Crystal and molecular structure of the derivatives of perchlorate (4Н-chromen-4-yl) and (9Н-xanthene-9-yl) triphenyl phosphonium

The X-ray diffraction study of new derivatives of perchlorate (9Н-xanthene-9-yl) and (4H-chromen-4-yl) triphenyl phosphonium is performed. It is demonstrated that the change in the molecular structure leading to a change in the degree of benzoannelation does not affect the phosphorus–carbon bond length. It is determined that perchlorate (2-phenyl-4Н-chromen-4-yl) triphenyl phosphonium сrystallizes as two polymorphs.     

Study of regioselectivity in cyanomethylation of 4-(trifluoromethyl)pyrimidin-2(1Н)-ones

Chemistry of Heterocyclic Compounds - Cyanoacetic acid reacted selectively with 4-(trifluoromethyl)pyrimidin-2(1Н)-ones with the formation of Michael addition–decarboxylation products...     

Cu(II) and Co(II) Complexes with (4Z)-4-[(2-Diethylaminoethylamino)methylene]-5-Methyl-2-Phenylpyrazol-3-one: Synthesis,Magnetic Properties,and Crystal Structures

Russian Journal of Coordination Chemistry - (4Z)-4-[(2-Diethylaminoethylamino)methylene]-5-methyl-2-phenylpyrazol-3-one (НL, product of the condensation of...     

Fused pyrimidine systems: XVI. Electrophilic intramolecular cyclization of 2-(alkenylsulfanyl)pteridin-4(3<Emphasis Type="Italic">H</Emphasis>)-ones

2-[Allyl(but-3-en-1-yl, pent-4-en-1-yl)sulfanyl]pteridin-4(3Н)-ones at heating in polyphosphoric acid undergo an intramolecular cyclization affording respectively 9-methyl-8,9-dihydro-5H-[1,3]thiazolo[3,2-a] pteridin-5-one and 10-methyl(ethyl)-9,10-dihydro-5Н,8Н-[1,3]thiazino[3,2-a]pteridin-5-ones of angular structure. The cyclization of 2-(alkenylsulfanyl)pteridin-4(3Н)-ones under the action of iodine or arylsulfenyl chlorides afforded iodo(arylsulfanyl) derivatives of angularly fuzed thiazolo- and thiazinopteridines.     

New Zn(II) and Cd(II) Coordination Polymers with 1,2-Benzenedicarboxylic Acid: Synthesis and Structures

Russian Journal of Coordination Chemistry - 1,2-Benzenedicarboxylic (phthalic) acid (1,2-BdcН2) and bipyridine ligands are used for the synthesis of the Zn(II) and Cd(II) coordination...     

Synthesis and anti-influenza activity of 2-cyanoethoxy and 2-(1<Emphasis Type="Italic">H</Emphasis>-tetrazol-5-yl)ethoxy derivatives of dammarane-type triterpenoids

A series of 3-(2-1Н-tetrazol-5-ylethoxy- and 2-1Н-tetrazol-5-ylethoxyimino) derivatives of dammarane triterpenoids was synthesized by azidation of 3-(2-cyanoethoxy- and 2-cyanoethoxyimino)-dammaranes. The anti-influenza activity of the prepared tetrazolyldammaranes and intermediate compounds against influenza virus А H1N1 was tested. A considerable antiviral activity was observed for 20(S)-3-(2-1Н-tetrazol-5-ylethoxyimino)-25,26,27-trinor-20,24-olidedammarane (SI 26).     

Complexes of Co(II), Ni(II), and Cu(II) with (Z)-10-(2-(4-Amino-5-Thioxo-4,5-Dihydro-1H-1,2,4-Triazol-3-yl)hydrazono)-9-Phenanthrone: Synthesis,Spectral Studies,and Quantum Chemical Simulation of the Structures

Russian Journal of Coordination Chemistry - The complexes of (Z)-10-(2-(4-amino-5-thioxo-4,5-dihydro-1Н-1,2,4-triazol-3-yl)hydrazono)-9-phenanthrone (HL) with the Co(II), Ni(II), and Cu(II)...     

