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1.
The reaction of methyl -methoxy-, -acetoxy-, and -chloroacrylate with diazomethane proceeds in conformity with the -M orienting effect of the ester group. The resulting 1-pyrazolines are converted to 3(5)-carbomethoxypyrazole at room temperature (the reaction proceeds more readily on heating).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 545–546, April, 1973.  相似文献   

2.
-Chlorodiphenylacetyl chloride reacts with arylhydrazines to give 1-arylamino-3-phenyl-2,3-dihydro-2-indolones, which undergo acetylation at the nitrogen and oxygen and undergo benzoylation at the nitrogen atom.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 488–490, April, 1981.  相似文献   

3.
Oxidative functionalization of the 19-angular methyl group of pregna-D6-pentarane with its subsequent removal gave 16,17-cyclohexano-19-norprogesterone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1636–1638, July, 1990.  相似文献   

4.
-Chloroacrylic acid reacts with triphenylphosphine to give (E)-(2-carboxyvinyl)triphenylphosphonium chloride. The same reaction with -halomethacrylic acids yields, depending on the temperature, either (2-carboxypropenyl)triphenylphosphonium halides or their isomeric (2-carboxyallyl)triphenylphosphonium halides. The possibility of unusual isomerization of the first compounds to the latter is shown. Synthesis of 1,2-(diphenylphosphinoyl)ethane from -chloroacrylic acid is carried out.  相似文献   

5.
Conclusions When heated in the presence of a catalytic amount of BF3 etherate,-trifluoromethyl--diethylamino--fluoroacrylic acid N, N-dimethylamide is reversibly isomerized to-trifluoromethyl--dimethylamino--fluoroacrylic acid N, N-diethylamide. The methyl esters of-trifluoromethyl--diethylammo--fluoroacrylic acid and-trifluoromethyl--phenoxy--fluoroacrylic acid N,N-dimethylamide are not isomerized under the same conditions.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No.1, pp.137–141, January, 1976.  相似文献   

6.
Binary and ternary mixtures of -tocopherol (T), cholesterol and dipalmitoyl phosphatidylcholine (DPPC) in the form of multilamellar liposomes have been investigated by Fourier Transform Infrared Spectroscopy (FTIR). Investigation of frequencies, bandwidths and band shapes of CH2 stretching and scissoring bands indicate that the effect of T is dominant in comparison with cholesterol and T decreases the interaction of cholesterol with phospholipid membranes.  相似文献   

7.
Kinetic parameters were calculated for the electrochemical reduction of oxygen at a glassy-carbon electrode with the generation of superoxide radical anions in a 0.05 M solution of (C2H5)4NI in dimethylformamide in the presence of fat-soluble antioxidants, retinol and -tocopherol. A procedure based on the protonation of the radical anion with antioxidant molecules is proposed for the voltammetric determination of antioxidants to determine milligram amounts of retinol and -tocopherol in model solutions (RSD = 1–2%). The calibration graphs for retinol and -tocopherol are linear in the concentration ranges 9.7 × 10–5–2.3 × 10–3 and 6.2 × 10–4–3.1 × 10–3 M, respectively. The detection limits for retinol and -tocopherol are 4.8 × 10–5 and 4.1 × 10 –4 M, respectively. The procedure was applied to the determination of the active component (retinol and -tocopherol) in pharmaceuticals.Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 1, 2005, pp. 56–59.Original Russian Text Copyright © 2005 by Ziyatdinova, Gilmetdinova, Budnikov.  相似文献   

8.
On the basis of chemical transformations and with the aid of physicochemical results, the structure of glycoside I isolated from the roots of the plantMedicago sativa has been established as hederagin 3-O-[O--L-arabinopyranosyl-(1 2)--D-glucopyranosyl-(1 2)--L-arabinopyranoside] 28-O--D-glucopyranoside. Compound (I), C52H84O22, mp 210–212°C, [] D 21 +38.4° (c 1.48; methanol). Acid hydrolysis of (I) led to hederogenin (II) — C30H48O4, mp 326–330°C, [] D 23 +84.2° (c 0.19; pyridine. The Hakomorimethylation of glycoside (I) yielded the permethylate (IV) — C65H11O22 [] D 23 +41.6° (c 1.79; methanol). The GLC analysis of the products of the methanolysis of compound (IV) showed the presence of 3,4,6-tri-O-methyl-D-glucopyranose, 2,3,4,6-tetra-O-methyl-D-glucopyranose, 3,4-di-O-methyl-L-O-arabinopyranose, and 2,3,4-tri-o-methyl-L-arabinopyranose. The alkaline hydrolysis of glycoside I gave compound (III) with mp 230–233°C, [] D 21 +35.2° (c 0.21; methanol), which was identified as medicoside C. Details of the PMR spectrum are given for compound (IV) and of the IR spectrum for compound (I).Institute of the Chemistry of Plant Substances of the Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 607–610, September–October, 1986.  相似文献   

