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1.
É. Kh. Kazakova S. V. Andreeva G. I. Kovylyaeva G. A. Bakaleinik A. N. Vereshchagin 《Russian Chemical Bulletin》1991,40(3):538-543
We have determined the spectroscopic characteristics, the dipole moments, and the Kerr constants of the stereoisomers of the secondary-tertiary diols of the cyclohexane and bicyclo [4.1.0]pentane series: 3,4-dihydroxy-3-carane (I), 3,4-dihydroxy-3-methylnorcarane (II), 3,4-dihydroxy-3-methylnorcarane (III), 4, 5-dihydroxy-3-methylcyclohexene (IV), 3,4-dihydroxy-3-carane (V), 3,4-dihydroxy-3-methylnorcarane (VI), 3, 4-dihydroxy-3-carane (VII), and 3,4-dihydroxy-4-methyl-3-carane (VIII). It was found that the cis diols are more polar than their trans isomers. It was shown by electrical and electrooptical methods that rotamers with a gauche orientation with respect to the tertiary C-O are stable relative to those containing the diol at the ordinary C-C bond of the ring.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 619–625, March, 1991. 相似文献
2.
S. I. Bobrovskii E. V. Babaev Yu. G. Bundel' 《Chemistry of Heterocyclic Compounds》1987,23(2):169-174
Reaction of bromoacetone with the accessible methyl--nitropyridines has given some 6- and 8-nitroindolizines. In the case of ,'-dimethyl--nitropyridines, both the 8- and 6-nitroindolizines were obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 203–208, February, 1987. 相似文献
3.
A. M. Zvonok N. M. Kuz'menok L. S. Stanishevskii 《Chemistry of Heterocyclic Compounds》1988,24(8):839-844
The reaction of -arylacrylyloxiranes with phenyl azide by refluxing in dioxane or toluene leads to -phenylamino--aryl-acrylyloxiranes. Epoxypropionyl- and -hydroxypropionyltriazoles are also isolated when the reaction is carried out in the dark without heating. It is shown that -phenylamino--arylacrylyloxiranes undergo cyclization to 3(2H)-furanones in an acidic medium, whereas they are converted to 2,3-dihydro-4-pyridones under basic-catalysis conditions.Translated from Khimiya Geterotsiklicheskikh Soedineii, No. 8, pp. 1022–1027, August, 1988. 相似文献
4.
Summary By the reaction of dialkyl esters of -hydroxy, ,-trichloroethylphosphonic acid and acetic anhydride in the presence of a few drops of sulfuric acid, the dialkyl esters of -acetoxy-,,-trichloroethylphosphonic acid were obtained in high yields. 相似文献
5.
Conclusion The action of the hexaethyltriamide of phosphorous acid on disulfides containing an ,-dichloro-,,-trifluoroisopropyl group gives the dimer of trifluoromethylthiirene, namely, 2,5-bis(trifluoromethyl)p-dithiine. Oxidation of this dimer by the action of sulfuric acid gives a stable radical-cation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1160–1162, May, 1987. 相似文献
6.
P. N. Kondrat'ev Z. é. Skryabina V. I. Saloutin K. I. Pashkevich N. A. Klyuev G. G. Aleksandrov 《Russian Chemical Bulletin》1990,39(3):561-565
It has been shown that pyrazoles (hydroxypyrazoles) are formed upon reaction of fluorine-containing copper -diketonates (-ketoesterates) with hydrazines and their hydrochlorides. A preparative method has been developed for the synthesis of fluorinated pyrazoles and hydroxypyrazoles via treatment of fluorine-containing -diketonate and -ketoesterate copper compounds with hydrazines. The molecular structure of 1-phenyl-3-octafluorobutyl-5-hydroxypyrazole has been established based on x-ray structural analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 640–645, March, 1990. 相似文献
7.
The thermal properties of -lactoglobulin (-LG) were studied by differential scanning calorimetry (DSC) under different medium conditions.pH, neutral salts, protein perturbants, and polyols all affected the DSC characteristics of -LG. Acylation with fatty acids also changed the thermal properties, particularly peak width at half-height. The results suggest that the structural stability of -LG is controlled by non-covalent forces, particularly electrostatic and hydrophobic interactions. Disulfide bonds did not contribute to the thermal response of -LG. Fatty N-acyl-amino acids caused marked increases in thermal stability and decreases in denaturation enthalpy, and additional peaks were observed in the presence of some palmitoyl derivatives.Contribution No. 2310, Centre for Food and Animal Research.We thank D. Raymond for her excellent technical assistance. 相似文献
8.