4-(2-Methoxyphenyl)-5-(thiophen-2-ylmethyl)-2,4-Dihydro-1H-1,2,4-Triazole-3-Thione and Its Complex with Cadmium Chloride: Molecular and Crystal Structures

Russian Journal of Coordination Chemistry - Compound 4-(2-methoxyphenyl)-5-(thiophen-2-ylmethyl)-2,4-dihydro-1H-1,2,4-triazole-3-thione (LН) and its complex with cadmium(II)...     

Crystal structure of α-(N-benzoxazoline-2-one) acetic acid hydrate,solvate, and salts

The crystal structure of α-(N-benzoxazoline-2-one) acetic acid is studied in the following forms: hydrate, solvate with formic acid, organic monoethanolammonium salt (NН₂(CH₂)₂OH) in two polymorphs produced by minor changes in the crystallization temperature, and also its ethylenediammonium salt (NН₂(CH₂)₂NH₂) in the 2:1 ratio, where amino groups participate in the deprotonation of two molecules of α-(N-benzoxazoline-2-one) acetic acid. Weak intermolecular hydrogen and dative bonds in the crystals consisting of different molecules are analyzed.     

Reaction of 2-(nitroamino)pyrimidin-4(3<Emphasis Type="Italic">H</Emphasis>)-one derivatives with arylamines of low basicity in pivalic acid

Pivalic acid was used as a solvent for aminolysis of poly-substituted 2-(nitroamino)-pyrimidin-4(3Н)-one derivatives with arylamines of low basicity. The reaction did not occur in the other solvents or without solvent. Aminolysis products were obtained in 51–59% yields.     

Synthesis and antiviral properties of new derivatives of 2-(alkylsulfanyl)-6-[1-(2,6-difluorophenyl)cyclopropyl]-5-methylpyrimidin-4(3<Emphasis Type="Italic">H</Emphasis>)-one

Based on 2-(2,6-difluorophenyl)acetonitrile a synthesis was performed of new bioisosteric prochiral analogs of anti-HIV-1 active derivatives of 2-alkoxy-6-benzylpyrimidin-4(3Н)-one that we had previously obtained. The study using infected and nonifected strains of cells MT-4 made it possible to find in all prepared compounds a high anti-HIV activity whereas the cytotoxicity of the substances depended strongly on the structure of the alkylsulfanyl fragment of the molecule.     

Effect of sodium borohydride dihydrate aggregation on the barrier to elimination of hydrogen molecule: Quantum-chemical modeling

The successive elimination of Н₂ from NaBH₄ ? 2Н₂O, (NaBH₄ ? 2Н₂O)₂, (NaBH₄ ? 2Н₂O)₄, and (NaBH₄ ? 2Н₂O)₄ · Н₂O complexes has been modeled in the framework of the cluster approach with the use of the 6-31G* basis set and hybrid density functional (B3LYP). Computations show that combination of NaBH₄ ? 2Н₂O into clusters and addition of one water molecule lead to a decrease in potential barriers to elimination of molecular hydrogen to 0.8–0.9 eV. Transformation of two OH groups of the В(OН) ₄ ^- anion to give a В=O double bond with elimination of water molecule in the tetramer (NaB(OH)₄)₄ has been considered.     

Synthesis and intramolecular transformations of 8-substituted 11-nitro-2-phenyl-5,6-dihydro-2H-2,6-methanobenzo[g][1,3,5]oxadiazocin-4(3H)-one diastereomers

The Biginelli reaction between 5-R-salicylic aldehyde (R = H, Me, and Br), α-nitroacetophenone, and urea affords 8-R-11-nitro-2-phenyl-5,6-dihydro-2H-2,6-methanobenzo-[g][1,3,5]oxadiazocin-4(3Н)-ones as mixtures of two diastereomers. The ratio of diastereomers depends on the catalyst (HCl) concentration in the reaction medium. In DMSO and DMF, the resulting compounds undergo oxadiazocine ring opening with establishment of a three-component equilibrium between 4-(2-hydroxy-5-R-phenyl)-5-nitro-6-phenyl-3,4-dihydropyrimidin-2(1Н)-one as the major component and diastereomeric methanobenzoxadiazocines as two minor components. Dilution of these solutions with water favors the oxa-Michael reaction resulting in the reverse transformation of dihydropyrimidinones into the corresponding starting diastereomers.     

