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We propose a new approach to exploring relativistic compound systems in an external magnetic field. A relativistic Hamiltonian that includes confinement, one-gluon exchange, and spin-spin interaction has been obtained applying the path integral formalism. The masses of the quark-antiquark states that correspond at zero magnetic field to the r- and p-meson and neutron mass have been calculated as a function of the magnetic field. The most interesting phenomena occur in superstrong magnetic fields on the order of 1018 [?] 1020 G that emerge for a short time in peripheral collisions of relativistic heavy ions.

Abstract: Rivers of the Northern Dvina catchment are considered to demonstrate the possibility of obtaining polyvariant estimates of changes in the water regime of rivers in the northern part of the forest zone, which are caused by expected changes in air temperature and precipitation. For this purpose, the dynamic-stochastic modeling approach was applied. The snowmelt and rainfall runoff model developed at the Hydrometeorological Research Center of the Russian Federation was used as a hydrological unit. Meteorological observational data collected during the 50- to 60-year period were statistically expanded by using an approach based on composing artificial variants of the annual cycle of meteorological variables, which can be performed through combining the observed variants of weather conditions of the cold and warm periods. As a result, polyvariant estimates of possible changes in the water regime of rivers corresponding to various scenarios of changes in air temperature and precipitation were obtained.

Abstract: Crystal forms of cobalt(III) tris(2-aminoethanolate) hydrates, i.e., red cubic crystals of the composition fac-[Co(NH2CH2CH2O)3] � 5.44H2O (fac-I � 5.44H2O) and blue prismatic crystals of the composition mer-[Co(NH2CH2CH2O)3] � 3H2O (mer-I � 3H2O) were studied by the 59Co, 13C NMR and X-ray diffraction methods. It was found that mer-[Co(NH2CH2CH2O)3] � 3H2O (mer-I � 3H2O) is a new pseudopolymorphic modification of fac-[Co(NH2CH2CH2O)3] � 3H2O (fac-I � 3H2O), while fac-I � 3H2O represents a new polymorphic modification of the complex mer-[Co(NH2CH2CH2O)3] � 3H2O (mer-I � 3H2O) described previously. The comparative analysis of the spectra revealed dynamic equilibrium between these geometric isomers; the fac-isomer is stable in aqueous solutions.

Abstract The [Co(DH)2(Py)2][H2F3] complex (DH− is the dimethylglyoxime residue) is synthesized and studied by X-ray diffraction analysis. Structural units of the crystal are complex cations [Co(DH)2(Py)2]+ and anions [H2F3]−. Two residues of α-dimethylglyoxime linked by intramolecular hydrogen bonds O-H⋯O lie in the equatorial plane of the octahedral Co(III) complex, and two pyridine molecules occupy the apical positions. The H2F

Abstract The crystal structures of copper(II) nitrate complexes with 2-(2-hydroxybenzylideneamino)-2-hydroxymethylpropane-1,3-diol (HL) and 2-hydroxymethyl-2-(2-hydroxy-5-nitrobenzylideneamino)propane-1,3-diol (HL1) were determined. The resulting complexes were formulated as [Cu3OL3(H2O2]NO3 · 3H2O (I) and [Cu(H2O)L1]NO3 (II). The crystals of I are monoclinic, a = 17.809(4) Å, b = 30.549(6) Å, c = 18.962(4) Å, β = 115.36(3)°, space group Cc, Z = 8, R = 0.0482. Complex I is composed of two independent three-dimensional µ3-oxo complexes; the coordination polyhedron of the copper atoms in both compounds is an elongated tetragonal bipyramid. The coordination polyhedron of the third Cu atom is a tetragonal pyramid. The bases of the pyramids are composed of the oxygen atoms of the phenol and alcohol OH groups, the imine N atom of ligand L, and µ 3-oxo atoms. The phenol and water O atoms serve as the apices in both the tetragonal bipyramids. The crystals of II are triclinic, a = 6.062(1) Å, b = 7.701(2) Å, c = 16.162(3) Å, α = 88.15(3)°, β = 84.94(3)°, γ = 78.13(3)°, space group P1¯, Z = 2, R = 0.0272. Complex II is composed of polymer chains formed by coordination bonds between the copper atom and two O atoms of the amino alcohol in the azomethine of the neighboring complex connected to the initial one by translation along the x axis. These chains are linked through hydrogen bonds involving the oxygen atoms of the NO2 groups. The benzene rings of the azomethine ligands of the adjoining complexes from different chains are antiparallel to each other. The coordination polyhedron of the central atom is an elongated tetragonal bipyramid. Its equatorial plane is formed by the phenol O atom, one of the alcohol O atoms, the N atom of ligand L1, and the O atom of the amino alcohol in the neighboring complex. The apices are the O atom of the water molecule and the O atom of the amino alcohol in the neighboring azomethine molecule. In complexes I and II, the outer-sphere nitrato group mainly serves to unite trimers and polymers in the crystal by means of hydrogen bonds.

