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1.
Triterpene glycosides from Pulsatilla chinensis   总被引:1,自引:0,他引:1  
Four triterpene glycosides were isolated from the roots of Pulsatilla chinensis (Bunge) Regel (Ranunculaceae). Two new glycosides, chinensiosides A (1a) and B (2), were identified as 3-O-[-L-rhamnopyranosyl-(12)--L-arabinopyranosyl]-28-O-[-L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranosyl]-3,23-dihydroxylup-20(29)-en-28-oic acid and 3-O-{-L-rhamnopyranosyl-(12)-[-D-glucopyranosyl-(14)]--L-arabinopyranosyl}-28-O-[-L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranosyl]-3,23-dihydroxylup-20(29)-en-28-oic acid. The other two glycosides were identified as previously known hederasaponin C (3) from Hedera helix and glycoside III (4) from Pulsatilla cernua.  相似文献   

2.
    
Summary By the reaction of -hydroxymethylene- and -dimethylaminomethylene-2,3-polymethylene-3,4-dihydroquinazolin-4-ones with acid anhydrides and primary and secondary amines, the corresponding -acyloxymethylene- and -mono(di)-substituted aminomethylene-2,3-polymethylene-3,4-dihydroquinazolin-4-ones have been synthesized. The addition of hydrocyanic acid (from acetone cyanohydrin) to the double bond of the methylene group of the -hydroxymethylene- and -dimethylaminomethylene-2,3-trimethylene-3,4-dihydroquinazolin-4-ones has led to -[cyano-(hydroxy)methyl1]- and -[cyano(dimethylamino)methyl]-2,3-trimethylene-3,4-dihydroquinazolin-4-ones.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 603–609, September–October, 1978.  相似文献   

3.
The kinetics of aquation of - and - cis[Co(edda)Cl2]–, - cis[Co(edda)(H2O)Cl] and - cis[Co(trien)Cl2]+ were investigated in aqueous mixtures of t-BuOH, MeOH, DMSO, ethylene carbonate and urea. The transfer Gibbs energy values for the reactants, evaluated from the solubility of the complexes, confirm the decisive role of the reactant solvation on the aquation rate.  相似文献   

4.
The previously known glycosides 3-O--L-arabinopyranosyl-28-O-[-L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl]hederagenin and 3-O-[-L-rhamnopyranosyl-(12)-O--L-arabinopyranosyl]-28-O-[-L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl]hederagenin and the new triterpene glycoside tauroside St-H1 — 3-O--D-glucopyransyl-28-O-[-L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl]hederagenin — have been isolated from the stems ofHedera taurica Carr.M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 571–579, July–August, 1993.  相似文献   

5.
1,3-Skeletal rearrangement of N-substituted ketimines via a possible intimate ion pair is discussed. (CH3)3SiCH=C=O (1) reacts with N-(aziridinyl)-triphenylphosphinimine (2) to give N-(1-aziridinyl)-2-trimethylsilylketen-1-imines (3). The compounds3 b, c are thermally labile and do not undergo 1,3-rearrangement but a retro-ene type reaction to yield (CH3)3SiCH2CN and 2,3-diphenyl-2H-azirine (4). Diphenylketene (5) reacts with N-(N, N-dialkylamino)-triphenylphosphinimines (6) to yield -(N-disubstituted-amino)-nitriles (7). , -Dimethyl--(triphenylphosphinimino)-acetonitrile (9) reacts with (5) at room temperature to form , -dimethyl--(2, 2-diphenylketen-1-imino)-acetonitrile (10) which rearranges at 80° to dimethyl diphenylsuccinonitrile (11). The reaction of5 with 7-(triphenylphosphinimino)-7-azabicyclo[4.1.0]heptane (12) gives tetraphenylsuccinonitrile13 and 7-(7-azabicyclo[4.1.0]heptane)-, -diphenylacetonitrile (14). Finally the synthesis of N-acylketenimines (16) from (5) and acyltriphenylphosphinimines (15) is reported.

38. Mitt.:Chr. Ivancsics undE. Zbiral, Mh. Chem.106, 839 (1975).  相似文献   

6.
Summary The synthesis of the following 1, 4-diphosphoinositides has been effected: the - (, -distearoyl) glyceryl ester of myoinositol 1, 4-diphosphate (VI) or (VII) and 1, 4-bis-[ - (, -distearoyl) glycerylphosphoryl] myoinositol (VIII).Khimiya Prirodnykh Soedinenii, Vol. 2, No. 4, pp. 230–233, 1966  相似文献   

7.
Two new glycosides, gomphotin (1) and gomphotoxin (13), and also the known gomphoside (9) have been isolated from the leaves ofGomophocarpus fruticosus. Compounds (1) and (9) contain a 4,6-dideoxyhexosulose residue as the sugar component, and (13) a 6-deoxyhexosulose, which are attached to glycolic OH groups of the aglycons by 3-O-1,2-O-2 (9, 13) and 3-O-1,4-O-2 (1) acetal-ketal bonds. The structures of the new compounds are represented by the names (3-O-1,4-O-2)-(2,3-dihydroxy-4, 6dideoxyhexulosido)-14-hydroxy-5-card-20(22)-enolide* (1) and (3-O-1,2-O-2)-(2,3,4-trihydroxy-6-deoxyhexulosido)-14-hydroxy-5-card-20(22)-enolide* (13).State Scientific Center for Drugs of the Ministry of Health and the National Academy of Sciences of the Ukraine, Kharkov, fax 441118. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 824–832, November–December, 1995. Original article submitted May 22, 1995.  相似文献   

