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Russian Chemical Bulletin (v.49, #11)

Structure and acid-basic properties of the surface of titanium oxides modified by phosphorus and aluminum and prepared by the alkoxo method by M. V. Tsodikov; O. V. Bukhtenko; E. V. Slivinskii; L. N. Slastikhina; A. M. Voloshchuk; V. V. Kriventsov; L. E. Kitaev (pp. 1803-1807).
An alkoxo method for the preparatio of single-phase titanium oxides modified by phosphorus and aluminum is proposed and the mechanism of oxide formation is investigated. Structural studies showed that the sizes of the anatase microcrystallite grains and mesopores in the systems are characterized by a uniform distribution. The nature of the modifying agent and the conditions of synthesis influence the interatomic distances and the dimension ofc, the tetragonal unit cell constant of anatase.

Keywords: alkoxo method; tetrabutoxytitanium; crystal structure; interatomic distances; adsorption isotherm; mesopores; microcrystallites

A quantum-chemical approach to the analysis of intramolecular interactions using the fragment orbitals and MNDO method. Calculations for vinyl fluoride and vinyl iodide by V. M. Promyslov; P. P. Shorygin (pp. 1808-1814).
A new quantum-chemical method for demarcation between the basic mechanisms of mutual influence of structural fragments in complex organic molecules (inductive effect, conjugation,etc.) and for assessment of their significance for particular physicochemical properties is proposed. The effects of different channels of intramolecular interaction on the molecular geometry and energy, charge distribution, and the molecular orbital structures and energies were considered taking vinyl halides as examples. In systems with an interfragment bond of high polarity, separation of the contribution of the inductive effect is to a great extent meaningless, while π-conjugation can be considered independently. The method allows a more valid interpretation of the results of quantum-chemical calculations in terms of theoretical organic chemistry.

Keywords: semiempirical quantum-chemical calculations; AMI, MNDO, and PM3 methods; fragment orbitals, conjugation, inductive effect, vinyl halides

A simple method for evaluation of the self-consistency of the radial distribution functions and the orientation of water molecules in the first coordination sphere from the results of molecular dynamics calculations by V. E. Petrenko; M. L. Dubova; Yu. M. Kessler; M. Yu. Perova (pp. 1815-1819).
A simple method for determination of the angular orientation of water molecules in the first coordination sphere from the radial distribution functions is proposed. A comparative analysis of the ability of the model potentials of pair interaction to take into account the effects of manybody interactions (MBI) was performed. The responses of the model pair potentials to the MBI effects in the first and second coordination spheres were found to be poorly correlated with each other. It was concluded that it is necessary to derive a new analytical type of potential functions of pair interaction.

Keywords: intermolecular interactions; potential functions of pair interaction; radial distribution functions; computer simulation of liquids

Proton affinities of fluoro derivatives of benzene, toluene, andm-xylene fromab initio MP2 calculations by Yu. A. Borisov (pp. 1820-1822).
The proton affinity (PA) energies of fluoro derivatives of benzene, toluene, andm-xylene were obtained fromab initio MP2-FC/6-31G* calculations and compared with experimental results. Protonated forms of the molecules, resulting from different ways of proton addition, were studied. Relative concentrations of isomeric arenonium ions were calculated and compared with the results of NMR studies on arenonium ions in solutions.

Keywords: ab initio quantum-chemical calculations; MP2 method; fluoro derivatives of benzene, toluene, andm-xylene; proton affinity; isomeric arenonium ions; relative concentrations of isomers

Heteroorganic betaines by M. S. Nechaev; I. V. Borisova; N. N. Zemlyanskii; D. N. Laikov; Yu. A. Ustynyuk (pp. 1823-1830).
The structures of 6,6-dimethyl-6-silafulvene C5H4SiMe2 (3), its donor-acceptor complex with ammonia. C5H4SiMe2·NH3, dimethylfulvene, a number of cyclopentadienylides, methylenetrimethylphosphorane (6), and silicon-containing organophosphorus betaineC5H4SiMe2CH2PMe3 + (13), the product of nucleophilic addition of6 to3, were calculated using the density functional approach. For compound13, the potential energy minimum corresponds to the conformation withgauche-arrangement of the cyclopentadienyl anionie and trimethylphosphonium cationic centers and a C−Si−C−P dihedral angle of 30.5°, which is due to the Coulomb attraction between these centers. According to calculations, betaine13 is rather stable toward decomposition into3 and6H o=42 kcal mol−1, ΔG Δ=30 kcal mol−1). The main channel of thermal decomposition of compound13 involves an intramolecular nucleophilic substitution, which proceeds with elimination of trimethylphosphine and results in 1,1-dimethyl-1-silaspiro[2,4]hepta-4,6-diene, which then undergoes a ready and irreversible isomerization into 6,6-dimethyl-6-silabicyclo[3.2.0]hepta-1,3-diene owing to the [1.5]-sigmatropic shift of the C−Si bond.