Abstract A new heterometallic Bi(III) complex with diethylenetriaminepentaacetic acid anion (Dtpa)5- of the composition [Co(Tsc)3]2[Bi(Dtpa)]2SO4 · 6H2O (I) (Tsc is thiosemicarbazide) is synthesized and its crystal structure is determined. The complex consists of the [Co(Tsc)3]3+ cations, [Bi(Dtpa)]2- and SO42- anions, and crystallization water molecules. The SO42- ion and two water molecules are randomly disordered over two positions. In the complex cation [Co(Tsc)3]3+, the metal polyhedron has fac-form. The carboxyl groups of octadentate (Dtpa)5- ligand in the [Bi(Dtpa)]2- anion are fully deprotonated. The coordination polyhedron of the Bi atom is a distorted bicapped trigonal prism. Thermogravimetric analysis of complex I indicates that its decomposition occurs through several stages, i.e., dehydration, burning of organic ligands, and the formation of inorganic residue.

Abstract The complexes [M(Tsc)2][Cr(Edta)]2, where M is Ni, Cu; Tsc is thiosemicarbazide; Edta4- is the ethylenediaminetetraacetate anion, were synthesized and characterized by X-ray diffraction. The ionic structures are composed of the [M(Tsc)2]2+ cations and [Cr(Edta)]- anions with a component ratio of 1 : 2. The cation has a distorted trans-square coordination. The carboxyl groups of the H4Edta molecule are deprotonated and the ligand is attached to the Cr atom in the hexadentate chelating mode. The cations and anions are linked by a system of hydrogen bonds.

Abstract A new organic compound, 2'-(3,5-dioxo-1,2,4-triazinane-1-yl)acetic acid, was prepared by transit template synthesis, and its crystal structure was determined. The ability of this compound to form stable metal complexes, where it acts as an N,O-chelating ligand, was demonstrated using its Cu(II) compound as an example.

Solutions of RG equations for β(α) and α(Q) are found in the class of meromorphic functions satisfying asymptotic conditions at large Q(resp. small α), and analyticity properties in the Q2plane. The resulting αR(Q) is finite in the Euclidean Q2region and agrees well at Q≥ 1 GeV with the αs(Q).

A Ni(II) complex of the composition Ni(HNta) · 4H2O (I) was synthesized. Its structure was found to consist of neutral mononuclear [Ni(HNta)(H2O)3] complexes and crystallization water molecules. The Ni atom has octahedral surrounding and is coordinated to tridentate-chelate HNta2–ligand through the N atom and O atoms of two deprotonated acetate groups and through the O atoms of three water molecules. The structure of Iwas compared with those of the Zn(HNta) · 4H2O and Co(HNta) · 4H2O complexes isostructural to I. Thermogravimetric method showed that the decomposition of compound Ioccurs through several successive stages of dehydration, deaquation, decarboxylation, and the formation of inorganic residue.

The coordination polymer {[Zn(Pht)(4,4′-Bipy)(H2O)2] · 2H2O}n(where Pht is a doubly deprotonated phthalic acid residue and 4,4′-Bipy is 4,4′-bipyridine) was synthesized and studied by X-ray diffraction. It was shown that both ligands perform a bridging function and unite the Zn atoms into a two-dimensional network with a periodicity of 11.302(2) Å (with 4,4′-Bipy as the bridge) or 7.627(2) Å (with Pht as the bridge). The coordination polyhedron of Zn is a distorted octahedron with C2symmetry. The Zn–N distances in the coordination polyhedron are 2.117(3) and 2.131(3) Å; the Zn–Ocarbdistance is 2.171(2) Å and the Zn–O(w) distance is 2.129(2) Å. The O–H···O hydrogen bonds involving the outer-sphere water molecules combine the polymer layers into a framework.

