实例引导与实践促动相结合普通化学教学探讨

在强调化学学科特点和重要性的基础上,通过实例引导型教学与促动学生实践性学习相结合的方式对大学普通化学教学新模式进行了探讨。     

General Meeting of the Division of General and Technical Chemistry of the Russian Academy of Sciences

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General Meeting of the Division of General and Technical Chemistry of the Russian Academy of Sciences     

General model of the opiate pharmacophore

Analysis of experimental data on the correlation of agonistic and antagonistic properties of molecules of the opiate receptor (OR) ligands of various structural classes and the use of the method of superposition of three-dimensional structures allowed one to single out two regions of the opiate pharmacophore in which hydrophobic interactions are implemented fixing molecules of the OR ligands close to the intercellular membrane and transforming them into “pure” agonists. A set of geometrical parameters characterizing arrangement of these regions in space is defined. This set can be used as a criterion for evaluation of the correlation of agonistic and antagonistic properties in the modeling of new types of OR ligands. For Part 1, see Ref. 1. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1253–1260, June, 2008.     

普通化学课程的出路何在

以化学学科的发展和普通化学课程的任务为依据,对现行普通化学课程的改革方案进行了分析和评论,并提出改革普通化学课程的一些看法和建议。     

General approach for the synthesis of polyquinanes

The diborane-mediated reduction of labile β-diketones 4, 5 and 6 has been employed as the key step in the synthesis of the three polyquinanes, all-$\text{cis}$-tetracyclo-[6.6.0.0^1,5.0^8,12]tetradecane 1, all-$\text{cis}$-tricyclo[6.3.0.0^1,5]undecane 2 and all-$\text{cis}$-tetracyclo-[5.5.1.0^4,13.O^10,13]tridecane, staurane 3, respectively.     

General implementation of the relativistic coupled-cluster method

We report the development of a general order relativistic coupled-cluster (CC) code. Our implementation is based on Kramers-paired molecular spinors, utilizes double group symmetry, and is applicable with the full Dirac-Coulomb and several approximate relativistic Hamiltonians. The available methods include iterative and perturbative single-reference CC approaches with arbitrary excitations as well as a state-selective multi-reference CC ansatz. To illustrate the performance of the new code, benchmark calculations have been performed for the total energies, bond lengths, and vibrational frequencies of the monoxides of Group IVa elements. The trends due to the simultaneous inclusion of relativity as well as higher-order electron correlation effects are analyzed. The newly developed code significantly widens the scope of the ab initio relativistic calculations, for both molecules and atoms alike, surpassing the accuracy and reliability of the currently available implementations in the literature.     

General approach for the synthesis of polyquinenes

The syntheses of tetracyclo[6.6.0.0^1,5.0^8,12]tetradeca-3,6,10,13-tetraene 5 and staurane-2,5,8,11-tetraene 6 are described. The key step was the diborane-mediated reduction of the labile β-diketones 13 and 22 to provide the tetrols 11 and 23, respectively. This was followed by removal of four molecules of water from the corresponding tetrols on heating them in HMPA. This technique has also been employed for preparation of the triquinanetrienes 26 and 27. The use of the diborane-mediated reduction of strained β-diketones in combination with the HMPA-promoted elimination of the resulting alcohols provides an extremely versatile route to polyquinenes.     

General Meeting of the Russian Academy of Sciences

Information

General Meeting of the Russian Academy of Sciences     

General Discussion

Dr. Park (University of Wales, Cardiff, U. K.): I should like to take up a point about the two phase-model. It seems to me that all the varieties of this assume something rather peculiar about the initiation. I may be wrong. But is it true that the initiation is assumed to be uniform throughout the whole system?