8.
2-Carbethoxy-[11]--cyclothien-1-one, 2-carbethoxycyclopentadecanone, and 2,15-dicarbethoxy-[9,9]--cyclodithiene-1,14-dione were converted to 2-phenyl-1-methyl-[11]--cyclothieno [1,2-d] pyrazol-3-one, 2-phenyl-1-methyl-4,5-tridecamethylenepyrazol-3-one, and 2,16-diphenyl-1, 15-dimethyl- [9,9]-, -cyclodithienobis [(1,2-d, 14,15-d) pyrazole]-3,17-dione, respectively, by condensation with phenylhydrazine and subsequent methylation.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 920–923, July, 1980.  相似文献   

9.
Starting with (±)-7-hydroxy-6-hydroxymethyl-2-oxa-cis-bicyclo[3.3.0]octan-3-one 15,-19-carboxy-20-norprostaglandins F were synthesized.  相似文献   

10.
It is shown with 1-ethoxyisoindolenine that the reaction of lactim ethers with -amino--cyanoacetamide also extends to partly aromatized lactim ethers, although these react much less readily. Condensation of 1-ethoxyisoindolenine with -amino-cyanoacetamide gives 4-carbamido-5-aminoimidazo[1, 2-1, 2]isoindoline, from which a new series of purinoisoindioline derivatives is synthesized.For part V see [2].  相似文献   

11.
Conclusions Two independent methods were found for the preparation of pregn-5-en-3,21-diol-[16,-17-d]-2'-methyloxazoline: 1) by cis-opening of the aziridine ring of the 3;16,17;21-triacetate of 16,17-epiminopregn-5-en-3,21-diol-20-one and 2) by the 21-hydroxylation of pregn-5-en-3-o1-20-one-[16,17-d]-2'-methyloxazoline using iodosobenzoyl diacetate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2138–2141, September, 1984.  相似文献   

12.
As -cyclodextrin (-CD) was added to D2Osolutions of 2-methylnaphthalene, its proton signals shifted to lower fieldsat low concentrations of -CD. At 2.0 × 10-2 moldm-3 of -CD, however, a reverse, higher-field shift wasobserved for the H-8 signal, indicating the formation of 1 : 1 and 2 : 1-CD–2-methylnaphthalene inclusion complexes. Intrinsic chemicalshift differences of all the protons in 2-methylnaphthalene have beenevaluated for both the 1 : 1 and the 2 : 1-CD–2-methylnaphthalene inclusion complexes. These intrinsicchemical shift differences suggest that the first -CD molecule has noselectivity in accommodating one end of uncomplexed 2-methylnaphthalene;-CD binds to a methyl group, as well as a naphthalene ring-end havingno methyl group, to form the 1 : 1 inclusion complex, resulting in theformation of two kinds of 1 : 1 complexes.  相似文献   

13.
Conclusion The reaction of 20,20-dimethoxy-16,17-epoxypregn-5-ene-3,21-diol-20-one with pyridine thiocyanate in the presence of carbethoxyhydrazine proceeds by two competing paths: cisopening of the oxide ring by a -SCN ion at the C17 atom, and substitution of one of the methoxyl groups by -NCS ion. As a result 2,20-dicarbethoxyhydrazones of pregn-5-ene-3,21-diol-20-one-[17,16-d]-1,3-oxathiolan-2-one and 20-methoxy-16,17-epoxypregn-5-ene-3-ol-[20,21-d]-1,3-oxazolidine-2-thione are formed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 911–914, April, 1987.  相似文献   

14.
Zusammenfassung Es wird die Herstellung von Azobenzolgruppen enthaltenden , -Azo-[isobuttersäure-nitril]-derivaten beschrieben. Löst man die Polymerisation von Methacrylsäuremethylester und Styrol radikalisch durch thermischen Zerfall dieser als Starter dienenden Derivate7 und9 g aus, so enthalten die Polymeren covalent gebundene Starterbruchstücke; sie sind colorimetrisch quantitativ meßbar. Jedoch bewirken Nebenreaktionen, daß die Zahl der so bestimmten Starterfragmente nicht identisch ist mit der Zahl der durch Startreaktionen eingeführten Endgruppen.
Synthesis of azobenzene groups-containing , -azoisobutyronitrile derivatives and their use in polymerization
The preparation of derivates of , -azo-bisisobutyronitrile containing azobenzene groups is described. The thermal decomposition of the derivatives7 and9 g in methyl methacrylate and styrene initiates radicalic polymerisation. The polymers contain covalently bound fragments of the initiators, which can be determined by colorimetry. However due to side reactions the number of the detected initiator fragments is not identical with that of the end groups introduced by initiation.


