Chiral 4-piperidones and their bicyclic analogs. Strategy of stereoselective synthesis (review)

The principal stereoselective paths of synthesis and the stereochemistry of chiral 4 piperidones and their bicyclic analogs are examined critically in this article.     

A new example of the three-component reaction: nucleophilic ring opening in cyclopropenones by cyanide ions in the presence of water or alcohols

3-Methyl-2,3-diphenyl-and 3-methyl-2-phenylcyclopropenones react with NaCN and water or alcohols as nucleophiles in the presence of NaHSO₄ to give novel compounds, namely, 3-cyano-2,3-diphenylpropionic acid or alkyl 3-cyano-2,3-diphenyl-and alkyl 3-cyano-2-methyl-3-phenylpropionates. A reaction mechanism was proposed. The anti-(R*R*)-diastereomer was found to be the major reaction product. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2066–2069, September, 2005.     

Hexadecabenzyloxy(diphthalocyanines) of rare-earth elements: synthesis and spectroscopic and electrochemical characteristics

Reactions of 4,5-dibenzyloxyphthalonitrile with salts of rare-earth elements afforded symmetrical lutetium, dysprosium, samarium, and neodymium complexes with hexadecabenzyloxy(diphthalocyanine), which are well soluble in organic solvents. The spectroscopic and electrochemical characteristics of the complexes obtained were studied. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2031–2035, September, 2005.     

Synthetic approaches to physiologically active polycyclic compounds: V. Ritter reaction of 4-hydroxyadamantan-2-one

The Ritter reaction of 4-hydroxyadamantan-2-one (with acetonitrile in the presence of boron trifluoride-ether complex and trifluoroacetic acid) takes an unusual path and yields diastereoisomeric 9- methyl-1-(4-oxo-2-adamantyloxy)-8-oxa-10-azatetracyclo[5.3.1^12,6.1^4,11]tridec-9-enes as the major products. Their structure was established by X-ray analysis.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1488–1491.Original Russian Text Copyright © 2004 by Averina, Zefirova, Zefirov, Chekhlov, Shilov, Aldoshin.For communications I-IV, see [1-4].     

Three-component reactions of polynitromethanes with alkynes. The first synthesis of gem-dinitroaziridines

Three-component one-pot reactions of tetranitro- and bromotrinitromethanes with alkoxyacetylenes, mediated by diazomethane or bicyclobutylidene, yielding gem-dinitroaziridines via sequential electrophile transfer followed by [3+2]-cycloaddition, have been studied. A series of novel N-alkoxy-2,2-dinitroaziridines have been prepared by these reactions.     

Analysis of the applicability of a modified Kol'skii's method for dynamic tests of soils in a deformable casing

Results of an experimental and theoretical analysis of Kol'skii's method for dynamic tests of soft soils in an elastic casing are presented. The model proposed by S. S. Grigoryan for a plastically compressible medium with parameters determined in shock-wave experiments was used as the model of a soft soil. The high-rate deformation of the soil was simulated using a modified “Dunamics-2” program package. The numerical calculations performed showed that the compliance of the casing and friction practically do not influence the measured characteristics of the soil and the basic premises of Kol'skii's method are adequate for soft soil too. Institute of Mechanics, Nizhinii Novgorod State University, Nizhnii Novgorod 603600. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 3, pp. 155–162, May–June, 2000.     

Synthesis of Bromoalkenes and Alkylidene Dibromides by Reactions of Carbonyl Compounds with 2,4,4,6-Tetrabromo-2,5-cyclohexadienone in the Presence of Triphenylphosphine

Reactions of aliphatic and aromatic aldehydes with the 2,4,4,6-tetrabromo-2,5-cyclohexadienonetriphenylphosphine complex result in formation of the corresponding geminal dibromides. Ketones react with the same complex to give vinyl bromides.     

Fragmental descriptors in (Q)SAR: prediction of the assignment of organic compounds to pharmacological groups using the support vector machine approach

The structure—activity classification models for prediction of the assignment of organic compounds to 40 pharmacological groups were constructed in the framework of the fragmental approach using the support vector machine technique, the Platt—Wu probabilistic model, and resampling procedure. The models constructed allow one to predict possible types of the side pharmacological effects of drugs.