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1.
The reaction of 2,4-dichloro-5-(-chloroethyl)pyridine with ammonia and N-ethylaniline, leading to the formation of 5-azaindoline derivatives, has been studied. The processes of the formation of 6-phenylamino and 6-(N-alkyl-N-phenylamino) derivatives of 7-azaindoline, 5-azaindoline, and 5,7-diazaindoline taking place with N-dealkylation and without it have been compared.For part XXVI, see [16].  相似文献   

2.
Two new glycosides have been isolated from the seeds ofCoronilla glauca L. and C. scorpioides Koch: 3-(0-D-glucopyranosyloxy)-14. 15-dihydroxy-19-oxo-5-card-20(22)-enolide (alloglaucoside) and 3-(-D-gluco-ucofuranosyloxy)-5,14,19-trihydroxy-5-card-20(22)-enolide (scorpiosidol), together with a glycoside previously unknown for theCoronilla genus — 3-(-D-glucopyranosylo)g)-14-hydroxy-5-card-20(22)-enolide (desglucouzarin) and known aglycons (corotoxigenin, alloglaucotoxigenin, coroglaucigenin) and glycosides (glucocorotoxigenin, coronillobioside, glucocoroglaucigenin, coronillobiosidol and scorpioside).Ukraine Pharmaceutical Academy, Kharkov–2. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 372–376, May–June, 1996. Original article submitted August 14, 1995.  相似文献   

3.
New triterpene glycosides — salsolosides C and D — have been isolated from the epigeal part ofSalsola micranthera Botsch. On the basis of chemical transformations and physicochemical measurements, salsoloside C has been assigned the structure of oleanolic acid 28-0--D-glucopyranoside 3-0-[0--D-xylopyranosyl-(1 4)--D-glucuropyranoside], and salsoloside D has the structure of hederagenin 28-0--D-glucopyranoside 3-0-[0--D-xylopyranosyl-(1 4)--D-glucuropyranoside].Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 727–732, November–December, 1983.  相似文献   

4.
The roots ofPolygonum coriarum have yielded two oligomeric proanthocyanidins, T1 and T2, and their structures have been established: 3-O-galloyl-7-O-[O-(6-O-galloyl)--D-glucopyranosyl]-(–)-epigallocatechin-(4-8)-(–)-epicatechin-(4-8)-(–)-epicatechin-(4-8)-(–)-epigallocatechin 3-O-gallate (T1) and (–)-epicatechin-(4-8)-[3-O-galloyl-(–)-epigallocatechin]-(4-8)-(–)-epicatechin-(4-8)-(+)-catechin (T2).The material of this paper were presented at the IInd International Symposium on the Chemistry of Natural Compounds (SCNC, Eskisehir, Turkey, October 22–24, 1996).Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 588–593, July–August, 1977.  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.
A general method was developed for the synthesis of 1,6-disubstituted 4-methyl-5-cyano-7-azalndolines from the readily available ammonium salt of 2,6-dihydroxy-3-(-hydroxyethyl)-4-methyl-5-cyanopyridine through the corresponding N-substituted ammonium salts and N-substituted 2-amino-3-(-hydroxyethyl)-4-methyl-5-cyano-6-hydroxypyridines with treatment of the latter by POCl3. This method gives a 40% yield of 4-methyl-5-cyano-7-azaindoline compounds containing various aralkyl or alkyl substituents at N-1 and a hydroxy group or halogen atom at C-6 in three steps.For Communication 65, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 84–88, January, 1985.  相似文献   

7.
The effects of -, -, dm-(heptakis(2,6-di-O-methyl)--) and -cyclodextrins (CD) on the kinetics of the electron-transfer reaction of the ferrocenemonocarboxylate anion (FCA) with bis(pyridine-2,6-dicarboxylato)cobaltate(III) have been investigated in aqueous solution (0.20 M Na2HPO4, pH 9.2) at 25.0°C. Substantial decreases in the rate constants for the electron-transfer reactions were observed upon cyclodextrin inclusion of the reductant, due to an increase in the FCA0/– reduction potential and to the insulation of the reductant from oxidant. The inclusion stability constants for {FCA·CD} were evaluated from the1H NMR and kinetic data, and the order of the stability constants was found to be -CDdm-CD-CD>-CD.  相似文献   