Thermodynamic Characteristics of the Resolvation of Glycylglycinate Ions and Their Contribution to the Change in Stability of Complexes with Cu(II) and Ni(II) in Aqueous–Organic Solvents

Russian Journal of Physical Chemistry A - Thermodynamic characteristics (∆G, ∆Н, T∆S) of the resolvation of glycylglycine and its protonated and deprotonated forms in...     

Structure and Conformational Analysis of 5,5-Bis(bromomethyl)-2-phenyl-1,3-dioxane

The structure of 5,5-bis(bromomethyl)-2-phenyl-1,3-dioxane was investigated by the methods of 1Н, ¹³С NMR spectroscopy and X-ray analysis. The molecule exists in the chair conformation with the equatorial phenyl group. The routes of interconversion of the ring, free conformational energy and optimal conformation of the phenyl group were determined using computer modeling by the method of DFT (PBE/3ξ). The results are consistent with the data of X-ray analysis.     

Reaction of S-allyl and propargyl derivatives of 2-thiouracils with hydrobromic acid

Hydrobromic acid reacts with 2-methallylthio- and 2-prenylthio-4(3Н)-pyrimidinones with participation of the double bond to give the products of heterocyclization, and with 2-allylthio- and 2-propargylthio-6-methyl-4(3Н)-pyrimidinones, with the retention of the double bond and the formation of hydrobromides.     

Spirobisheterocyclization of 5-(Methoxycarbonyl)-1<Emphasis Type="Italic">H</Emphasis>-pyrrol-2,3-diones by the action of enaminoesters. Crystal and molecular structure of 1,7-diazaspiro[4.4]nonane

1-Aryl-4-aroyl-5-(methoxycarbonyl)-1Н-pyrrole-2,3-diones react with methyl 4-aryl-2-(arylamino)-4-oxobut-2-enoates with the formation of methyl 1,7-diaryl-4,9-diaroyl-3-hydroxy-2,6-dioxo-1,7-diazaspiro[4.4]nona-3,8-diene-8-carboxylates.     

Dehydrogenation of 1-aryl(hetaryl)-1,2,3,4-tetrahydro-9<Emphasis Type="Italic">H</Emphasis>-β-carboline-3-carboxylic acids and their esters with dimethyl sulfoxide

Oxidative dehydrogenation of 1-aryl(hetaryl)-1,2,3,4-tetrahydro-9Н-β-carboline-3-carboxylic acids derivatives with dimethyl sulfoxide leads to the formation of 1-aryl(hetaryl)-9Н-β-carbolines. Simultaneously with the dehydrogenation decarboxylation occurs. At the oxidation with dimethyl sulfoxide of methyl 1-aryl (hetaryl)-1,2,3,4-tetrahydro-9Н-β-carboline-3-carboxylicates methyl 1-aryl(hetaryl)-9Н-β-carboline-3-carboxylates formed whose hydrolysis afforded the corresponding 1-aryl(hetaryl)-9Н-β-carboline-3-carboxylic acids.     

Reaction 5-(Arylmethylidene)pyrimidine-2,4,6(1<Emphasis Type="Italic">H</Emphasis>,3<Emphasis Type="Italic">H</Emphasis>,5<Emphasis Type="Italic">H</Emphasis>)-triones with L-Proline and Aldehydes

Boiling in toluene of 5-(arylmethylidene)pyrimidine-2,4,6(1H,3H,5H)-triones with L-proline and aldehyde led to the formation of previously unknown substituted 1′-arylhexahydro-1H-spiro[pyrimidine-5,2′-pyrrolysine]-2,4,6(1H,3Н,5Н)-triones.     

Synthesis of 2-amino-5-(2-aryl-2-oxoethylidene)-4-oxo-1<Emphasis Type="Italic">H</Emphasis>-4,5-dihydrofuran-3-carboxylic acids derivatives by recyclization of 5-arylfuran-2,3-diones under the action of cyanoacetic acid derivatives

Recyclization of 5-arylfuran-2,3-diones under the action of ethyl cyanoacetate or of malonic acid dinitrile resulting in the corresponding esters or nitriles of 2-amino-5-(2-aryl-2-oxoethylidene)-4-oxo-1Н-4,5-dihydrofuran-3-carboxylic acids was investigated.