Keywords: silaolefins; silafulvene; silicon-containing organophosphorus betaines; nonempirical quantum-chemical calculations; density functional theory

Laser flash photolysis study of the phase transition effect on the kinetics of triplet-triplet annihilation of tetraphenylporphine inn-decanol by P. P. Levin (pp. 1831-1833).
The kinetics of triplet-triplet annihilation of tetraphenylporphine (TPP) inn-decanol was studied by nanosecond laser flash photolysis with monitoring of the transient absorption and concomitant delayed fluorescence in the temperature range from 100 to −100°C. The freezing of the solution results in more than tenfold acceleration of the process within the same reaction mechanism. It is supposed that the phase transition is accompanied by the concentration of the TPP molecules in defect regions of the polycrystalline structure of the frozen alcohol. These domains have a homogeneous nature and are characterized by a high molecular mobility.

Keywords: laser photolysis; triplet-triplet annihilation; tetraphenylporphine; n-decanol; phase transition

Chemical dynamics of ≡SiOC.O radicals grafted on the activated silica surface by V. I. Pergushov (pp. 1834-1837).
The chemical dynamics of≡SiOC.O radicals grafted on the silica surface was studied in the 77–290 K temperature interval. The rotation diffusion coefficients and characteristic times of rotational mobility of the radicals were estimated.

Isomerization ofn-pentane andn-hexane on modified zeolites by T. V. Vasina; O. V. Masloboishchikova; E. G. Khelkovskaya-Sergeeva; L. M. Kustov; J. Houzvicka; P. Zeuthen (pp. 1838-1841).
The activity and selectivity of catalysts based on TsVM (an analog of ZSM-5), Beta, and La-H-Beta zoelites modified by Pt, Pt−Fe, and Pt−Ga were studied in the isomerization of C5 and C6 linear alkanes. The Pt/HTsVM, Pt/H-Beta, and Pt/La-H-Beta catalysts are efficient inn-pentane isomerization, whereas the Pt/H-Beta and Pt/La-H-Beta are most active inn-hexane isomerization. Nearly equilibirum isoparaffin yield at a selectivity of at least 95–96% is reached on these catalysts unlike other zeolite systems. The overall yield of 2,2-and 2,3-dimethylbutanes is 22 wt.%. The hexane isomers are not formed over the Pt/HTsVM catalyst due to the molecular-sieve properties of this type of zcolites.

Keywords: zcolites; modified zcolites; n-pentane; n-hexane; isopentane; isohexanes; isomerization

Oxidation of aliphatic alcohols with the lead tetraacetate—metal halide system under mechanical activation by N. I. Kapustina; V. D. Makhaev; A. P. Borisov; G. I. Nikishin (pp. 1842-1845).
The mechanochemical oxidation ofn-pentanol,n-hexanol, andn-octanol with the Pb(OAc)4-MHal system (M=Li, K; Hal=Cl, Br) in the absence of a solvent affords esters. and secondary alcohols with the composition C8H17OH and C9H19OH give ketones.

Keywords: mechanical activation; oxidation; aliphatic alcohols; lead tetraacetate; metal halide; esters; ketones

Reactions of sulfenamides with alkynes in the presence of phosphorus(v) oxohalides by N. V. Zyk; E. K. Beloglazkina; M. A. Belova; N. S. Zefirov (pp. 1846-1852).
The reactions of alkynes with arylsulfenamides activated with phosphorus oxohalides giving rise to aryl β-halovinyl sulfides were investigated. The reactions with acetylene, oct-1-yne, and oct-4-yne aretrans-stereospecific, whereas the reaction with phenylacetylene afforded a mixture ofcis- andtrans-addition products. The addition to unsymmetrical alkynes yielded a mixture of Markovnikoff and anti-Markovnikoff isomers whose ratio depends on the solvent. Products of addition to oct-1-yne in the presence of catalytic amounts of acids underwent isomerization.