8.
Condensing-alkyl(aryl)--bromo--nitroethylenes with dimedon and dihydroresorcinol gives a number of derivatives of nitrohexahydrobenzofuran, reduced using Raney nickel catalyst, to substituted hexahydroindolones, boiling with the same catalyst in ethanol giving tetrahydroindolones. Acid hydrolysis of derivatives of nitrohexahydrobenzofuran gives monocarboxylic acids (only the furan ring being opened), or dicarboxylic keto-acids (both rings opened). Reaction of nitrohexahydrobenzofurans with p-nitrophenylhydrazine gives monohydrazones. 2-Nitro-3-(m-nitrophenyl)hexahydrobenzofurans, when boiled with excess triethylamine, lose nitrous acid to give 3-(m-nitrophenyl)tetrahydrobenzofurans.  相似文献   

9.
The structure of psolusoside B — a minor triterpene oligoglycoside from the holothurianPsolus fabricii and the main glycoside fromPsolus sp. has been determined by the methods of partial acid hydrolysis, methylation,13C NMR, and FAB mass spectrometry as 20S-acetoxy-3-{2-O-[O--D-glucopyranosyl-(1 4)-O--D-glucopyranosyl]-4-O-(6-O-sulfato--D-glucopyranosyl)--D-xylo-pyranosyloxy}holosta-7,25-diene-18,16-carbolactone. 3-[O-(3-O-Methyl-6-O-sulfato--D-glucopyranosyl)-(1 3)-O-(6-O-sulfato--D-glucopyranosyl)-(1 4)-O--D-quinovopyranosyl-(12)--D-xylopyranosyloxy]holosta-9(11),25-dien-16-one (psolusoside A), known previously forPsolus fabricii, has been identified in a holothurian —Psolus sp. — from Kraternaya Bay (island of Ushishir).Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 361–368, May–June, 1989.  相似文献   

10.
O-octyloxycarbonyl cyclodextrins were immobilised in flat sheetPEEK-WC membranes. The membranes were prepared by phase inversion methodand characterised. cyclodextrin (CD) catalytic action in thep-nitrophenylacetate (PNPA) hydrolysis to p-nitrophenol (PNP) was studied. The CD acylic carbonate derivative shows an effective catalytic action whenincorporated in PEEK-WC membranes, by showing an enzyme-like behaviour. Themembranes were tested at different temperatures and substrate concentrations and thevalue of activation energy for the reaction was estimated. It is well known that CDhave a catalytic action, but their immobilisation in a polymeric matrix enhances thereaction rate, in fact the entrapment optimises the interaction with the substrate andincreases the chemical stability of the catalyst. In addition, CD show morestability when incorporated in the membrane, because of their chemical resistanceto alkaline attack.  相似文献   

11.
In the hydrazinolysis of 6-chloro-3-(-phthalimidoethoxy)-pyridazine a rearrangement takes place with the formation of 6-chloro-3-(-hydroxyethylamino)pyridazine. The action of thionyl chloride on the latter has given 6-chloro-2,3-dihydroimidazo[1,2-b]pyridazmium chloride. The reaction of -hydroxyethylguanidine with 3,6-dichloropyridazine leads to 6-chloro-3-(-hydroxyethylguanidino)pyridazine.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 124–126, January, 1974.  相似文献   

12.
In water at pH 5–6,-(N--chloroethyl-N-methylamino)propylphthalimide (I) alkylates guanosine to give 7-{-[N-methyl-N-(-phthalylimidopropyl)amino]ethyl} guanosine. The latter is converted to 7-{-[N-methyl-N-(-phthalylimidopropyl)amino] ethyl} guanine and 7-[-(N--aminopropyl-N-methylamino) ethyl]guanine. At pH 9, I and its derivatives undergo opening of the phthalimide ring to give o-carboxybenzamido derivatives. The chief transformation of I at pH 6 is self-alkylation to give quaternary ammonium bases. The pK a and true rate constant for ionization of the chlorine of the-chloroethylamino group were determined for I.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 413–418, March, 1973.See [1] for communication VI.  相似文献   