Anhydrous compound [Co(NioxH)2(Thio)2]2[SiF6] (I) was synthesized. Its structure was determined by X-ray diffraction analysis. The structures and character of intramolecular and intermolecular hydrogen bonds of complex Iand the previously studied [Co(NioxH)2(Thio)2]2[SiF6] · 3H2O complex were compared.

The results of systematic studies into the structures of products formed in reactions between fluorosilicic acid (FSA) and organic bases are presented. Different hydrolytically labile silicon fluoride complexes contained in these products are stabilized. A debatable problem of FSA state in aqueous solutions is discussed in the light of the data obtained.

[Co(DH)2(Py)2]2SiF6· 10H2O and [Co(DH)2(Thio)2]2SiF6· 2H2O · C2H5OH complexes are synthesized and characterized by X-ray diffraction analysis. Two radicals of α-glyoxime linked by hydrogen O–H···O bonds lie in the equatorial plane of the octahedral Co(III) complexes. Intramolecular (π–π and N–H···O) and intermolecular (O–H···F, O–H···O, N–H···F, N–H···O, N–H···S) interactions are discovered in the crystal. The influence of nonvalence interactions on the structures is discussed.

Compounds of the [Co(DH)2A2](BiEdta) · 6H2O type (where DH is the monodeprotonated dimethylglyoxime –ON=C(CH3)–(CH3)C=NOH; A is the o-, m-, or p-toluidine; and Edta is the ethylenediaminetetraacetate(4–) ion) were synthesized and studied. The composition and structures of the complexes were determined from their UV and 1H NMR spectra and from X-ray diffraction data. The isomer [Co(DH)2(o-NH2C6H4CH3)2]2[Bi2(μ-Edta)2(H2O)2] · 10H2O was structurally characterized using X-ray diffraction analysis. The crystals are triclinic: a= 12.153(2) Å, b= 12.824(3) Å, c= 16.215(3) Å, α = 67.73(3)°, β = 86.18(3)°, γ = 66.96(3)°, space group P $$\overline 1$$ , ρ(calcd) = 1.719 g/cm3, Z= 4. The structure is composed of complex binuclear [Bi2(μ-Edta)2(H2O)2]2–anions, [Co(DH)2(o-NH2C6H4CH3)2]+cations, and molecules of crystallization water. The Edta4–anion chelates with the Bi atom in a hexadentate manner (N2O4); the fifth O atom functions as a bridging ligand. The bismuth coordination polyhedron can be regarded as a strongly distorted antiprism. In the octahedral cation, the Co(III) atom coordinates four N atoms of two DH ligands (average Co–N 1.897 Å) and two N atoms of two o-toluidine molecules (Co–N 2.023 Å). Thermolysis of the complexes studied was found to proceed in several successive steps, namely, the deaquation, deamination, and pyrolysis of the ligands.

Iron acetate of composition [Fe3O(CH3COO)6(H2O)3][AuCl4]·6H2O (I) was synthesized and investigated by X-ray diffraction analysis and Mössbauer spectroscopy. The [Fe3O(CH3COO)6(H2O)3]+complex cation has a structure typical for μ3-O bridged trinuclear ferric compounds with iron atoms lying at the vertices of a regular triangle with an oxygen atom at the center. The iron atoms are each coordinated by 4 oxygen atoms of the four bridging carboxylic groups, the μ3-O bridging atom, and the coordinated water molecule in the trans-position to the latter. In the trinuclear cation, the Fe(III) ions are coupled by antiferromagnetic exchange interactions with the exchange parameter J= -29.0 cm–1(HDVV model for D3hsymmetry). The specific role of the solvate water molecules in structure formation is discussed.