Keywords: arylsulfenamides; phosphorus(v) oxohalides; alkynes; aryl β-halovinyl sulfides; sulfenylation; isomerization

Template effect in the synthesis of formyl derivatives of benzothiacrown compounds by O. A. Fedorova; A. I. Vedernikov; O. V. Yescheulova; P. V. Tsapenko; Yu. V. Pershina; S. P. Gromov (pp. 1853-1858).
The condensation of 3,4-bis(2-haloethoxy)benzaldehydes with acyclic α,ω-alkanedithiols in the presence of alkali metal carbonates in dry ethanol, DMF, MeCN and their mixtures with water gives formyl derivatives of benzothiacrown compounds in high yields. The best results are attained when the radius of the hydrated metal cation fits to the crown ether cavity. In the case of Cs+, high yields were observed for crown ethers of any size and composition; this can be explained by a specific template effect of this cation. The influence of the nature of the leaving group in 3,4-bis(2-haloethoxy)benzaldehydes was established for reactions with dithiols containing no ether oxygen atoms.

Keywords: 3,4-bis(2-haloethoxy)benzaldehydes; α,ω-alkanedithiols; alkali metal carbonates; template effect; formyl derivatives of benzothiacrown compounds

Novel synthesis of 2-arylbenzothiazoles by V. Z. Shirinian; S. Yu. Melkova; L. I. Belen'kii; M. M. Krayushkin (pp. 1859-1862).
A new method for the synthesis of 2-arylbenzothiazoles by the reaction of dibenzyl disulfides witho-aminothiophenol is suggested. A possible mechanism of the new transformation is discussed. 2-Phenylbenzothiazole can also be prepared by reactions ofo-aminothiophenol with benzyl mercaptane or sodium benzyl thiosulfate.

Keywords: 2-arylbenzothiazoles; synthesis; o-aminothiophenol; reactions with dibenzyl disulfides; benzyl mercaptan; and sodium benzyl thiosulfate

Synthesis, structures, and spectral properties of biomimetic azomethine metal chelates with chromophores CuN2S2, CuN2O2, and CuN2Se2. Crystal structure of bis[4-(benzyl)aldimino-3-methyl-1-phenyl-5-pyrazolothiolato]copper(II) by A. I. Uraev; A. L. Nivorozhkin; G. I. Bondarenko; K. A. Lysenko; O. Yu. Korshunov; V. G. Vlasenko; A. T. Shuvaev; V. P. Kurbatov; M. Yu. Antipin; A. D. Garnovskii (pp. 1863-1868).
Copper(II) chelates of composition CuL2 were synthesized based on 4-aminomethylene derivatives of 5-thiopyrazoles (LH). The complexes were studied by UV, IR, ESR, and EXAFS spectroscopy, magnetochemistry, and X-ray diffraction analysis. The coordination polyhedra in the complexes are pseudotetrahedra or octahedra of the types CuN2S2 or CuN4S2, respectively, which are distorted due to the Jahn—Teller effect. The UV and ESR spectra of copper chelates with a six-coordinate metallocycle formed by the N and S atoms of the azomethine ligand and the nitrogen atom of the quinoline substituent (R) of the C=N−R fragment are most similar to the spectra observed for metals involved in the active centers of natural metalloenzymes (“blue” copper proteins).

Keywords: azomethines; copper; pyrazolones; chelates; biomimetic models; “blue” copper proteins; X-ray diffraction analysis; UV; ESR; and EXAFS spectroscopy

Synthesis and properties of homoleptic 2,2′-bipyridyl complexes of rare-earth elements. Crystal and molecular structures of the complexes Ln(N2C10H8)4 (Ln=Sm, Eu, Yb, or Lu) and the ionic complex [Lu(N2C10H8)4][Li(THF)4] by I. L. Fedushkin; T. V. Petrovskaya; F. Girgsdies; V. I. Nevodchikov; R. Weimann; H. Schumann; M. N. Bochkarev (pp. 1869-1876).
Homoleptic 2,2′-bipyridyl complexes of lanthanides (Ln), Ln(bpy)4, were prepared by the reactions of iodides LnI2(THF)2 (Ln=Sm, Eu, Tm, or Yb), LnI3(THF)3 (Ln=La, Ce, Pr, Nd, Gd, or Tb), or bis(trimethylsilyl)amides Ln[N(SiMe3)2]3 (Ln=Dy, Ho, Er, or Lu) with bipyridyllithium in tetrahydrofuran (THF) or 1,2-dimethoxyethane in the presence of free 2,2′-bipyridine. The IR and ESR spectral data, the magnetic susceptibilities, and the results of X-ray diffraction analysis indicate that the complexes of all elements of the lanthanide series, except for the europium complex, contain Ln+3 cations and anionic bpy ligands. According to the X-ray diffraction data, the coordination polyhedra about the Sm and Eu atoms are cubes, whereas the environment about the Yb atom is a distorted dodecahedron. In the ionic complex [Lu(bpy)4][Li(THF)4], the geometry of the [Lu(bpy)4] anion is similar to that of the Lu(bpy)4 complex. The possible modes of charge distributions over the ligands,viz., Ln(bpy2−)(bpy.−)(bpy0)2 and Ln(bpy.−)3(bpy0), are discussed.