9.
A radiochemical charged particle activation procedure for the simultaneous production of carrier-free radioisotopes of more than one element in a single target and their subsequent separation through LLX has been demonstrated. The carrier free isotopes,95,96Nb,93,94,95,96,99mTc and94,95,97,103Ru formed through Mo(,pxn), Mo(,pxn) and Mo(,xn) nuclear reactions with 40 MeV -particle as detected by nondestructive -ray spectroscopy, have been effectively separated through LLX using TOA as an anionic extractant. Separation of the bulk matrix of molybdenum from the carrier free products has been monitored radiometrically using isotopic93,99mMo formed through the Mo(,xn) reaction, as radioindicators for the target element. Purity of the separated carrier free radionuclide has been verified by -ray spectrometry.  相似文献   

10.
Calcined Mg-Al hydrotalcites (CHT) with various Mg/Al atomic ratios were prepared and characterized by XRD, BET and TPD of carbon dioxide. The CHT catalysts were utilized for the synthesis of -pentylcinnamaldehyde (-Pc) from benzaldehyde and n-heptaldehyde in a stirred batch autoclave reactor. An increase of Mg/Al atomic ratio of CHT samples results in the apparent enhancement of catalyst basicity with concomitant decrease of surface areas. Both the catalytic activity and the -Pc selectivity increase with the catalyst basicity and the reaction temperature.  相似文献   

11.
3-Benzoyl-1,2-dihydroquinoxalin-2-one reacts with hydrazine and thiosemicarbazide to give the corresponding hydrazone and thiosemicarbazone. The reaction with arylhydrazines yields 3-(-arylazobenzylidene)-1,2,3,4-tetrahydroquinoxalin-2-ones which are tautomeric to the respective arylhydrazones. On heating in boiling acetic acid, the products of both types undergo intramolecular cyclocondensation with formation of 3-phenylpyrazolo[3,4-b]quinoxalines (3-phenylflavazoles). 3-Benzoyl-1,2-dihydroquinoxalin-2-one thiosemicarbazone gives rise to flavazole structure only in the presence of methyl 3-chloro-2-oxo-3-phenylpropionate as a trap of thiocarbamoyl moiety. The cyclization of 3-(-hydrazonobenzyl)-1,2-dihydroquinoxalin-2-one is accompanied by formation of quinoxalyl ketone azine.  相似文献   

12.
Conclusions Epoxidation of 4-chloro-3(10)-carene with peracetic acid gives a mixture of stereoisomeric 4-chloro-3,10-epoxycaranes with preferential formation of the cis isomer.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 832–835, April, 1979.  相似文献   

13.
Summary 1. A method for obtaining amino acid and peptide derivatives of -methyltryptamine have been described.2. In respect of their biological activity, the closest to Indopan are glycyl--methyltryptamine and L--glutamyl--methyltryptamine, which, at the same time, possess a weaker action on the peripheral adrenoreactive system.3. When amino acid residues are introduced into the molecule of -methyltryptamine, not only does the degree of biological activity of the compound change but, in some cases, new biological properties actually appear.Khimiya Prirodnykh Soedinenii, Vol. 3, No. 2, pp. 108–116, 1967  相似文献   

14.
Zusammenfassung Aus [3] und [3][3](1,3)Ferrocenophan wurden die isomeren Carbonsäuren über ihreN,N-Diphenylamide dargestellt und über die -Phenäthylaminsalze in die Antipoden gespalten. Die absoluten Konfigurationen der Säuren (und damit aller Derivate und Folgeprodukte) wurden sowohl durch chemische Korrelation mit Methylferrocen--und-carbonsäuren bekannter Konfiguration als auch durch kinetische Racematspaltung ihrer Anhydride mit (-)--Phenäthylamin ermittelt.Aus der Methylferrocen-1-carbonsäure wurden durch Kettenverlängerung zur Propionsäure, Cyclisierung und Racematspaltung der Ringketone mit Menthydrazid ebenfalls aktive Ferrocenophane gewonnen, und ihre Konfiguration durch chemische Korrelation bestimmt.Die beschriebenen 45 optisch aktiven Ferrocenophanderivate sind wegen ihrer starren Konformation und der dadurch bedingten Fixierung chromophorer Gruppen-vor allem im Vergleich mit analogenhomoanular überbrückten Ferrocenen-für die Diskussion und Interpretation der Ferrocenchiralität von großem Interesse.From [3] and [3][3](1.3)ferrocenophane the isomeric carboxylic acids were preparedvia theirN,N-diphenylamides and resolvedvia the -phenethylamine salts. The absolute configurations of the acids (and thereby of all derivatives and subsequent products) were established both by chemical correlations with methylferrocene--and--carboxylic acids of known configurations and by kinetic resolutions of their anhydrides with (-)-- phenethylamine.From methylferrocene-1-carboxylic acid by chain lengthening, cyclization of the propionic acid and resolution of the ring ketones with menthydrazide, likewise active ferrocenophanes were obtained and their configurations determined by chemical correlations.The described 45 optically active ferrocenophane derivatives are because of their rigid conformations and the thereby caused fixation of chromophoric groups-mainly in comparison with analogoushomoanular bridged ferrocenes-of great interest for the discussion and interpretation of the ferrocene chirality.
Stereochemistry of Metallocenes, 24. (Ferrocenes, 45). Optically Active [3] and [3][3]Ferrocenophanes. 1: Syntheses, Optical Resolution and Absolute Configurations