A new copper carboxylate polymer with cyanoacetate anion as a ligand was synthesized and studied using X-ray diffraction, IR, and EPR spectroscopy. The crystal is tetragonal: a= 14.702(2) Å, c= 13.470(3) Å, Z= 8, space group I41/a, and R= 0.0634. The copper atoms in the centrosymmetric dimeric fragment have a square-pyramidal surrounding with the CuO4N coordination core and are joined through four bidentate bridging anions of cyanoacetic acid Cu(1)"–O(1A) 1.931(4) Å, Cu(1)"–O(1B) 1.926(4) Å, Cu(1)–O(2B) 2.018(3) Å, Cu(1)–O(2A) 2.036(4) Å, and Cu(1)–N(1A)" 2.206(5) Å). The Cu···Cu" distance in the dimer is 2.709 Å. The copper atom is extended from the mean equatorial plane toward the axial nitrogen atom by 0.23 Å. EPR data confirm strong antiferromagnetic interaction (2J≈ –275 cm–1) between the copper(II) ions of the dimeric fragment, whereas the interaction between the dimers is significantly weaker (J< 0.3 cm–1).

A new inclusion complex, decaazonium tricyclo[28.2.2.213.16]tetratriacontane (L) decatetrafluoroborate decahydrate [(H10L)⋅(BF4)10⋅10H2O] (I), has been prepared and characterized by X-ray crystallography. Crystal data: a= 8.156(2), b= 29.125(6), c= 12.981(3) Å, β = 96.76(3)°, space group P21/c, Z= 2, the final R= 0.0662 for 5376 reflections with I> 2 σ(I) (MoKα radiation). The azamacrocycle of the complex is a 10-charged cation. The components of the supramolecular system in crystal are stabilized by the hydrogen bonds between the macrocycle cations, the water molecules, and the tetrafluoroborate anions. The water molecules make a solvation shell of the macrocycle forming an octahydrate. The tetrafluoroborate anions alternate with the water molecules “stitched” to the macrocycle, forming polymer chains in the directions parallel to the zaxis of the crystal, and serve as bridges between the macrocycle cations related by the cplane. The set of hydrogen bonds including weak ones unite the components of the complex into a three-dimensional framework. All tetrafluoroborate anions in the structure are disordered.

The complex [Zn(Ofpa)2(H2O)4] · 2H2O (Ofpa is 2-formylphenoxyacetate) is synthesized and characterized by X-ray structural analysis and IR spectroscopy. The crystal is monoclinic: a= 25.254(5), b= 6.952(1), c= 13.951(3) Å, β = 116.41(3)°, Z= 4, space group C2/c, R= 0.034. The zinc atom in the centrosymmetric complex is coordinated by two monodentate carboxylate ligands (Zn–O 2.123(1) Å) and by four water molecules (Zn–O 2.085(1) and 2.092(2) Å). The oxygen atom of the aldehyde group is not involved in coordination. Complexes and solvate water molecules in the crystal are united into a three-dimensional framework via hydrogen bonds and π–π interactions.

This paper reports on an X-ray diffraction analysis of host–guest type molecular complexes of 18-crown-6 with 1,2,5-oxadiazole derivatives: ethyl 4-amino-1,2,5-oxadiazole-3-carboxylic ether (1:1) (complex I), 4-(2-chloroethylamino)-1,2,5-oxadiazole-3-carboxylic acid hydrazide (1:2) (complex II), and 4-amino-1,2,5-oxadiazole-3-carboxylic acid amide monohydrate (1:1:1) (complex III). Crystals I are monoclinic with cell parameters a= 8.960(2), b= 18.118(4), c= 14.405(3) Å, β = 106.9(3)°, space group P21/n, R= 0.054 for 4082 reflections. The 18-crown-6 and guest molecules are linked by hydrogen bonds of NH⋯O(crown) and CH⋯O(crown) types based on the “head-to-tail” principle, alternating in infinite chains along the yaxis in the crystal. Crystals II are triclinic with cell parameters a= 8.615(2), b= 9.249(2), c= 10.987(2) Å, α = 106.86(3), β = 95.25(3), γ = 97.74(3)°, space group P1, R= 0.046 for 3006 reflections. The guest molecules are united into dimers by N–H⋯O=C hydrogen bonds. The 18-crown-6 molecules and the dimer associates of the guest form chains along [110] in the crystal. Crystals III are monoclinic with cell dimensions a= 13.238(3), b= 19.004(4), c= 8.485(2) Å, β = 100.75(3)°, space group Cc, R= 0.051 for 2032 reflections. The crown ether molecule is disordered over two positions. The NH⋯O=C and NH⋯N type hydrogen bonds link the guest molecules into chains. The water molecules serve to bridge the chains with crown ether molecules, forming ribbons whose axis lies along the zdirection in the crystal.

