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1.
A new alkaloid, severidinine, with mp 145–147°C []D –50.2°, C19H45NO6, has been isolated from the epigeal part ofKoralkowia sewerzowii Regel. On the basis of the IR, PMR, and mass spectra of severidinine and its transformation products, and also passage to the known alkaloids severidine, the structure of 3-acetylseveridine has been established for severidinine.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 488–490, July–August, 1983.  相似文献   

2.
Summary From the roots ofFerula teterrima Kar. et Kir. a new terpenoid coumarin — feterin — has been isolated with the formula C26H32O6, mp 155–158°C, [] D -52.02° (chloroform), M+ 440, the structure and relative configuration of which have been established with the aid of the INDOR method and on the basis of a study of the PMR spectra in the presence of the paramagnetic shift reagent Eu(DMP)3.All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 318–322, May–June, 1978.  相似文献   

3.
A new steroid glycoside — alliospiroside B (I) — has been isolated from the collective fruit ofAllium cepa L. On the basis of chemical transformations and with the aid of physicochemical measurements it has been established that compound (I) has the structure of (25S)spirost-5-ene-1,3-diol 1-O-[O--L-rhamnopyranosyl-(1 2)--D-galactopyranoside. Compound (I) C39H62O3, mp 200–202°C (from ethanol). [] D 20 –110.9±2° (c 1.01; pyridine) was obtained by extracting the collective fruit ofA. cepa with ethanol folowed by the column chromatographic separation of the combined glycosides on silica gel. The acid hydrolysis of (I) gave (25S)-ruscogenin (II), C27H42O4, mp 189–191°C, [] D 23 –104.1±2° (c 0.98; pyridine). The1H and13C NMR spectra are given for both compounds and the IR spectrum for compound (I).Institute of the Chemistry of Plant Substances of the Uzbek SSR, Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 589–592, September–October, 1986.  相似文献   

4.
    
The new diguaianolide anabsin, C30H40O7, mp 276°C (decomp.), []25 +110° (c 1.7; acetone) has been isolated fromArtemisia absinthium L. Anabsin acetate, dehydroanabsin, and dehydroanabsin acetate have been obtained. A comparative study of the1H and13C NMR spectra of anabsin, absinthin, and anabsinthin has been made. The structure of anabsin has been established and structures have been suggested for absinthin and anabsinthin. The most probable biogenesis of anabsin in plants has been put forward.Delivered at the Eleventh International Symposium on the Chemistry of Natural Compounds, Bulgaria, September, 1978 [7].Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 495–501, July–August, 1979.  相似文献   

5.
Summary A new alkaloid, C15H22ON2, with mp 84–85°C [] D 20 + 77.9° (c 0.56; ethanol) has been isolated fromSophora alopecuroides L. On the basis of UV, IR, PMR, and mass spectral characteristics and the hydrogenation reaction, its most probable structure has been determined as 13,14-dehydrosophoridine.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 231–233, March–April, 1978.  相似文献   

6.
FromFumaria vaillantii, collected in the Tashkent province, 18 alkaloids have been isolated of which N-methyladlumine with mp 198–199°C, []D-45° (c 0.5; methanol) has proved to be new. Its structure has been established on the basis of spectral characteristics and a direct comparison withl-adlumine methiodide.Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 602–604, September–October, 1981.  相似文献   

7.
From the roots and epigeal parts ofHaplophyllum dauricum (L.) G. Don., new acylated courmarin glycosides have been isolated: dauroside A, C23H28O13, mp 145–147°C (ethanol), [] D 22 – 72.7° (methanol), and dauroside B, C30H32O14, mp 145–150°C (methanol) [] D 22 0° (pyridine). Their structures have been established on the basis of chemical transformations and IR, UV, mass,1H NMR and13C NMR spectra.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 142–147, March–April, 1983.  相似文献   

8.
Densities and apparent molar volumes of aqueous 2-chloroethanol were determined at temperatures from 15.0 to 34.4°C using digital densimetry. The results of the volumetric measurements have been used to calculate the following thermodynamic quantites at 25°C: V 2 o = 55.05 ± 0.02 cm3-mol–1, (V 2 o/T)p = 0.01486 ± 0.00318 cm3-K–1-mol–1, and (2 V 2 o/T 2)p = 0.02972 ± 0.00318 cm3-K–2-mol–1. Partial molar volumes of transfer from water to 1 mol-dm–3 2-chloroethanol have also been determined for L-glycine, L-alanine, L-serine, L-glutamic acid, and L-aspartic acid at 35.0°C. The transfer results have been explained in terms of the nature of the interactions of the groups in the solute and solvent. Hydration numbers of L-glycine and L-alanine have also been calculated in aqueous 2-chloroethanol.  相似文献   