23. Mitt. (44. Mitt. über Ferrocenderivate):H. Falk, Christine Krasa undK. Schlögl, Mh. Chem.,100, 254 (1969).  相似文献   

15.
Summary During the reaction between aluminum chloride and cyclic dilakylsiloxanes —octamethylcyclotetrasiloxane, octaethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, and hexaethylcyclotrisiloxane —ring opening occurs with the formation of -chloro--dichloroaluminoxydialkylpolysiloxanes, which further split out ,-dichloropolysiloxanes and form cyclic compounds-1-chloro-3,3,5,5-tetramethylcycloaluminoxydisiloxane and 1-chloro-3,3,5,5tetraethylcycloaluminoxydisiloxane. These compounds were separated and characterized in the form of complexes with aluminum chloride.  相似文献   

16.
From the leaves of Algerian ivyHedera canariensis Willd. (fam. Aralaceae) we have isolated 13 triterpene glycosides: the 3-O--L-arabinopyranosides of oleanolic acid (A), of echinocystic acid (B1), and of hederagenin (B2); the 3-O-[O--L-rhamnopyranosyl-(2)--L-arabinopyranoside]s of oleanolic acid (C), of echinocystic acid (D), and of hederagenin (E1); the 3-O--L-rhamnopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--gentiobioside of hederagenin (G1); the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside] 28-O--gentiobioside of hederagenin (G3); the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--gentiobioside]s of oleanolic acid (G2), of echinocystic acid (H1), and of hederagenin (H2); the 3-O-[O--L-rhanmopyranosyl-(12)--D-glucopyranoside] 28-O-(O--L-rhamno-pyranosyl-(14)--gentiobioside] of hederagenin (H2); and the 3-O-(O--L-rhamnopyranosyl-(12)-O-gentiobiosyl)-O-(14)--L-rhamnopyranosyl-(12)-a-L-arabinopyranoside] of hederagenin (G4). The structures of the substances isolated have been established on the basis of chemical transformations and13C NMR spectroscopy.Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 377–383, May–June, 1996. Original article submitted December 3, 1995.  相似文献   

17.
Conclusions The 3BF3·2CH2C1COOH+BF3-2CH3COOH system effectively catalyzes the selective carbonylation of propylene and n-butylenes. At 95–105°C and a CO pressure of 200 atm, with an equimolar ratio catalystolefin water, propylene or mixed n-butylenes give isobutyric or-methylbutyric acid in near-quantitative yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 110–112, January, 1978.  相似文献   

18.
Summary. N-Acyl--hydroxyglycinates were transformed into N-acyl--triphenylphosphonioglycinates by (i) phosphorylation with Ph 3PBr2 in the presence of Et 3N or (ii) in reaction with DCC and Ph 3P·HBF4 in the presence of catalytic amounts of Ph 3P as well as (iii) by a new kind of Mitsunobu reaction with Ph 3P·HBF4 as a nucleophile conjugated acid. The N-acyl--triphenylphosphonioglycinates can be effectively used without isolation for a nucleophilic displacement of the triphenylphosphonium group to obtain corresponding -substituted -amino acid derivatives.  相似文献   

19.
Summary 1. The synthesis of L-(+)--oleoyl--linoleoyl--glycerylphosphorylethanolamine has been effected.2. During the investigations the following substances were isolated and characterized: L--oleoyl--glycerylphosphoryl-N-phthaloylethanolamine and L---linoleoyl--glycerylphosphoryl-N-phthanoylethanolamine.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 2, pp. 80–83, 1966  相似文献   

20.
It is shown that 5-acetamido-6-carbethoxymethylmercaptopyrimidines (IV-VII) a r e formed by reaction of 5-amino-6-mercaptopyrimidines (I-IlI) with -chloro- and -chloro--methylacetoacetic esters in the presence of excess alkali, while 6-methyl-7-carbethoxy-pyrimidothiazines (XI-XIII) are formed in the absence of alkali; under similar conditions, hydroxyamino compounds VIII-X and 6-carbethoxymethylpyrimidothiazines XIV-XVI are obtained from I-III and -chloroacetoacetic ester. 6-Carbethoxy- and 7-carbethoxypyrimidothiazines XVII-XXI were synthesized from I-III and ethyl bromopyruvate, II, and chloroformylacetic ester, respectively.For Communication XV, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1423–1427, October, 1970.  相似文献   

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