13.
Electropilic substitution (nitration, bromination, and chlorination) of 4-methyl-6-chloro-7-azaindoline (and its N-acetyl derivative) takes place in the 5 position. 4-Methyl-5-amino-7-azaindoline, 4-methyl-5-nitro-7-azaindoline, and 1-acetyl-4-methyl-5-amino-6-chloro-7-azaindoline were obtained by reduction of 1-acetyl-4-methyl-5-nitro-6-chloro-7-azaindoline under various conditions. A method was developed for the preparation of a new three-ring system — 1,2,3-oxadiazolo[5,4-b]-pyrrolo[2,3-e]pyridine.Communication L from the series Derivatives of Azaindoles. See [1] for communication XLIX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 380–384, March, 1977.  相似文献   

14.
The kinetics of the rearrangement of allyl 5-chloro-2-thienyl sulfide and -chloroallyl 2-thienyl sulfide to, respectively, 5-chloro-3-allyl-2-thiophenethiol and 3-(-chloroallyl)-2-thiophenethiol were investigated. It is shown that an acceptor substituent in the allyl group decreases the reactivity of the sulfide significantly, whereas an acceptor in the heterocyclic ring does not have an appreciable effect on it.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 181–183, February, 1982.  相似文献   

15.
Zusammenfassung Unter Verwendung derGrignardschen Reaktion wurden aus 2,4-, 2,5-und 3,4-Dichlor-jodbenzol und Chloral die entsprechenden ,,-Trichlor--[dichlor-phenyl]-äthanole synthetisiert und als Acetate charakterisiert. Das ,,-Trichlor--[3,4-dichlor-phenyl]-äthanol (IV) läßt sich schneller und in besserer Ausbeute aus dem Produkt der Umsetzung von o-Dichlorbenzol mit Chloral in Gegenwart von Aluminiumchlorid isolieren. IV besitzt insektizide Wirksamkeit (Testtiere: Drosophila melanogaster, Blatta orientalis, Phyllodromia germanica, Calandra granaria, Acanthoscelides obtectus, Musca domestica).  相似文献   

16.
Reaction of methyl -D-galactopyranoside (1) with two equivalents oft-butyldimethylchlorosilane yields methyl 2,6-bis-O-(tBDMSi)--D-galactopyranoside (1 b), methyl 3,6-bis-O-(tBDMSi)--D-galactopyranoside (1 c) and methyl 4,6-bis-O-(tBDMSi)--D-galactopyranoside (1 d). Likewise methyl -D-mannopyranoside (6) affords methyl 2,6-bis-O-(tBDMSi)--D-mannopyranoside (6 d) and methyl 3,6-bis-O-(tBDMSi)--D-mannopyranoside (6 b), which can be isomerised withTPP/DEAD to methyl 4,6-bis-O-(tBDMSi)--D-mannopyranoside (6 f). Methyl 6-O-(tBDMSi)--D-galactopyranoside (1 a) and methyl 6-O-(tBDMSi)--D-mannopyranoside (6 a) can be prepared from1 or6 with one equivalent oft-butyldimethylchlorosilane.Without an external nucleophile the sugar derivatives1 a and1 b react withTPP/DEAD to form the 3,4-carbonato--D-galactopyranosides1 h and1 i and the 3,4-carbonato-2-O-ethoxycarbonyl--D-galactoside (1 j). In contrast to the formation of the compound1 i by means ofTPP/DEAD the reaction of1 a withTPP and Di-t-butyl-azodicarboxylate (DTBAD) yields the 2,3-anhydro--D-taloside (4 b) and only a small amount of1 i. The epoxide4 b can be cleaved withp-nitrobenzoylchloride/pyridine to the 3-chloro-3-deoxy-2,6-di-O-p-nitrobenzoyl--D-idoside (5). Reaction of1 c and1 d withTPP/DEAD yields the 2,3-anhydro--D-gulopyranoside (2), which can be transformed with NaN3/NH4Cl to the 2-azido-2-deoxy--D-idopyranoside (3).Likewise6 a and6 d can be converted to the 3,4-anhydro--D-talosides (7 a and7 b). Reaction of7 b or6 d withTPP/DEAD/NH3 leads to 3,4-anhydro-2-azido-2-deoxy--D-galactopyranoside (8) and 3-azido-3-deoxy--D-altropyranoside (10), resp.The epoxide7 b is opened with NaN3/NH4Cl to the 4-azido-4-deoxymannosides (11 a and11 c) and the 3-azido-3-deoxy--D-idopyranoside (12), while the epoxide8 affords the 2,4-di-azido-2,4-dideoxy--D-glucopyranoside (9).Structures were elucidated by1H-NMR-analysis of the corresponding acetates.
H. H. Brandstetter undE. Zbiral, Helv., im Druck.  相似文献   