Keywords: rare-earth elements; 2,2′-bipyridine; complexes; structure; magnetic properties

Synthesis and crystal structure of a supramolecular adduct of the cubane cluster [CIPdMo3Se4(H2O)7Cl2]+ with macrocyclic cavitand cucurbituril by M. N. Sokolov; D. N. Dybtsev; A. V. Virovets; K. Hegetschweiler; V. P. Fedin (pp. 1877-1881).
A new heterometallic selenide-bridged 60-electron complex containing the cubane cluster fragment [M033-Se)4Pd] was prepared by heating a solution of [Mo3Se4(H2O)9]Cl4 and palladium black in 2M HCl. The cluster complex was isolated from aqueous solutions as a hydrolytically stable supramolecular adduct with macrocyclic cavitand cucurbituril. The molecular and crystal structure of {[ClPdMo3Se4(H2O)7Cl2](C36H36N24O12)Cl}·7H2O were established by X-ray diffraction analysis.

Keywords: selenide clusters; molybdenum; palladium; cucurbituril; X-ray diffraction analysis; supramolecular adduct

Synthesis and structures of complexes ofN-(2-aminoethyl)diaziridines with transition metal salts by A. V. Shevtsov; V. Yu. Petukhova; S. A. Kutepov; V. V. Kuznetsov; N. N. Makhova; N. E. Kuz'mina; G. G. Aleksandrov (pp. 1882-1886).
A series of complexes ofN-(2-aminoethyl)diaziridines with transition metal salts (Zn2+, Cd2+, Ni2+, Co2+, Mn2+, or Fe2+) were synthesized. Their structures were established by IR and NMR spectroscopy. The structure of bis[1,2-bis(2-aminoethyl)diaziridine]cadmium(II) diperehlorate was confirmed by X-ray diffraction analysis.

Keywords: complex formation; N-(2-aminoethyl)diaziridines; bis[1,2-bis(2-amino-ethyl)diaziridine]cadmium(II) diperchlorate; transition metal salts; X-ray diffraction analysis

Synthesis and structures of nickel(II) trimethylacetate dimers with coordinated diamines by A. A. Sidorov; I. G. Fomina; A. E. Malkov; A. V. Reshetnikov; G. G. Aleksandrov; V. M. Novotortsev; S. E. Nefedov; I. L. Eremenko (pp. 1887-1890).
Thermal decomposition of the tetranuclear nickel(II) complex Ni42-o-(NH2)(NHPh)C6H4|2(MeCN)2(μ-OOCCMe3)42-OOCCMe3)2 (I) under an inert atmosphere (o-xylene, 140 °C) was investigated. Under these conditions, the asymmetric binuclear complex Ni|η2-o-(NH2)(NHPh)C6H4‖(η1-o-(NH2))(NHPh)C6H4|(η2,η-O,O-OOCCMe3)(η2-OOCCMe3) (2) was formed at the first stage. Complex2 was converted into the symmetric dimer Ni|η1-o-(NH2)(NHPh)C6H4|(μ-OOCCMe3)4 (3) upon recrystallization from benzene. The structures of complexes2 and3 were established by X-ray diffraction analysis.

Keywords: carboxylate complexes of nickel; synthesis; structure; magnetic properties

The synthesis ofN-acetyl-β-l-fucosamine-1-phosphate and uridine 5′-diphospho-N-acetyl-β-l-fucosamine by P. A. Illarionov; V. I. Torgov; I. Hancock; V. N. Shibaev (pp. 1891-1894).
Uridine 5′-(2-acetamido-2,6-dideoxy-β-l-galactopyranosyl) diphosphate (uridine 5′-diphospho-N-acetyl-β-l-fucosamine) was synthesized. The key intermediate, 3,4-di-O-acetyl-2-azido-2,6-dideoxy-β-l-galactopyranosyl dibenzyl phosphate, was prepared by a previously unknown reaction of cesium dibenzyl phosphate with the corresponding α-glycosyl nitrate and was then converted into theN-acetylated glycosyl phosphate and nucleoside diphosphate sugarsvia 3,4-di-O-acetyl-2-amino-2,6-dideoxy-β-l-galactopyranosyl phosphate using mildN-acetylation andO-deacetylation as the last synthetic steps.

