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1.
Fluoroalkyl -alkyl--aminovinyl ketones react with hydrazine hydrate to give the respective razoles and with phenylhydrazine they form a mixture of pyrazoles and 5 hydroxy-2-pyrazolines. Alkyl(aryl) -fluoroalkyl--aminovinylketones do not react with the hydrazines mentioned above. With 2,4-dinitrophenylhydrazine, both types of fluoroalkyl-containing -aminovinyl ketones give only hydrazones of the corresponding methyl alkyl(aryl) ketones.  相似文献   

2.
A new glycoside (cyclofoetoside B) (I) has been isolated from the epigeal part of the plantThalictrum foetidum L. (Ranunculaceae). On the basis of chemical transformations and with the aid of physicochemical characteristics it has been established that cyclofoetoside B is 24S-cycloartane-3, 16, 24, 25, 29-pentaol 3-O--L-arabinopyranoside 16-O-[O--L-rhamnopyranoside-(1 6)--D-glucopyranoside], C47-H80O17, mp 194–197°C (methanol); [] D 24 +15.7 ± 2° (c 0.88; pyridine). The enzymatic hydrolysis of (I) has yielded cyclofoetigenin B (III), 24S-cycloartane-3,16,24,25,29-pentaol 16-O--D-glucopyranoside, (IV), C36H62O10, mp 223–225°C (acetone), [] D 24 +37 ± 2° (c 0.97; methanol) and 24S-cycloartane-3,16,24,25,29-pentaol 16-O-[O--L-rhamnopyranosyl-(1 6)--D-glucopyranoside, C42H72O14, mp 229–231°C (methanol), [] D 30 +41 ± 2° (c 0.7; methanol). Details of the IR and1H and13C NMR spectra of the compounds are given.Irkutsk Institute of Organic Chemistry, Academy of Sciences of the USSR. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Trashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 341–345, May–June, 1986.  相似文献   

3.
The asymmetric induction in the synthesis of 3,4,5-trisubstituted 4,5-dihydropyrazoles with ferrocenyl substituents, starting from the E and Z isomers of ,-unsaturated ketones was studied. A high diastereoselectivity was revealed at the 1,2 chiral center chiral center induction, which is independent of the configuration of the starting chalcones.  相似文献   

4.
Résumé Nous avons étudié les complexes que forment les acides éthylèneglycolbis-(-aminoéthyléther)] Sr,N-tétracétique et ,-diaminodiéthylétherN,N-tétracétique, soit avec le thorium, soit avec les terres cériques et, à la suite de cette étude, nous avons pu établir une méthode d'analyse et une séparation du thorium d'avec les terres cériques qui nous a donné satisfaction.
Summary A study has been conducted of the complexes formed by the ethyleneglycol-bis (-amino-ethylether)-N,N-tetraacetic acid and,-diaminodiethylether-N,N-tetraacetic acid with either thorium or the ceric earths. As a result of this investigation, it was possible to set up a method of analysis and a separation of thorium from the cerium earths. These procedures have proved satisfactory.

Zusammenfassung Die von Äthylenglykol-bis-(-aminoäthyläther)-N,N-tetraessigsäure bzw.von ,-Diaminodiäthyläther-N,N-tetraessigsäure mit Thorium bzw. mit den Cer-Erden gebildeten Komplexe wurden untersucht. Auf Grund der Ergebnisse konnte ein Analysenverfahren und eine Trennungsmethode für Thorium und Cer-Erden entwickelt werden.


Une communication de ce travail a été faite à Graz, lors de la commémoration du centenaire de la naissance deF. Emich.  相似文献   

5.
First experiments on the transmutation of long-lived129I and237Np using relativistic protons of 3.7 GeV are described. Relativistic protons generate in extended Pb-targets substancial neutron fluences. These neutrons get moderated in paraffin and are used for transmutation as follows:129I(n,)130I and237Np(n,)238Np. The isotopes130I (T 1/2-12.36 h) and238Np (T 1/2=2.117 d) were identified radiochemically. One can estimate the transmutation cross-section (n,) in the given neutron field as (129I(n,))=(10±2)b and (237Np(n,))=(140±30)b The experiments were carried out in November 1996 at the Synchrophasotron, LHE, Dubna, Russia. The investigation has been performed at the Laboratory of High Energies, JINR, Dubna.  相似文献   