Mit 1 Abbildung

Frau Professor Dr.E. Husemann zum 60. Geburtstage gewidmet.  相似文献   

15.
-Helix peptides bearing one unit of -cyclodextrin (-CD), one unit of pyrene and one unit of nitrobenzene (NB) in their side chains have been designed and synthesized as novel molecule-responsive devices.In both the CD-peptides, -PR17 and -PL17, the NB unit is separated from the CD unit by two turns of the helix. Two reference peptides (PL17, and -P17,) have also been synthesized. The circular dichroism studies in the peptide absorption region (200–250 nm)of -PR17 and -PL17 suggestthat the CD-peptides form stable-helixstructures (83–77%), which was destabilized by accommodating guest molecules (e.g., n-pentanol) into the CD cavity. It suggests that formation of intramolecular host–guest(CD–NB) complex stabilized thehelical structure and exogenous guest molecule excluded the appending NB moiety from inside to outside of the CD cavity, thereby causing destabilization of the helical structure and increasing the random coil content. The ICD spectra of the peptides in the pyrene and nitrobenzene absorption region (250–40 nm) suggest that NB forms inclusion complex with CD. The fluorescence studies revealed that the fluorescence of the pyrene unit is quenched by the NB unit in -PR17 and -PL17. The fluorescence intensity increases with increasing guest concentration for the CD-peptides.This guest-responsiveenhancement in the fluorescence intensity can be explained in terms of increased distance between the pyrene and NB moieties, which is caused by exclusion of the NB moiety from the CD cavity by guest accommodation. Using the guest-responsive fluorescence quenching properties of the CD-peptides, we have obtained binding constants for various short chain alkanols. -PL17 has higher binding affinity to the guest molecules than its isomer, -PR17, indicating that the location of functional groups on the peptide scaffold is important in molecule detection.  相似文献   

16.
In a continuation of the research on use of 20-keto-16,17-epoxysteroid 20-hydrazones for synthesis of 17-thio analogs of 20-ketosteroid 16,17-acetonides [2, 3], we synthesized 5-H-pregnane-3,16,21-trihydroxy-17-thiol-20-one 16,17-acetonide and found methods for its microbiological dehydrogenation and hydroxylation into 4-3-keto-and 9-hydroxy-4-3-keto derivatives.See [1] for Communication 188.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1182–1186, May, 1992.  相似文献   

17.
Five new sulfated derivatives of sokotrasterol and halistanol have been obtained: 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate); 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate) 23-palmitate; 24,25-dimethyl-5-cholestane-2,3,6-triol 3-(sodium sulfate); 24,25-dimethyl-5-cholestane-2,3,6-triol 6-(sodium sulfate); and 24,25-dimethyl-5-cholestane-2,3,6-triol 2,6-di(sodium sulfate). The inhibiting and membranolytic properties of the polysulfated steroids from sponges and their derivatives have been studied. It has been shown that physiological activity in this series of compounds depends on biphilicity.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 441–445, July–August, 1986.  相似文献   

18.
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   

19.
The reactions of 4-bromo-1-(5-nitro-2-furyl)but-1-en-3-one and its 2-methyl and 2-chloro derivatives with thiourea and its N-allyl and N-phenyl derivatives have yielded 2-amino-4-[-5-nitro-2-furyl)-vinyl]thiazole and its - and N-substituted derivatives. 2-Amino-4-[-(5-nitro-2-furyl)vinyl]thiazole and its -methyl derivative have also been prepared by the direct reaction of the corresponding , -unsaturated ketones with bromine and an excess of thiourea in chloroform, as was shown by a comparison of UV spectra. A series of N-acyl derivatives of the aminothiazoles has been obtained. UV and IR spectra are given.  相似文献   

20.
Zusammenfassung Bei der Einwirkung von Schwefel und Ammoniak auf Propiophenon,n-Butyrophenon undi-Butyrophenon entstehen die entsprechenden Thiazoline-(3), deren saure Hydrolyse zu -Mercaptopropiophenon, -Mercapto-n-butyrophenon bzw. -Mercapto-i-butyrophenon führt. Die Dehydrierung dieser -Mercaptoketone mit Schwefel zu Di- bzw. Trisulfiden wird beschrieben. Die Kondensation der -Mercaptoketone mit Ammoniak und einer Oxokomponente führt zu neuen Thiazolinen-(3), von denen die in 2- und 5-Stellung monosubstituierten Vertreter sich mittels Schwefel zu Thiazolen dehydrieren lassen.
The interaction of sulfur and ammonia with propiophenone,n-butyrophenone andi-butyrophenone leads to the corresponding thiazolines-(3). On acid hydrolysis of the latter -mercaptopropiophenone, -mercapto-n-butyrophenone and -mercapto-i-butyrophenone respectively are formed. The dehydrogenation of these -mercaptoketones with sulfur to di- and trisulfides respectively is described. The condensation of the -mercaptoketones with ammonia and oxo-components yields new thiazolines-(3) of which the 2- and 5-monosubstituted compounds can be dehydrogenated to thiazols with elementary sulfur.
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