Phthalones and their structural analogs (review)

This review is devoted to research on the synthesis, reactivities, practical application, and structural problems of compounds of the phthalone series, primarily pyrophthalones and quinophthalones. The properties and peculiarities of the structures of the indicated compounds are compared with structural analogs that contain other heterocyclic substituents and other β-dicarbonyl systems and also with other betainelike derivatives of β-dicarbonyl compounds. Problems in the development of the chemistry of phthalones are discussed.     

Mechanism of hydride transfer in dihydropyridines and their analogs (review)

The literature data of the last 5–7 years from studies of the mechanism of hydride transfer by various chemical and physical methods have been systematized. It has been noted that in the current literature there is no unanimous opinion regarding the nature of hydride transfer, although the data in favor of the stepwise mechanism predominate.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1299–1314, October, 1984.     

Recent advances in the chemistry of nucleosides and their analogs (review)

Methods for the preparation of nucleosides and their analogs, C-nucleosides, and cyclonucleosides, and their properties are reviewed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 723–738, June, 1978.     

Synthesis of racemic 1,2,3,4-tetrahydroisoquinolines and their resolution

1-Aniline-substituted 3,4-dihydroisoquinolines were obtained in various ways using the Bischler-Napieralski reaction. The effect of the protecting group at the aniline nitrogen atom on the course of the reaction has been studied and it was found that the N-phthalyl group was stable under the cyclization conditions. The dihydroisoquinolines were reduced to the racemic 1,2,3,4-tetrahydroisoquinolines which were resolved by crystallization of the diastereomeric tartrates. Two examples of 1,2,3,4-tetrahydroisoquinolines were obtained in optically pure form (>99%ee).Dedicated to Professor M. A. Yurovskaya on her jubilee.Latvian Institute of Organic Synthesis, Riga LV-1006, Latvia. email: peteris@osi.lv. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 348–361, March, 2000.     

Synthesis and oxidative rearrangement of selenenylated dihydropyrans

Selenenylated dihydropyrans prepared by inverse demand hetero-Diels-Alder reactions undergo oxidative rearrangement when treated with H(2)O(2), leading to tetrahydrofuran-2-ones by ring contraction.     

Synthesis of analogs of nucleosides by creation of heterocyclic bases (review)

Primarily the studies of the author dealing with the synthesis of analogs of nucleosides by cyclization of derivatives of monosaccharides, viz., Schiff bases, hydrazones, thioureas, thiocarbamates, thiosemicarbazones, thiobiurets, and keto isothiocyanates, are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 867–877, July, 1981.     

Synthesis of enantiopure ethyl deoxymonate B from allylic sulfinyl dihydropyrans

A completely stereoselective dihydroxylation of a dihydropyranol and a cross-metathesis in the presence of a free homoallylic hydroxyl group are the key steps of a synthesis of enantiopure ethyl deoxymonate B from a sulfinyl dienol.     

Gold(I)-catalyzed synthesis of dihydropyrans

A trinuclear gold(I)-oxo complex, [(Ph3PAu)3O]BF4, serves as the catalyst for the stereocontrolled synthesis of 2-hydroxy-3,6-dihydropyrans from propargyl vinyl ethers. Importantly, the rearrangement proceeds with excellent diastereoselectivity, and the rearrangement of chiral nonracemic propargyl vinyl ethers proceeds with excellent chirality transfer to furnish enantioenriched pyrans. Additionally, the reaction is amenable to the synthesis of spiroketals from appropriately functionalized precursors. In this case, from a linear precursor, in a single step, the bicyclic spiroketal framework is established with complete stereocontrol over three centers and an alkene functional group in the product.     

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.     

Model analogs of nucleic acids (review)

Literature data on the synthesis and investigation of nucleic acid analogs modified with respect to the sugar-phosphate skeleton are examined.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 27–42, January, 1976.     

Synthesis of tetracycline analogs and their bone affinities

Tetracycline analogs were designed and synthesized and their bone affinities were tested on hydroxyapatite. The results showed that the carbonyl-amide-enol structure in A ring and phenol-ketone structure in BCD ring may be responsible for tetracycline＇s high bone affinity and either A ring or BCD ring has a planar conformation is essential. 2007 Ling Ling Weng. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.     

Synthesis of methylene-bis(1-oxy-3,3-dialkyl-1-triazene 2-oxides) and their analogs

Synthetic procedures towards methylene-bis(1-oxy-3,3-dialkyl-1-triazene 2-oxides), the first representatives of a new class of promising exogenous nitric oxide (NO) donors, which can release NO in living organisms, were developed. Synthesis involves the reactions of salts of 1-hydroxy-3,3-dialkyl-1-triazene 2-oxides with either dibromomethane or 1-chloromethoxy-3,3-dialkyl-1-triazene 2-oxides.     

S树兰烯( 烯)类似物的合成

本文报导了树兰烯(即钴钯烯)的几个类似物(6a-d和7a-d)的合成, 并讨论了有关这些化合物的形成反应的构象效应。     

Furyl(aryl)methanes and their analogs. (Review)

The literature data on furyl(aryl)methanes are systematized and analyzed for the first time. Results obtained by the authors on the synthesis, reactions, and application of these compounds are reviewed.Kuban State Technological University, Krasnodar 350072, Russia; Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 867–901, July, 1999.     

Synthesis and transformations of 4(5H)-oxazolones and their salts (review)

The literature data on the synthesis and transformations of 4(5H)-oxazolones and their salts are correlated. An evaluation of the possibilities of the preparative utilization of the examined reactions is given.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 723–740, June, 1991.     

Aza and deaza analogs of purine nucleosides (review)

Methods for the preparation of aza and deaza analogs of purine nucleosides, viz., nucleosides of imidazo[4,5-d]-v-triazines, imidazo[4,5-b]pyridines, and imidazo[4,5-c]pyridines, and their properties are described. References to the synthesis of nucleosides of imidazo[4,5-d]pyridazines, imidazo[4,5-c]pyridazines, and imidazo[4,5-b]pyrazines are also given.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 147–161, February, 1981.     

The diene synthesis reaction and substitutive addition with 2-pyridones and their thio analogs (review)

The literature on the reactions of 2-pyridones and their thio analogs with unsaturated compounds taking place by a mechanism of diene synthesis or of substitutive addition, depending on the structure of the initial components, has been systematized. The basic synthetic directions of the use of these reactions and also the stereochemistry of the diene synthesis with 2-pyridones and 2-thiopyridones are considered.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 3–20, January, 1984.     

Biologically active heterocyclic analogs of thiourea (review)

The results of research carried out in the Scientific-Research Institute of Medicinals (Budapest, Hungary) are correlated. The structures of 2-aminothiazolines, which can exist in the tautomeric 2-iminothiazolidine form, and of the corresponding analogs of the thiazine series and their acyl derivatives are discussed. A new method for the synthesis of 3-aryl-substituted 2-iminothiazolidines and 2-iminoperhydro-1,3-thiazines is examined. Data on the biological activity of some of the investigated compounds are presented.For example, it is known that 2-(octahydro-1-azocinyl)ethylguanidine (guanethidine) has excellent antihypertensive properties [6–8].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 878–888, July, 1978.