17.
1,2,5-Trimetnyl- and 1-(-chlorocrotyl)-2,5-dimethyl-5-(-cyanoethyl)-4-piperidones were synthesized and separated into individual isomers. The corresponding isomeric 5-(-carboxyethyl)-4-piperidones were obtained by hydrolysis. The isomeric 1,2,5-trimethyl-3,5-bis(-cyanoethyl)- and 1,2,5-trimethyl-3,3,5-tris(-cyanoethyl)-4-piperidones were synthesized by subsequent cyanoethylation of the individual 1,2,5-trimethyl-5-(-cyanoethyl)-4-piperidone isomers.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 479–481, April, 1971.  相似文献   

18.
A general method is developed for synthesizing methacrylic esters with a 5-, 6-, or 7-membered lactam ring to the carboxyl group, by reacting the sodio-derivatives of the lactams with -chloroethyl methacrylate. The esters synthesized are prone to thermal polymerization, and able to copolymerize with other monomers in the presence of azodiisobutyronitrile. The following copolymers are prepared; -(N-pyrrolidonyl) ethyl acrylate with methyl acrylate, -(N-pyrrolidonyl) ethyl, -(N-2-oxotetramethyleneimino) ethyl, and -(N-2-oxopentamethyleneimino) ethyl methacrylates withmethyl methacrylate.  相似文献   

19.
The effect of 2-hydroxypropyl--cyclodextrin (HP--CyD) on the release of a water-soluble 1-selective adrenoreceptor antagonist, metoprolol (Met), from ternary Met/HP--CyD/ethylcellulose (EC) tablets was investigated. The release rate of Met from the ternary tablets was dependent on amounts of HP--CyD in the tablets, i.e., the rate decreased when small amounts of HP--CyD were added, while large amounts of HP--CyD accelerated the rate. The slowest rate was observed for the tablet consisted of a 30/10/60 weight ratio of Met/HP--CyD/EC. The analyses of the release rates by the Korsmeyer equation and their temperature dependence suggested that Met is released from the EC matrix containing HP--CyD according to the diffusion-controlled mechanism. The water penetration studies and the micro- and macroscopic observations suggested that the retarding effect of HP--CyD is attributable to a viscous gel formation in small pores on the surface of the tablets, where HP--CyD gels may work as a barrier for the water penetration into the tablets and the release of the drug from the tablets. The in-vitro release property of the ternary tablets was reflected in the in-vivo absorption profile in dogs. The results indicated that a combination of HP--CyD and EC is useful for the release control of water-soluble drugs such as Met.  相似文献   

20.
The effect of mechanical grinding on the physicochemical properties of acetaminophen in the presence of three additives,- or-cyclodextrin and microcrystalline cellulose, was studied by using TLC, powder X-ray diffraction analysis, infrared spectroscopy and differential scanning calorimetry. The results indicate that the crystallinity of physical mixtures of acetaminophen and the described additives decreased with increased grinding time and formed an amorphous state when mixtures containing- or-cyclodextrin were ground with acetaminophen. We also found that the acetaminophen molecules could be included step-by-step into the cavity of-cyclodextrin molecules and formed an amorphous inclusion complex.-Cyclodextrin and microcrystalline cellulose did not form an inclusion complex with acetaminophen, but acted only to decrease the crystallinity of the ground mixtures. The mechanical grinding efficiency for acetaminophen was improved in the order of-cyclodextrin -cyclodextrin > microcrystalline cellulose.This paper is part XI of Drug Interaction in Pharmaceutical Formulations.  相似文献   

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