A new coordination compound [Co(Pht)(2-MeIm)2] (I), where Pht2–is the deprotonated radical of o-phthalic acid (H2Pht) and 2-MeIm is 2-methylimidazole, was synthesized. Its structure was established using X-ray diffraction analysis. The crystal is orthorhombic: space group Pca21, a= 15.350(3), b= 7.957(2), c= 13.997(3) Å, ρ(calcd.) = 1.505 g/cm3, and Z= 4. The tetrahedral coordination of the Co(II) atom includes two N atoms of two 2-methylimidazole molecules and two oxygen atoms of two carboxyl groups from different acid radicals. The Co–N distances are equal to 2.022(2) and 2.031(2) Å, while the Co–O distances are 1.972(2) and 2.000(2) Å. The carboxyl groups of the Pht2–radical and the aromatic nucleus form angles of 47.2° and 35.9°, whereas the angle formed by the carboxyl groups themselves is 50.3°. Compound Iis a polymer, which is confirmed by the 1,6-bridging function of the o-phthalic acid radical. The Co···Co distance in a chain is equal to 7.367 Å. Separate chains are united in the crystal into a framework via N–H···O hydrogen bonds.

Compounds that form in the CoSiF6· 6H2O–NioxH2–A–water–alcohol system, where A is thiourea (Thio) or triphenylphosphine (PPh3) and NioxH2is 1,2-cyclohexanedione dioxime, were synthesized and characterized by X-ray diffraction analysis. Crystal structures of the [Co(NioxH)2(PPh3)2]SiF5and [Co(NioxH)2(Thio)2]2SiF6· 3H2O complexes were established. In octahedral Co(III) complexes, two radicals of 1,2-cyclohexanedione dioxime are bound by a hydrogen bond and are located in the equatorial plane. The intramolecular (π–π and H bonds) and intermolecular (C–H···F and H bonds) interactions in the crystal are discussed.

7-Bromo-5-phenyl-1,2-dihydro-3H-1,4-benztriazepin-2-one was obtained by thermolysis of the syn-4-phenylsemicarbazone of 2-aminobenzophenone. Its molecular and crystal structure were established by X-ray crystallography. The nature of the hydrogen bonds between molecules of the compound in solution and in the crystalline state was determined by IR spectroscopy and X-ray crystallography.

Abstract: The molecular and crystal structure of the title complex (I) obtained by addition of tin fluoride in a hydrofluoric acid solution to 18-crown-6 in methanol was investigated by X-ray structure analysis. The crystals are monoclinic, space group P21/n, a = 13.497(3), b = 7.806(2), c = 9.892(2) �, β = 95.57(3)�, Z = 2 for C12H32F4O10Sn. In the polymer chain, the crown ether molecules alternate with the inorganic complexes [trans-SnF4(H2O)2] and are linked to them by O-H...O type hydrogen bonds involving the intermediate water molecules. The weak C-H...F interactions bind the chains into the layers which are parallel to the xz plane.

Abstract: The structure of the hetemnuclear iron acetate [Fe2CoO(CH3COO)6(3-Cl-Py)3]·1/4· 3-Cl-y× 1/4(CH3)2CO· 1/2H2O was determined by X-ray structure analysis. The crystal has a molecular structure and is monoclinic with lattice parameters a = 21.034(4). b = 8.398(2), c = 23.360(5) Å, β= 98.28(3)‡, R = 0.0656. space group P21/c. The trinuclear complex [Fe2CoO(CH3COO)6(H2O)3] has a structure typical for iron(III) μ3-O compounds with iron atoms hing at the vertices of the equilateral triangle centered by an oxygen atom. The metal atoms are each coordinated to four oxygen atoms of the four bridging carboxy groups, the bridging oxygen atom (μ3-O), and the coordinated 3-chloropyridine molecule which is trans relative to the latter atom. According to Mössbauer spectroscopy data, the iron(III) ions are in the high-spin state. The value of (μef)mole/μ3 at room temperature and its temperature dependence suggest that the resulting magnetic exchange interaction between the paramagnetic centers of the cluster is antiferromagnetic.

