminobicyclo[2.2.2]octanes. Furthermore, the 6,7-bis-(4-methoxyphenyl) analogues were synthesized. All products were screened for their activities against Trypanosoma b. rhodesiense and Plasmodium falciparum. The pharmacological results were compared with those of formerly tested bicyclo[2.2.2]octanones and bicyclo[2.2.2]octanols. Structure-activity relationships are discussed.Received April 8, 2003; accepted April 14, 2003
Published online September 25, 2003 相似文献
97.
Robert Weis Reto Brun Robert Saf Werner Seebacher 《Monatshefte für Chemie / Chemical Monthly》2003,134(7):1019-1026
Summary. 4-Aminobicyclo[2.2.2]octanones which were prepared in one-pot-reactions from benzylidene acetone and dialkylammonium rhodanides
were reduced stereoselectively to their corresponding alcohols. The activities of the bicyclic compounds against causative
organisms of tropical deseases were examined. The 4-aminobicyclo[2.2.2]octan-2-ols were in general more active against Trypanosoma b. rhodesiense and Plasmodium falciparum than the corresponding keto compounds.
Corresponding author. E-mail: robert.weis@uni-graz.at
Received November 27, 2002; accepted December 2, 2002
Published online May 2, 2003 相似文献
98.
Jia-you Shu Mo Zhu Yi Shu Qi-jun Liu Tong Li 《高分子科学》2006,(4):395-401
The new chelate resins, abbreviated as PNBMZs and PBBMZs based on epoxide polymer, were synthesized by polycondensation of N,N-diglycidyl-4-glycidyloxyaniline or 1,4-bis(2,3-epoxypropyl)benzene with the primary amine group of 1,3-bis(benzimidazol-2yl)propylamine (BBPAH). The ion exchangers contain 2.71-3.23 mmol of the ligand contents per gram of the resin. Batch extraction capacities were determined for the metal chloride salts in buffer solutions in the pH range from -1 to 6.0. The chelate resins were very selective for Cu^2+, Zn^2+, Cd^2+ in the presence of other divalent transition metal ions. The maximum uptake capacities of PNBMZ (synthetic molar ratio = 1:1.5) under non-competitive condition were found to be 0.94 mmol/g for Cu^2+ at pH = 2, 1.3 mmol/g for Cd^2+ at pH = 1 and 1.75 mmol/g for Zn^2+ at pH = -1 respectively. While in the case of PBBMZ, it was 1.39 mmol/g for Cd〉 at pH = 1. The metal-uptake behaviors for both of them showed strong pH dependence, and their extraction capacities increase with decreasing pH. The uptake of Cu^2+ by the resin PNBMZs at pH = 1 was found to be rather fast with t1/2 = 18 min. Metal-uptake experiments under competitive conditions also confirm that the chelate resins have a high selectivity for Cu^2+, Zn^2+, Cd^2+ and the contrary pH dependence. 相似文献
99.
The reaction of cis-[ClP(μ-NtBu)]2 with N,N′-dimethylurea leads to the formation of both mono- and di-substituted derivatives [ClP(μ-NtBu)2P(NMeCON(H)Me)] and [(μ-NtBu)P(NMeCON(H)Me)]2, instead of monomeric, dimeric or higher oligomeric macrocycles. The structure of [ClP(μ-NtBu)2P(NMeCON(H)Me)] shows rare non-bonded P?Cl and intermolecular hydrogen bonding interactions leading to a 2D-sheet like structure. 相似文献
100.
A novel and green approach for efficient and rapid synthesis of polyhydroquinoline derivatives via unsymmetric Hantzsch reaction using organocatalysts at room temperature was reported. The process is a simple, environmentally friendly, rapid, and high yielding reaction for the synthesis of polyhydroquinoline derivatives. The catalytic efficiency of various small organocatalysts such as l-proline, trans-4-hydroxy-l-proline, l-thiaproline, dl-phenylglycine, and (−)-cinchonidine was studied under aqueous, organic, and solvent free conditions. 相似文献