6.
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   

7.
The corresponding 2,3-diphenyl[3,2-a]pyrimidinium salts were obtained by the condensation of 4,5-diphenyl-2-aminothiazole perchlorate with -diketones, -chlorovinyl ketones, -chlorovinyl aldehydes, and 1,1,3,3-tetraethoxypropane. The PMR spectra were used to prove the structures of the compounds obtained, particularly to select the structures of the isomeric salts obtained in the condensation with unsymmetrical -diketones, -chlorovinyl ketones, and -chlorovinyl aldehydes. As a rule, the latter give one isomer — the -unsubstituted (relative to the bridge nitrogen atom) derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 629–631, May, 1972.  相似文献   

8.
Roots of Tragacantha stipulosa Boriss yielded three triterpene glycosides of the cycloartane series: askendoside G (1), askendoside D (2), and cycloglobiceposide B (3). Glycoside 1 is 3-O--L-arabinopyranosyl-(12)--D-xylopyranoside; 16-O--D-glucopyranoside-24R-cycloartan-3,6,16,24,25-pentaol; 2 - 3-O--L-arabinopyranosyl-(12)--D-xylopyranoside; 6-O--D-xylopyranoside-20R,24S-epoxycycloartan-3,6,16,25-tetraol; 3 - 3-O--D-xylopyranoside; 16-O--D-glucopyranoside; 25-O--D-glucopyranoside-24R-cycloartan-3,6,16,24,25-pentaol.  相似文献   

9.
Zusammenfassung An Grundzuständen ,-ungesättigter Carbonylverbindungen sind polare Grenzstrukturen stark beteiligt, vgl. z. B.1011. Die bathochrome Verschiebung der Carbonylabsorption in IR- und der Einfluß auf chemische Verschiebungen und Kopplungskonstanten in NMR-Spektren wird untersucht.
The influence of mesomerism in IR and NMR spectra of ,-unsaturated carbonyl compounds
Polar resonance structures have a great share in the ground level of ,-unsaturated carbonyl compounds, compare1011. The bathochrome displacement of carbonyl absorption in IR spectra and the influence on shift and coupling constants in NMR spectra are investigated.
  相似文献   

10.
Conclusions Syntheses are reported for ,-dithioalkyldivinyl ketones, which react with ammonia to give -amino--thioalkyldivinyl ketones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2414–2415, October, 1988.The authors thank A. M. Kachurin for assistance in taking the spectra.  相似文献   

11.
Two novel glycosides from the starfishSolaster dawsoni (Verrill) have been isolated and characterized: 24-O-(-D-xylopyranosyl)-5-cholestane-3,6,15,24,26-pentaol (solasteroside S1) and (24R)-29-O-[-D-galactofuranosyl-(16)--D-galactofuranosyl]-24-ethyl-5-cholestane-3, 6,8,15,16,29-hexaol (solasteroside S2).Translated fromIzvestiya Akademu Nauk. Seriya Khimicheskaya, No. 5, pp. 980–982, May, 1993.  相似文献   

12.
Six polyhydroxylated steroids and their derivatives were isolated from the starfish Lysastrosoma anthosticta collected in the Posyet Bay, Sea of Japan. These include a new glycoside of the steroid polyol, lysastroside A (1), which was identified as (25S)-26-O--d-xylopyranosyl-5-cholestane-3,6,8,15,16,26-hexaol, and the previously known pycnopodioside C monoglycoside (2), marthasterone sulfate (3), (25S)-5-cholestane-3,6,8,15,16,26-hexaol (4), (25S)-5-cholestane-3,6,7,8,15,16,26-heptaol (5), and (25S)-5-cholestane-3,6,7,8,15,16,26-heptaol (6). The compounds were tested for the haemolytic activity and the action on the embryogenesis of the sea urchin Strongylocentrotus intermedius.  相似文献   

13.
The new cycloartane glycoside cyclogaleginoside E, 20S,24R-cycloartan-3,6,16,25-tetraol-3-O--D-xylopyranoside-25-O--D-glucopyranoside, was isolated from stems of Astragalus galegiformis L. Its structure was established using enzymatic and total acid hydrolysis, mass spectrometry, and PMR and 13C NMR.  相似文献   

14.
Summary The reaction of the 3-acetate of the 20-ketal of 16,17-oxido-5-pregnenol-3-one-20 with methylmagnesium iodide and subsequent hydrolysis of the reaction product yielded 16-methyl-5-pregnenediol-3 –17-one –20. 18-Nor-17-methyl-17-iso-5.11-pregnadienediol-3,16-one-20 was formed as a by-product.  相似文献   

