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Dinuclear iron tetranitrosyl complex with the composition [Fe(SPh)(NO)] ( 1) was synthesized and its single crystals and polycrystals were studied by X-ray diffraction, IR spectroscopy, and elemental analysis. The decomposition products of complex 1 were investigated by electrochemical method and mass spectrometry. The mass spectrum of a solution of complex 1 shows two groups of ions: the primary decomposition products of 1 in solution (the complex ions [Fe(SPh)(NO)(NO)], [Fe(SPh)(NO)], and [Fe(SPh)(NO)]) and a series of the ions [FeO + n(NO)] and [FeO + n(NO)] ( n = 0-4), which are formed in secondary reactions. The structures of the complexes, which were formed through the Fe-NO bond dissociation and the replacement of the NO ligand by aqua and oxygen ligands in complex 1, and the structure of the complex [FeO] were studied by quantum chemical modeling. [ABSTRACT FROM AUTHOR]

Imidazo[4,5-b]pyridines are readily annelated (45-50 °C, 24-30 h, MeCN) with cyanoacetylenic tertiaryα-alcohols to give stereoselectively functionalized 1,3-oxazolo[3,2-a]imidazo[4,5-b]pyridines in 50-88% yields. The adducts undergo a facile stereoselective hydrolytic domino rearrangement to functionalized derivatives of 2,3-diaminopyridines. [ABSTRACT FROM AUTHOR]

Abstract: The [2+2]-cycloadducts of DDQ and 2-ethynylpyrroles, upon ethanolysis (reflux, 15min or room temperature, 24h), rearrange from bicyclo[4.2.0]octadienediones to bicyclo[3.2.0]heptadienone- and cyclobutenyl-dihydrofuranone moieties in 55–83% yields, the former rearrangement being the major direction. Benzoquinone ring cleavage is regioselective to afford mostly bicyclo[3.2.0]heptadienone-pyrrole ensembles (85–90% selectivity) in 39–78% yields. The only exception is when the starting compounds contain an ethoxycarbonyl substituent and the pyrrole counterpart is a 4,5,6,7-tetrahydroindole fragment. In this case, the ratio of the rearrangement products is 1:1.2 in a total yield of 83%. An important feature of the dihydrofuranone pathway rearrangement is its 100% diastereoselectivity. [ABSTRACT FROM AUTHOR]

Previously unknown bis[2-(4- tert-butyl)phen]ethylphosphine sulfide is obtained with a high yield from 4- tert-butyl styrene, red phosphorus, and elemental sulfur. Using single crystal XRD, multinuclear NMR, IR, and UV spectroscopy, it is found that the phosphorus atom is four-coordinated in the bis[2-(4- tert-butyl)phen]ethylphosphine sulfide molecule (regardless of the phase state of the compound: crystal, solution). By the example of phosphorylation of bis[2-(4- tert-butyl)phen]ethylphosphine sulfide acetylene in the KOH-DMSO system it is shown that the reaction proceeds by double addition with the participation of phosphorus-centered nucleophiles. [ABSTRACT FROM AUTHOR]

Abstract: The one-pot reaction of natural amino acids (glycine, β-alanine, γ-aminobutyric and ɛ-aminocapronic acids, d,l-valine, d,l-leucine, anthranilic acid) with bielectrophilic acylacetylenes proceeds chemo-, regio- and stereospecifically in the presence of NaOH (45–50°C, 4h, EtOH–H2O) to give (after treatment of the reaction mixture with aqueous HCl) Z-isomers of N-acylvinyl derivatives of amino acids in 87–94% yield. [Copyright &y& Elsevier]

Steric structure of fluorinated 2-arylhydrazono-3-oxo esters was studied by 1H, 19F, and 13C NMR spectroscopy and X-ray analysis. It was found that these compounds in the crystalline state and in solutions in acetone- d6, DMSO- d6, and CDCl3 exist as Z isomers with the ester fragment involved in intramolecular hydrogen bond with the hydrazone NH proton. Exceptions are alkyl 2-arylhydrazono-4,4-difluoro-3-oxobutanoates which exist in acetone- d6 as mixtures of Z and E isomers, the former prevailing. Unlike fluorinated analogs, ethyl 2-(4-methylphenyl)hydrazono-3-oxobutanoate in crystal has the structure of E isomer in which intramolecular hydrogen bond is formed between the NH proton and acetyl carbonyl group. The same compound in acetone- d6, DMSO- d6, and CDCl3 gives rise to a mixture of Z and E isomers, the latter prevailing. [ABSTRACT FROM AUTHOR]