The interaction between BF3(C2H5)2Oand a racemate of 5,7,7,12,12,14-hexamethyl-l,4,8,11-tetraazacyclotetradecane (L) in the presence of air moisture leads to the complex [(LH2) BF4)2-H2O] (I), whose structure was determined by X-ray structure analysis and confirmed by thermogravimetric data. The crystals are monoclinic, C16H40B2F8N4O, space groupP21ln, a-25.570(7), b = 11.231(5), c = 8.715(4) å, α = 97.32(3)‡, Z = 4, the final R value is 0.0753 for 2800 unique reflections. The structure is built from the double-charged organic cations of the tetraazamacrocycle, tetrafluoroborate anions, and water molecules (1:2:1) linked by a system of hydrogen bonds of NH...F, NH...O, and OH...F type, in which all the four macrocycle nitrogens perform the function of proton donors. The macrocycle in the complex has approximately C2symmetry.

Synthesis and X-ray structure analysis of host-guest complexes [(H4L)(SiF6)2-4H2O] (I) and [(H4L)(GeF6)2-4H2O] (II) are reported (L = meso-5,7,7,12,12,14-hexamethyl-l,4,8,11-tetraazacyclo-tetradecane). The crystals of both compounds are triclinic with close unit cell parameters. I: a = 9.576(3), b= 9.217(3), c= 8.334(2) å, α= 105.66(2), Ω= 83.68(2), α = 105.38(2)‡ II: a= 9.627(3), b = 9.358(3), c.= 8.497(4) A, a= 106.02(2), Ω = 83.74(2), α= 106.06(2)‡. The structural units of the crystals are the (H4L)4+cations, the hexafluorosilicate (or hexafluowgemanate) anions, and the water molecules linked by a system of H bonds. The macrocycle in the complexes has C1symmetry. In the inorganic anions, the silicon as well as germanium atom is surrounded by an octahedron of six fluorine atoms.

Inclusion compounds of solvate water molecules in a crystal matrix are investigated by X-ray diffraction analysis of a macrocyclic polyamine decaazatricyclo[28.2.2.213.16]tetratriacontane nanohydrate (I). When included in a crystal, water molecules are bonded by water-water (O-H...O) and water—macrocycle (0-H...N and N-H...O) hydrogen bonds, forming a linear cluster.

The cis-anti-cis diastereomer of dicyclohexano-18-crown-6 with maleic anhydride or formamide gives a crystalline complex of ratio 1:2. The three-dimensional structure of the former was found from x-ray studies. The formation of complexes was used for the separation of the individual cis-syn-cis and cis-anti-cis diastereomers from a mixture. Crystallization of a cis-anti-cis diastereomer from DMFA, DMSO, and N-methylpyrrolidine gave a high melting form.

Isomeric 2,6- and 2,8-diethyl-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-diones were obtained by the reaction of glyoxal with ethylurea, and their crystal structures and IR, Raman, and PMR spectra were studied.

Sodium acetylacetonate reacts with S-metliylisothiosemicarbazidium nitrate and Fe(NO3)3 · 9H2O in ethanol to make [Fe(HL)NO]NO3, in which H3L is bis(S-methyl-isothiosemicarbazone)-2,4-puntandione. The [Fe(HL)NO]+ cation has a square pyramidal structure with the HL2- arranged around the central ion in the basal plane and the nitrogen atom of the NO group in the apical position, with the iron atom diverging from the plane of the base of the pyramid by 0.477 Å. The FeN0 moiety has a linear structure (?FeNO = l72.7°). XRD, IR, and Mössbauer spectroscopy have been combined with calculations on the electronic structure to demonstrate that the Fe-NO bond is covalent.

By the interaction of 1-hydrazinocarbonylinethyl-7-bromo-5-phenyl-1,2-dihydro-3H-1,4-benzodiazepin-2-one with phosgene, the compound 1-[2(2,3-dihydro-1, 3,4-oxadiazolyl-5-one)jmethyl-7-bromo-5-phenyl-1, 2-dihydro-3H-1, 4-benzodiazepin-2-one has been synthesized. Spectroscopic methods and x-ray structure analysis have been used to establish the crystalline and molecular structure of this new derivative of 1, 4-benzodiazepine.