15.
Irradiation of 5-benzyl-, 5-methoxymethyl-, and 5-allyl-substituted codeinones and morphinones with UV light ( 366 nm) leads to formation of the corresponding 18-phenyl, 18-methoxy, and 18-vinyl derivatives of 4,5-epoxymethanomorphin-7-en-6-one.  相似文献   

16.
The oxime of 5-pregnen-3-ol-20-one reacts with acetylene in the KOH-DMSO system to form a mixture of products containing 3-vinyloxy-17-(1-vinyl-2-pyrrolyl)-5-androstene as the major product (63% yield) and also the O-vinyloxime of 3-vinyloxy-5-pregnen-20-one (10%), 3-vinyloxy-17- and 3-vinyloxy-17-5-pregnen-20-one (25%, 1:4 ratio).  相似文献   

17.
60Co -ray radiolysis of cholesterol /3-hydroxy-5-cholestene/ /I/ in the two-phase system /water-ethyl acetate/ and in the presence of air has been studied using TLC and GC methods. The following products were observed in the irradiated mixture: 3, 7-dihydroxy-5-cholestene /II/, G O. 36, 3-hydroxy-7-keto-5-cholestene /III/, G 1.48, 3-hydroxy-7-keto-5-cholestane /IV/, G 0.22, 3,5,6-trihydroxy-5-cholestane /V/, G 0.83, 5,6-epoxy-3-hydroxy-5-cholestane /VIa/, G 0.26, 5,6-epoxy-3-hydroxy-5-cholestane /VIb/, G 0.24, and 2, 3-dihydroxy-5-cholestene /VII/, G 0.22. The dose dependence of the formation of these products shows that the cholesterol derivatives substituted in the position 7 /II–IV/ are formed from a common precursor — the radical Ia. On the other hand, the products of the 5–C=C double bond reactions /V and VI/ are formed independently. Also the product VII is formed independently. A reaction scheme that is in agreement with these results is proposed.  相似文献   

18.
Zusammenfassung Bei der Umsetzung von Vinylphenylketonen mit Harnstoffen oder Thioharnstoffen entstehen 2-Oxo- bzw. 2-Thionotetrahydropyrimidine und 2-Oxo- bzw. 2-Thiono-5-(-benzoyläthyl)-6-phenyltetrahydropyrimidine; -Benzoyläthyldimethylamin und analoge Basen geben mit Thioharnstoffen nur 5--Benzoyläthylderivate. 2-Oxo- und 2-Thiono-6-phenyltetrahydropyrimidine sind in der Kernstelle 5 alkylierbar brw. aminoalkylierbar.
Vinyl phenyl ketones react with ureas or thioureas to 2-oxo-or 2-thionotetrahydropyrimidines and 2-oxo- or 2-thiono-5-(-benzoylethyl)-6-phenyltetrahydropyrimidines; -benzoylethyldimethylamines and analogous compounds give with thiocarbamides 5--benzoylethyl derivates. 2-oxo- and 2-thiono-6-phenyltetrahydropyrimidines react with 1-phenyl-2-propene-1-ones, -benzoylethylamines resp. formaldehyde and amines to 5-alkyl products.
  相似文献   

19.
Summary The addition reaction of esters of nitroacetic acid to, -unsaturated ketones was studied, and new esters of ketonitroacids were prepared.  相似文献   

20.
Summary A method for semiquantitative determination of aromatic and,-unsaturated aldehydes such as salicylaldehyde, anisaldehyde, vanillin, veratraldehyde, piperonal, cinnamaldehyde, furfural andp-dimethylaminobenzaldehyde by making circular spots of their isonicotinoyl hydrazones on chromatoplates with circular thin-layer Chromatographic apparatus and their comparison with sensitivity standards has been described. The accuracy is ± 5% and the method is rapid, simple and economical.
Zusammenfassung Ein Verfahren zur semiquantitativen Bestimmung aromatischer und,-ungesättigter Aldehyde wie Salioylaldehyd, Anisaldehyd, Vanillin, Veratrumaldehyd, Piperonal, Zimtaldehyd, Furfural und p-Dimethylaminobenzaldehyd durch Dünnschicht-Ringchromatographie ihrer Isonikotinsäurehydrazone und Vergleich mit Standardchromatogrammen wurde beschrieben. Die Genauigkeit beträgt ±5%.
  相似文献   

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