Dimerization of Sodium Enolates of Malonic Ester and Acetylacetone Effected by the Action of 4-Methyl-3,4-dibromotetrahydropyran

Russian Journal of Organic Chemistry -     

Solid-Phase Synthesis of a Monofunctional trans-a(2)Pt(II) Complex Tethered to a Single-Stranded Oligonucleotide

Cross-linking ability is possible with the oligonucleotide-tethered, monofunctional trans-Pt(II) complex shown. It was synthesized by a novel solid-phase approach comprising conjugation of immobilized tetrathymidylic acid with a trans-a(2)Pt(II) building unit, ammonolysis, and transformation of the resulting complex (R=1-N-cyclohexylmethylthyminate) into the chloro derivative (R=Cl). a=NH(2)CH(3), T=thymine.     

Synthesis and Antioxidant Activity of N -Aminomethyl Derivatives of Ethosuximide and Pufemide Anticonvulsants

Aminomethylation of 3-methyl-3-ethylpyrrolidin-2,5-dione (ethosuximide) and 3-(4-isopropoxyphenyl)pyrrolidine-2,5-dione (pufemide) with a 25% aqueous formalin solution and alkyl(aryl)amines yielded corresponding N-aminomethyl derivatives. The antioxidant activity of the synthesized compounds and their effect on some parameters of the blood coagulation system were studied.     

内蒙古地区天然植物沙棘果中黄色素的提取工艺及性质研究

以内蒙古地区沙棘果实为原料，研究了提取黄色素的工艺条件，同时对该色素的性质进行了初步探讨。结果表明，以95％的乙醇溶液作浸提剂，提取的黄色素浓度最高，工艺流程简单易行，且无毒，无污染。对提取的黄色素进行的性质试验表明，沙棘黄色素对光、热具有较好的稳定性，适用于酸性或弱碱性的食品中，葡萄糖、氧化剂(H2O2)、还原剂(Na2SO3)等食品添加剂均无明显影响以上结果为这种优良天然色素的开发与应用提供了参考。     

Phase-transfer catalyzed alkylation of pyrazoles and 1,2,4-triazole with cis- and trans-1,4-dichloro-2-butenes

The phase-transfer catalyzed (PTC) alkylation of pyrazoles and 1,2,4-triazole with cis- and trans-1,4-dichloro-2-butenes (DCB) has been examined. The monoalkylation products of pyrazoles with cis-DCB are bicyclic salts formed by intramolecular cyclization of the intermediate cis-1-(4-chloro-2-butenyl)pyrazoles. The corresponding trans-compounds are incapable of cyclization, but on prolonged standing they undergo intermolecular polyquaternization. Both cis- and trans-DCB undergo phase-transfer catalyzed reaction with 1,2,4-triazole to give polymeric quaternary salts. Conditions have been worked out for the dehydrochlorination of 1-(4-chloro-2-butenyl)azoles to 1-(butadien-2-yl)azoles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 497–503, April, 1989.     

Dielectric permittivity and temperature effects on spin-spin couplings studied on acetonitrile

Dielectric permittivity (epsilon) and temperature effects on indirect spin-spin coupling constants were studied using acetonitrile as a probe molecule. Experiments were accompanied by hybrid DFT (density functional theory) studies, where the solvent was modeled using the polarization continuum model. Owing to its numerous types of J-couplings, acetonitrile is a very convenient molecule against which various basis sets can be tested or the best basis set can be selected for a given study. The results show reasonable agreement between calculated and experimental values. According to our data, scalar spin-spin coupling constants undergo substantial shifts at lower values of the dielectric constant. Thus J-coupling values are not transferable between measurements made at differing epsilon-conditions, and the assumption of the epsilon-independence of the J-coupling can lead to crucial mistakes in experiments using low-epsilon media. Dielectric permittivity also causes small geometric fluctuations within the molecule, which themselves can affect J-coupling values. Examinations of the results computed with frozen and relaxed geometries show that geometry mediation mostly affects the spin-dipole term of the J-coupling; hence, for accurate evaluation of the latter, frozen geometries are not acceptable. Another interesting fact revealed is the connection between the solvent dielectric properties and the temperature-dependence slopes of J-couplings in corresponding media.     

Synthesis of 1-(4-butoxyphenyl)-1-cyclohexyl-3-(4-arylpiperazin-1-yl)-2-phenylpropan-1-ols and their dihydrochlorides

Aminomethylation of 1-(4-butoxyphenyl)-2-phenylethanone with paraformaldehyde and substituted piperazines in ethanol medium results in 1-(4-butoxyphenyl)-3-(4-R-piperazin-1-yl)-2-phenylpropan-1-ones. The latter react with cyclohexylmagnesium halide to give 1-(4-butoxyphenyl)-1-cyclohexyl-3-(4-arylpiperazin-1-yl)-2-phenylpropan-1-ols. Reduction of the prepared β-aminoketones with lithium aluminum hydride in absolute diethyl ether leads to the secondary aminopropanols. The prepared compounds could be converted into the corresponding dihydrochlorides.     

种植沙生植物--沙棘改善内蒙古地区生态环境

结合内蒙古地区现状，对沙棘的生物学和生态学特性、沙棘属植物化学成分和微量元素及种植沙生植物——沙棘的重要性和必要性进行了详细的研究和探讨。研究表明，沙棘属植物具有极强的生态适应性并富含多种营养成分和生物活性物质，并以耐干旱、耐瘠薄、萌蘖及固氮能力强等特点被称为治理非宜林地水土流失、改善生态环境的先锋树种。种植沙棘是治理内蒙古脆弱生态环境最经济、最有效的措施，是贫瘠的不毛之地发展经济、增加收入的经济树种。另外．种植沙棘的技术简便，容易掌握，投资少，见效快。     

Structure of a pentacyclic triterpene alcohol fromCentaurea aquarrosa

Summary The structure of a previously unknown pentacyclic triterpene isolated fromCentaurea squarrosa Willd. has been established. It is urs-20(3)-en-3-ol (I).A. L. Mndzhoyan Institute of Fine Organic Chemistry, Academy of Sciences of the Armeniam SSR, Erevan. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 59–69, January–February, 1977.