Abstract: 2-Aminobenzoic acid 1 reacts with α,β-acetylenic γ-hydroxy nitriles 4 and 5 to afford 2-[(5-iminio-2,2-dialkyl-2,5-dihydro-3-furanyl)amino]benzenecarboxylates 7 and 8 (yield 73–74%), a new class of unnatural amino acids in a peculiar zwitterionic form, having the positive charge transferred to the remote imino group of the dihydrofuranyl substituent. 3- and 4-Aminobenzoic acids 2 and 3 with α,β-acetylenic γ-hydroxy nitriles 4–6 undergo entirely different transformations to deliver the esters of cyanomethylhydroxyalkyl ketones 9–12, which result from the unusually facile esterification of the hydroxyl function and simultaneous hydration of the triple bond. 4-Aminobenzoic acid 3 is found to be an active organic catalyst for the one-pot conversion of α,β-acetylenic γ-hydroxy nitrile 4 to 5-amino-2,2-dimethyl-3(2H)-furanone 13, in 80% yield. [Copyright &y& Elsevier]

Abstract: Fluorinated enaminoketones, a new type of ligands, bearing two independent coordination centers (polyether''s and fluorinated enaminoketones fragments) have been obtained. The crystal structure of the Cu(II) complex of 1,5-bis-[2-(4′,4′,4′-trifluoro-1′-methyl-3′-oxo-but-1′-enylamino)-phenoxy]-3-oxapentane (10) has been elucidated by X-ray crystallography. The results obtained show that the complex 10 consists of two crystallographically independent molecules C26H24CuF6N2O5 (A and B), and the metal atom in the complex 10 has four-coordinated arrangement, as a polyhedron with a distorted square with two nitrogen and two oxygen atoms located in corners. [Copyright &y& Elsevier]

Abstract: 2-(2-Cyano-1-ethylthioethenyl)pyrroles easy exchange their ethylthio group for hydroxyl (NaOH, H2O–methanol, 40–45°C, 1h) to give 2-(2-cyano-1-hydroxyethenyl)pyrroles, a new family of stable enols, in 50–94% yields. The vinylic nucleophilic substitution proceeds at the double bond of both the starting pyrroles and their cyclic isomers, 3-iminopyrrolizines. X-ray structure analysis and NMR spectra show the enols to be stabilized by exceptionally strong intramolecular H-bonding. [Copyright &y& Elsevier]

The article reports on a study of the structure and properties of the radical cation salt based on pie-donor bis(ethylenedithio)tetraselenafulvalene with tri(dicyanamido)manganate anion. The compound is metallic and superconducting. It is necessary to conduct detailed studies in magnetic fields to clarify the nature of the low-temperature magnetic state and its influence on the conduction system.

5,5-Bis(hydroxymethyl)-2-oxo-[1-(2-trifluoromethyl)-3,3,3- trifluoropropionamido)-1-trifluoromethyl-2,2,2-trifluoroethyl- 1,3,2-dioxaphosphan (CA-423) is an in vitro inhibitor of the Escherichia coli uridine and thymidine phosphorylases. Unlike widely studied nucleoside analogues, this compound binds to the enzymes irreversibly. Its LD50 in mice was 40 mg/kg. Due to the involvement of pyrimidine phosphorylases in carcinogenesis and the relatively low toxicity of CA-423, it is promising for anticancer therapy.

The conformational analysis of estrone and its derivatives has been performed using the crystallographic data. It is shown that the estrone backbone may have four different conformers due to the conformational flexibility of the B- and D-rings. The correlation plots describing the conformations of the B- and D-rings are given. There is no apparent correlation between the nature of the substituent at C (3) and the overall conformation of the estrone backbone. An X-ray analysis of 3-deoxyestrone has also been undertaken. The crystal data are: space group P212121, Z = 4(C18H22O), a 25,240 (3), b 8,049 (2), c 7,002 (3) A, V 1423 A3, dcalc 1,19 g X cm.-3. The final reliability factors are: R 3,71% and Rw 4,23% for 1501 observed reflections measured on an automatic diffractometer.