9.
Summary A new hasubanan alkaloid with the composition C29H33O9N, mp 128–129°C9 from ether), [] D 20 – 25° (c 2; ethanol) containing an ester group has been isolated from the herbStephania hernandifolia and has been called hernandifoline.All-Union Scientific-Research Institute for Medicinal Plants. Translated from Khimiya Prirodynkh Soedinenii, No. 2, pp. 158–164, March, 1971.  相似文献   

10.
A new steroid saponin has been isolated from the air-dry leaves ofYucca aloifolia L., and it has been shown to be (25R)-5-spirostan-3-ol O-D-glucopyranosyl-(1 2)-D-galactopyranoside. The substance melts at 302–303°C []D20 –27.2, (c 1.0; CHCl3).I. G. Kutateladze Institute of Pharmacochemistry, Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Khimiya Prirodnikh Soedinenii, No. 6, pp. 744–747, November–December, 1984.  相似文献   

11.
The ionization constant of ammonia has been determined by conductivity measurements and found to vary from 1.77×10–5 at 25°C to 1.3×10–6mol-kg–1 at 250°C. The pressure effect to 2000 bar has been measured and the ratio K2000/K1 is 6.8 at 25°C and 11 at 250°C. The standard molar volume change for the ionization at 1 bar, V 1 o , changes from –28.8 at 25°C to –67 cm3-mol–1 at 250°C.  相似文献   

12.
Summary A new base with the composition C21H25O5N, mp 192–194°C, []D -182°C, which has been called collutine, has been isolated from the epigeal parts ofColchicum luteum Baker.On the basis of UV, IR, NMR, and mass spectra and chemical reactions, the structure of 4-hydroxy-2,3, 6-trimethoxyhomomorphinandienone has been proposed for collutine.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 758–761, November–December, 1975.  相似文献   

13.
Using a hydrogen-electrode thermocell with a temperature difference of 8 K, initialthermoelectric power in has been determined in aqueous tetra-n-butylammoniumhydroxide solutions for concentrations ranging from 0.001 to 0.2 molal at meantemperatures of 25 and 35°C. Graphs of a function of in vs. m 1/2/(1 + m 1/2) yieldintercepts and infinite-dilution limiting slopes as m 1/2 0. Using the value = 68.8±0.3 J-K–1for the standard transported entropy of the hydroxideion, values for the enthalpy of transport of tetra-n-butylammonium hydroxide atinfinite dilution were determined to be 36.5±1.5 kJ-mol–1 at25° and 37.7±2.0kJ-mol–1 at 35°C.  相似文献   

14.
From the roots with rhizomes of the plantRhaponticum carthamoides Willd) Iljin Compositae), in addition to integristerone A, ecdysterone, polypodin B, 2-deoxyecdysterone, and 24(28)-dehydromakisterone A, we have isolated the new compounds ecdysteron3–2,3-monoacetonide (I), ecdysterone 20,22-monoacetonide (II)) and rhapisterone (III): I — C30H48O7, mp 232–233° (ethyl acetate-methanol) [] D 20 +56.4±2° (c 0.0; methanol); II — C30H48O7, mp 227–229° (ethyl acetate-methanol), [] D 20 +60.1±2° (c 1.3; methanol); III — C29H48O7, mp, 241–242° (ethyl acetate-methanol), [] D 20 +30±2° (c 0.1; dioxane). The structure of (III) was established on the basis of spectral characteristics as 2, 3, 14, 20R, 22R, 23-5-stigmast-7-en-6-one. Details of the PMR, mass, and IR spectra of all the compounds and of the CD of rhapisterone are given.Institute of the Chemistry of Plant Substances of the Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 681–684, September–October, 1987.  相似文献   

15.
The sublimation pressure of chromium trichloride was measured by the static method with a quartz membrane-gauge manometer in the temperature range of 875–1230 K. An approximating equation for the sublimation pressure vs. temperature was found. The enthalpy (259.4±4 kJ mol–1) and the entropy (224.2±3.5 J mol–1 K–1) of sublimation at 298 K were calculated. For the process 2 CrCl3(g) + Cl2(g) = 2 CrCl4(g), the following values were obtained: r H°298 = –207.1±11.6 kJ mol–1 and r S°298 = –173.6±10 5 J mol–1 K–1.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1561–1564, August, 2004.  相似文献   