Keywords: glycosyl phosphates; sugar nucleotides; amino sugars; N-acetyl-l-fucosamine; phosphorylation

The use of cesium dibenzyl and diphenyl phosphates for stereoselective synthesis of glycosyl phosphate derivatives by P. A. Illarionov; V. I. Torgov; V. N. Shibaev (pp. 1895-1898).
Peracetates of β-glycosyl dibenzyl phosphates are formed efficiently in the reaction of cesium dibenzyl phosphate with peracetyl-α-glycosyl nitrates derived froml-fucopyranose,d-galactopyranose, and 2-azido-2-deoxy-d-galactopyranose or with tri-O-acetyl-α-l-fucopyranosyl bromide. On the contrary, the reaction of the above-mentioned glycosyl nitrates with cesium diphenyl phosphate leads to thermodynamically more stable α-glycosyl diphenyl phosphatevia intermediate formation of the corresponding β-anomers.

Keywords: glycosyl nitrates; glycosyl phosphates; phosphorylation; stereospecificity

Synthesis of derivatives of (S)-2-alkanols, components of pheromones ofDrosophila mulleri andRhyzopertha dominica, from (S)-(+)-3,7-dimethylocta-1,6-diene by G. Yu. Ishmuratov; R. Ya. Kharisov; O. V. Botsman; V. V. Zorin; G. A. Tolstikov (pp. 1899-1901).
Effective routes for the synthesis of (S)-2-acetoxytridecane, the sex pheromone of the fruit flyDrosophila mulleri, and (S)-1-methylbutyl 2-methyl- and 2,4-dimethylpent-2E-enoates, components of the aggregation pheromone of the lesser grain borerRhyzopertha dominica, were developed on the basis of (S)-4-methylhex-5-en-1-yl tosylate accessible from (S)-(+)-dihydromyreene.

Keywords: (S)-2-acetoxytridecane; (S)-tridec-2-yl acetate; (S)-(+)-3,7-dimethylocta-1,6-diene; dominicalur; (S)-4-methylhex-5-en-1-ol; (S)-pentan-2-ol; cross-coupling; Baeyer-Villiger reaction; Wacker-Tsuji reaction; pheromone

Synthesis of two new chloro derivatives of the guaianolide grossmisin and the crystal structure of one derivative by O. V. Alebastrov; S. A. Pigiltsova; G. A. Atazhanova; V. A. Raldugin; M. M. Shakirov; I. Yu. Bagryanskaya; Yu. V. Gatilov; A. T. Kulyjiasov; S. M. Adekenov; G. A. Tolstikov (pp. 1902-1904).
The reaction of grossmisin (8α-hydroxyachillin,1) with chlorine in benzene afforded a mixture of products. The less polar product readily crystallized after chromatography. According to the X-ray diffraction data, this product has the structure of 1α,10β-dichloro-1,10-dihydrogrossmisin. The second chloro derivative of grossmisin,viz., 8β-chloroachillin, was prepared in good yield by the reaction of lactone1 with PCl5 in CHCl3 in the presence of Py.

Keywords: sesquiterpenoids; guaianolides; grossmisin; chlorination; X-ray diffraction analysis; two-dimensional NMR spectroscopy

New flavonoid oligoside fromAconitum barbatum Pers. by N. N. Pogodaeva; S. V. Fedorov; L. V. Kanitskaya; A. A. Semenov (pp. 1905-1909).
A new flavonoid oligoside,viz. 3-O-[3,4-)di-O-acetyl-β-xylopyranosyl)-α-rhamnopyranosyl]-7-o-(α-rhamnopyranosyl)kaempferol, was isolated from the above-ground part of the plantAconitum barbatum Pers. The product was identified by spectral methods.