Yu. V. Maevskii S. V. Sokolovskaya I. P. Komkov 《Chemistry of Heterocyclic Compounds》1968,4(3):416-417
The cyclization of 1,1-dichloro-5-(2,5-dimethoxyphenyl)-1,3-pentadien-5-one and the product of its partial demethylation leading to the corresponding derivatives of 2-pyrone and 2-(,-dichlorovinyl)-6-methoxy-4-chromanone has been studied. Irradiation causes the dimerization of 1,1-dichloro-5-(2,5-dimethoxyphenyl)-1,3-pentadien-5-one.For part I, see [1]. 相似文献
9.
R. N. Zagidullin 《Chemistry of Heterocyclic Compounds》1989,25(11):1275-1279
A series of alkali and heavy metal dithio- and thiocarbamates based on N-(-aminoethyl)piperazine and its derivatives N-(-piperazinoethyl)imides, N-[(-2,5-dimethyl-1-pyrrolyl)ethyl]piperazine, and N-(-salicylideneaminoethyl)-piperazine is prepared. Methods for preparation of dithio- and thiocarbamates based on piperazine are improved. Alkali metal dithio- and thiocarbamates based on piperazines form polymeric complexes with heavy metals.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1524–1528, November, 1989. 相似文献
10.
The previously unreported N, N-diformyl-, -bipiperidyl has been synthesized by the reaction of ,-bipiperidyl with carbon monoxide under pressure. 相似文献
11.
The direct nitration and acetylation of 1-methyl-, 1-ethyl-, and 1-benzyl-2-[-(2-furyl)vinyl]benzimidazoles has given the corresponding 1-alkyl- and 1-benzyl-2-[-(5-nitro-2-furyl)vinyl]benzimidazoles and 1-alkyl- and 1-benzyl-2-[-(5-acetyl-2-furyl)vinyl]benzimidazoles. The UV spectra of these compounds have been recorded and their ionization constants have been determined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 832–834, June, 1970. 相似文献
12.
The characteristics of crystallization, melting and spherulitic growth of a random propylene copolymer (PRC) containing small amount of ethylene were studied in the presence of a selective -nucleating agent (calcium pimelate). It was established that the products of isothermal and non-isothermal crystallization are very rich in -modification but have mixed polymorphic composition. The formation of -modification may be attributed to -transition on the surface of growing -spherulites resulting in -twin-spherulites. During melting of PRC of -modification, the characteristics observed with -nucleated propylene homopolymers, namely, a -recrystallization of recooled samples and separated melting of non-recooled samples (i.e. the melting memory effect), as well as a -recrystallization leading to a perfection of the structure within the -modification, are also demonstrated. The disturbance of regularity of the polymer chain highly reduces the tendency to -crystallization. In contrast to the observations with propylene homopolymers, the growth rate of -modification (G
) is higher than that of -modification (G
) and no critical crossover temperature can be found (T()=413 K) below whichG
>G
. The experimental results show that a partial disturbance of chain regularity by incorporation of comonomer units considerably reduces the tendency to -crystallization.This research was supported by the National Scientific Research Fund (OTKA), the author is grateful for it. Thanks are due to Professor Géza Bodor for his help in X-ray diffractometric investigations and to Ms. Tünde Lócska for her prudential technical assistance in the optical experiments. 相似文献
13.
Conclusions The chlorination of 3-carene by N-chlorosuccinimide gave (–)-4-chloro-3 (10)-carene, (–)-3,4-dichlorocarane, (+)-3,4-dichlorocarane, and 2,8-dichloro-p-mentha-1(7),5-diene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 206–209, January, 1987. 相似文献
14.
Conclusions The methyl esters of fluorinated -keto acids enter into the Knoevenagel condensation with malonic acid and give fluorinated -hydroxy--carbomethoxy acids, which form copper salts with a ligand:copper composition=1:1. The Cu salts of fluorinated -hydroxy--carbomethoxy acids are photoreduced by alcohols in the presence of UV light to give -hydroxy--carbomethoxy acids and metallic Cu.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1896–1900, August, 1982. 相似文献
15.