The reaction of diphenic acid dioxatriethylenediimide with a methanolic solution of amines leads to splitting of the imide heterocyclic ring by methanol with the formation of the corresponding amidoester of diphenic acid. Amines catalyze this reaction. 9,10,11,12-Dibenz[a,c]-7,14-diaza-1,4-dioxahexadecane-8,13-dione was obtained from diphenoyl dichloride and the corresponding diamine. An x-ray diffraction study has been carried out

The reaction of 3,6-dioxa-1,8-(di-2,3-dichloromaleimido)octane with 3,6-dioxaoctane-1,8-diamine gave 7,11-diaza-1,4-dioxa-9-en-7,11-oxo-9-chlorobicyclo-[1.2.9]tridecan-8-one. The steric structure of the last was determined by x-ray structural investigation.

The selective basic hydrolysis of 3-acetoxy-7-bromo-5-(o-chlorophenyl)-1-ethoxycarbonylmethyl-1,2-dihydro-3H-1,4-benzdiazepin-2-one has been carried out, resulting in the sequential formation of 3-hydroxy-1-ethoxycarbonylmethyl-, 3-hydroxy-1-methoxycarbonylmethyl-, and 3-hydroxy-1-carboxymethyl derivatives. The structure of the 1-methoxycarbonylmethyl derivatives has been established by x-ray structural analysis.

5-Methyl-1,2-dihydro-3H-1,4-benzodiazepin-2-one, which is an antagonist of 5-aryl-1,2-dihydro-3H-1,4-benzodiazepin-2-ones, was subjected to a complete x-ray diffraction study. The crystals have monoclinic syngony witha = 11.456(5), b = 8.195(3), c = 9.257(4) Å, ? = 93.10(3) °, and space group P21/b. The nonplanar molecules (with a boat conformation) form cyclic dimers by means of NH...O hydrogen bonds (2.937 Å) in the vicinity of the center of symmetry (0, 0, 1/2). Replacement of the phenyl ring in the 5 position by a less bulky methyl group does not lead to appreciable changes in the geometry and conformation of the heteroring. It is assumed that the substituent in the 5 position plays a role in determining the character of the pharmacological action of 1,4-benzodiazepines.

Without Abstract:

Abstract: Bis-condensation of 4-methyl-2,6-diformylphenol with dimethyl N′,N′-hydrazine diacetate gave product I. The structure of I was determined by X-ray analysis. The conformations of the two side chains of dimethyl N′,N′-hydrazine diacetate are significantly different. The position of one chain is fixed by the intramolecular H-bond of O−H.…N type. Due to its conformation, compound I is partly ready for complex formation with d-metals.

1,4-dimethyl-4,5,7,8-tetrahydro-6H-imidazo[4,5-e][1,4]-diazepine-5,8-dithione was synthesized by boiling 1,4-dimethyl-4,5,7,8-tetrahydro-6H-imidazo[4,5-e][1,4]-diazepine-5,8-dione (a cyclic homolog of theobromine) with P2S5. Its molecular and crystal structures were determined by X-ray structure analysis, PMR spectroscopy and the calculations using the MM2 program. The crystals are monoclinic, sp. gr. P21/n with a=9.305(4), b=9.464(3), c=11.628(3) Å, ?-90.49(3)o, Z=4 for C8H10N4S2. M.p. 268–269 °C. The 7-membered heterocycle has a boat conformation in the crystal, while in solution at room temperature it undergoes interconversion. The geometrical parameters of the molecule obtained by X-ray structure analysis, by PMR spectroscopy below the coalescence temperature (290 K), and by MM2 calculations are in good agreement.

The crystal structure of 1,4,7,10,13-pentaoxa-16-(sulfanil)azacyclooctadecane was determined in an x-ray diffraction structural analysis. This structure consists of centrosymmetric hydrogen-bonded dimers of independent 1,4,7,10,13-pentaoxo-16-(sulfanil)azacyclooctadecane molecules and is a host-guest autocomplex, in which the macrocyclic part of the molecule is the host and the sulfanil substituent of another molecule is the guest.