Keywords: Aconitum barbatum ; flavonoids; glycosides; 1H and13C NMR spectroscopy; FAB mass spectrometry

3-(1, 1-Dialkyl-2-hydroxyethyl)-5-hydroxyamino-5-triflouromethyl-Δ2-isoxazolines: The first representatives of β-dioximes existing in the cyclic form: The first representatives of β-dioximes existing in the cyclic form by V. Ya. Sosnovskish; S. Foro; H. J. Lindner; I. I. Vorontsov; Yu. A. Azev (pp. 1910-1913).
It was demonstrated by X-ray diffraction analysis that the reaction of 3,3-dimethyl-6-trifluoromethyl-2,3-dihydro-4-pyrone with hydroxylamine afforded 5-hydroxyamino-3-(2-hydroxy-1,1-dimethylethyl)-5-trifluoromethyl-Δ2-isoxaline.

Keywords: 3-(1, 1-dialkyl-2-hydroxyethyl)-5-hydroxyamino-5-triflouromethyl-Δ2-isoxazolines; X-ray diffraction analysis

Synthesis and IR spectra of 5-phenyl-2-(1-phenyl-2-trichloroacetylethenyl)pyrrole by N. N. Chipanina; Z. V. Stepanova; G. A. Gavrilova; L. N. Sobenina; A. I. Mikhaleva (pp. 1914-1916).
5-Phenyl-2-(1-phenyl-2-trichloroacetylethenyl)pyrrole was synthesized by the reaction of 2-phenylpyrrole with 1-phenyl-2-trichloroacetylacetylene on silicon oxide. The structure of an intramolecular proton-transfer H-complex was assigned to the title compound based on analysis of its IR spectra in solutions in the temperature range of 165–298 K.

Keywords: 2-(2-acylethenyl)-5-phenylpyrroles; proton transfer; intramolecular H-complex; IR spectra

Synthesis of substituted 2-amino-1,3-thiazine-6-thiones by T. E. Glotova; T. N. Komarova; A. S. Nakhmanovich; V. A. Lopyrev (pp. 1917-1918).
The reaction of thiourea with l-acyl-2-bromoacetylenes in AcOH in the presence of BF3·Et2O affords 2-amino-4-phenyl(2-thienyl)-1,3-thiazine-6-thiones in high yields.

Keywords: 1-acyl-2-bromoacetylenes; thiourea; intramolecular cyclization; 2-amino-4-phenyl-1,3-thiazine-6-thione; 2-amino-4-(2-thienyl)-1,3-thiazine-6-thione

Different reactivities of regioisomeric azimines, adducts of phthalimidonitrene with 5-bromospiro[1-pyrazoline-3,1′-cyclopropane] by Yu. V. Tomilov; I. V. Kostyuchenko; E. V. Shulishov; B. B. Averkiev; M. Yu. Antipin (pp. 1919-1922).
The addition of the phthalimidonitrene fragment, resulting from oxidation ofN-aminophthalimide by lead tetraacetate at −20 to −30°C, to the N=N-bond of 5-bromospirol[l-pyrazolinio-3,1′-cyclopropane] (1) affords, apart from the stable 5-bromo-N {spiro[l-pyrazolinio-3,1′-cyclopropane]}-N-phthalimidoamide (azimine2), regioisomeric azimine3, which is completely transformed into 3-acetoxy-N-{spiro[l-pyrazolinio-5,1′-cyclopropane]}-N-phthalimidoamide (4) under the reaction conditions. The acetoxy group in this product easily undergoes nuclcophilic substitution on treatment with McOH, NaN3, or the starting bromopyrazoline1. The structures of azimines obtained were established using NMR spectra, and the structure of the product of reaction of4 with1 was additionally proved by X-ray difraction data.

Keywords: 5-hromospiro[l-pyrazoline-3,1′-cyclopropane]; 3-substitutedN-{spiro[l-pyrazolinio-5,1′-cyclopropane]}-N-phthalimidoamides (azimines); nuclcophilic substitution; NMR spectra; X-ray diffraction analysis

A new phytoecdysteroid by V. N. Odinokov; I. V. Galyautdinov; A. A. Fatykhov; L. M. Khalilov (pp. 1923-1924).
A new phytoecdysteroid,viz, 2-deoxy-3-epi-4β, 20-dihydroxycedysone ((20R,22R)-3α,4β 14α,20,22,25-hexahydroxy-5β-cholest-7-en-6-one), named coronatasteronc, was isolated fromSerratula coronata and identified by NMR spectroscopy.

Keywords: Serratula coronata ; phytosteroid; 20-hydroxyecdysone; 2-deoxy-3-epi-4β, 20-dihydroxyecdysone (coronatasterone); 1H and13C NMR spectra

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