Monir Uddin Antonis G. Hatzidimitriou Maria Lalia-Kantouri Chris Tsiamis 《Structural chemistry》1997,8(2):131-139
The infrared and electronic excitation spectra of a series of new nickel(II) chelates containing an-diimine (or nitrogenous base, enR) and the anion of a-dione (1,3-ketoenol or 1,3-ketoester,H) were obtained in the solid state and in solution. The composition and the overall structure of the new chelates in the solid state depends on ligand concentration, the substituents within the-dionato moiety and the counterion present. The IR and electronic excitation spectra of [Ni(enR)2
]NO3 and [Ni(enR)(O2NO)] indicate, in conjunction with other physicochemical measurements, bidentate coordination of the ligands, while the spectral shifts reveal replacement of the (O,O)nitrato group by basic solvents. The existence of the nickel(II) in an octahedral environment is confirmed by an X-ray structure analysis of [Ni(dpamH)2acac]NO3 · CH3OH (monoclinic, space groupP2l/n, a=17.296(1),b=7.462(1),c=21.604(3) å,=95.65(1),Z=4, R=0.0534,Rw=0.0600), where dpamH denotes the 2,2-dipyridylamine. 相似文献
16.
Conclusions Homologs of p-phenoxystyrene that had not been described in the literature have been synthesized: -methyl-p-phenoxystyrene, -ethyl-p-phenoxystyrene, ,-dimethyl-p-phenoxystyrene, -methyl-p-phenoxystyrene, and ,-dimethyl-p-phenoxy styrene. 相似文献
17.
A. I. Ponomarev A. L. Klebanskii Yu. A. Larionova E. B. Dmokhovskaya V. V. Bogdanova I. F. Ermachkova 《Chemistry of Heterocyclic Compounds》1968,4(3):318-320
The cohydrolysis of-cyanoethyl- and-cyanopropylmethyldichlorosilanes with dimethyldichlorosilane has been studied and the optimum conditions ensuring the maximum yield of rings containing cyanoalhyl groups have been determined.B is(-cyanoethyl)hexamethylcyclotetrasiloxane,-cyanopropylpentamethylcyclotetrasiloxane, and bis(-cyanopropyl)hexamethylcyclotetrasiloxane have been obtained for the first time and characterized. 相似文献
18.
Under the action of concentrated sulfuric acid, a series of -alkyl--arylhydrazides of diarylglycolic acids is converted into 1-alkyl-1,2,3,4-tetrahydrocinnolin-3-ones. The reaction takes place through the intermediate formation of a halochromic salt.For Communication LXV, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 844–846, June, 1970. 相似文献
19.
M. O. Taktakishvili T. K. Tsitskishvili V. S. Kikoladze Sh. A. Samsoniya M. N. Preobrazhenskaya 《Chemistry of Heterocyclic Compounds》1990,26(11):1249-1254
The glycosylation reaction of 6-nitroindoline with 5-tritylribose led to the synthesis of the 1--D-ribofuranoside and 1--D-ribopyranoside of 6-nitroindoline, the dehydrogenation of which resulted in the isolation of the corresponding 1--D-ribopyranoside and 1--D-ribofuranoside of 6-nitroindole; the last with protecting groups are suitable for utilization in oligonucleotide synthesis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1500–1506, November, 1990. 相似文献
20.
S. Yu. Ryabova Yu. I. Trofimkin L. M. Alekseeva L. S. Khabarova V. G. Granik 《Chemistry of Heterocyclic Compounds》1991,27(3):278-283
The reaction of 2-(N,N-dimethylaminomethylene)indolin-3-one and 2-methyl-3-ethoxycarbonyl-5-(N,N-dimethyl aminomethylene)-2-pyrrolin-4-one with acyl halides was used to synthesize immonium salts, the aqueous hydrolysis of which leads to 2-formyl-3-hydroxyindole and 4-hydroxy-5 formylpyrrole derivatives. -Cyano--(2-indolyl)- and -cyano--(5-pyrrolyl)acrylic acid derivatives were synthesized by reaction of immonium salts of the pyrrole series, 4 acyloxy-5-formylpyrrole and 2-formyl-3-acyloxyindole derivatives, with compounds that contain an active methylene group.See [1] for Communication 63.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 343–348, March, 1991. 相似文献