16.
By column chromatography on polyamide sorbent, the inflorescences of pot marigold calendula have yielded eight substances of flavonoid nature: two aglycons — quercetin (C15H10O7, mp 309–311°C) and isorhamnetin (C16H12O7, mp 314–316°C); six glycosides, of which three have been identified as isoquercetin (C21H20O12, [] D 20 –36° in methanol, mp 218–220°C), isorhamnetin 3-O--D-glucoside (C22H22O12, [] D 20 –59° in dimethylformamide, mp 193–195°C), narcissin (C28H32O16, [] D 21 –28° in dimethylformamide, mp 180–182°C), and three substances that have proved to be new and have been called calendoflaside (C28H32O15, [] D 21 –85° in methanol, mp 192–195°C; calendoflavoside (C28H32O16, [] D 20 –106° in methanol, mp 189–192°C), and calendoflavobioside (c27H30O16, [] D 20 –105° in methanol, mp 194–197°C).All-Union Scientific-Research Institute of Drug Chemistry, Khar'kov. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 795–801, November–December, 1988.  相似文献   

17.
Summary The roots ofInula grandis Schrenk has yielded a sesquiterpene lactone C15H20O3, mp 134–135°C and 270°C, which has been called igalin, and two diols — C15H26O2 with mp 102–102.5°C and C15H28O5 with mp 320°C — which have been called igalol and grandol, respectively.Igalol is identical with the diol obtained by the reduction of igalan with sodium borohydride, and has the structure elemane-8,12-diol.The sesquiterpene hydroxy lactone lactone No. 8 has been isolated in the form of an oil and it is now being studied.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 17–20, January, 1971.  相似文献   

18.
Conductances of sodium bromide, iodide, and perchlorate, potassium chloride, and tetraphenylboride (BPh 4 ) as well as triisoamyl-n-butylammonium iodide (i-Am3BuNI) have been measured in aqueous mixtures containing up to 20 mole percent dimethylsulfoxide (DMSO) at 25°C. Experimental data were analyzed by the 1965 Fuoss-Onsager-Skinner (FOS) equation. Single-ion limiting equivalent conductances were calculated by assuming that 0 (i–Am 3 BuN +=0 (BPh 4 ). The variations of the limiting ionic Walden products are discussed on the basis of acid-base type interactions for cations, and on the basis of structural effects for anions.  相似文献   

19.
Summary The reaction between the title compound, ,,,-tetra(p-sulphonatophenyl)porphynatoaquacarbonylruthenate(II), [Ru(TPPS)(CO)(H2O)]4–, and CN- revealed that only the aqua ligand is substituted even in the presence of a large excess of the nucleophile. The pK a1 was spectrophotometrically determined as 13.4(5) (at 33.2 °C) and kinetically as 13.44(5) (at 33.6 °C). The rate of aqua substitution was determined as 89(4)m –1 s –1 at 35.1 °C and the activation enthalpy and entropy as 55.44(1) kJ mol–1 and-27.90(4) J K–1 mol–1, respectively.  相似文献   

20.
The kinetics of base hydrolysis of the trans-[Cr(NH3)2(NCS)4] anion follows the rate law: -d[complex]/dt = k 0 + k 1[OH] (50–70 °C, [OH] = 0.1–1.9 M and = 2.0 M). The specific salt effect has been investigated for eight aqueous media: NaCl, NaBr, NaI, NaClO4, KCl, KBr, CsCl and CsBr. The alkali-independent path (k 0) does not show any specific effect of inert electrolyte ions, the activation parameters: H = 113.5 ± 0.4 kJ mol–1 and S = 24.1 ± 1.3 J mol–1 K–1 are interpreted in the frame of a dissociative interchange mechanism (I d). For the alkali-dependent path (k 1) the specific salt effect is observed for cations of the inert electrolyte, showing an important role for ion-pair formation between the cations and reagent complex anion in the activation process. A linear correlation between lnk 1 and lnK 0 (K 0 – ion-pair formation constant) has been found for the cations studied. The dissociative, via conjugate base, mechanism (D CB) has been proposed for the alkali-dependent path.  相似文献   

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