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1.
Results are given which confirm the structure of the furostanol glycoside from tomato seeds forming wastes of the preserving industry. From a butanolic extract of the seeds ofLycopersicum esculentum Mill. we have isolated the furostanol glycoside tomatoside A (I) the structure of which has been established as 25(S)-5-furostan-3,22,26-triol 26-O--D-glucopyranoside 3-O-[O--D-glucopyranosyl-(12)-O--D-glucopyranosyl-(14)--D-galactopyranoside]. At the same time, by enzymatic and chemical transformations three new spirostanol glycosides of neotigogenin have been obtained: tomatoside B (III), which is 25(S)-5-spirostan-3-ol 3-O-[O--D-glucopyranosyl-(12)--D-galactopyranoside], 25(S)-5-spirostan-3-ol 3-O-[O--D-glucopyranosyl-(14)--D-galactopyranoside] (V), and 25(S)-5-spirostan-3-ol 3-O--D-galactopyranoside (IV).Institute of Organic Chemistry, Academy of Sciences of the Kirghiz SSR, Frunze. Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 533–540, July–August, 1980.  相似文献   

2.
In this work the potential of MIMS (Membrane Introduction Mass Spectrometry) for studying the inclusion of small organic guest molecules into cyclodextrin hosts in aqueous medium was investigated. MIMS profiles showed that the inclusion of benzene in cyclodextrins is favored in the following order: -CD HO-propyl--CD> -CD> -CD with equilibrium constants of K -CD = 404; KHO-propyl-CD = 395, K -CD = 335 and K -CD = 210 M-1 at 25 °C. Kinetic experiments suggested that under the conditions employed the inclusion process has a pseudo first-order dependence on the guest benzene concentration with the following order: -CD > -CD HO-propyl--CD> -CD. MIMS inclusion profiles of chlorobenzene and toluene showed that the presence of substituents in benzene makes the inclusion in -CD more difficult. Experiments with ferrocene--CD have also been carried out, showing that the complex rapidly dissociates in water and the resulting free -CD can complex with benzene present in the solution.  相似文献   

3.
The known triterpene glycosides hederagenin 3-O--L-arabinopyranoside, hederagenin 3-O-\-D-glucopyranoside, oleanolic acid 3-O--sophoroside, hederagenin 3-O--sophoroside, and their 28-O--gentiobiosyl esters, respectively, in addition to the new triterpene glycoside 3-O--sophorosyl-28-O--L-rhamnopyranosyl-(14)-O--gentiobiosyl hederagenin are isolated fromFatsia japonica (Araliaceae) seeds. The structures of these glycosides are established using chemical and spectral methods.Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 131–133, March–April, 2000.  相似文献   

4.
Inclusion complexation of all-trans-retinol, retinal and retinoic acid with -cyclodextrin (-CD) and heptakis(2,6-O-dimethyl)--cyclodextrin (DM--CD) were investigated by means of UV-vis spectroscopy. The association constants (K a) obtained for vitamin A with DM--CD is greater than with -CD. On the other hand, for the same host compoundK a values of retinol, retinal and retinoic acid are very close to each other.  相似文献   

5.
Summary Steroid glycosides of the cardenolide group have been found inOrnithogalum magnum.Three glycosides, provisionally called substances a, b, and c, have been isolated by adsorption chromatography on alumina.Substance a is 3-(O--L-rhamnopyranosyl)-11, 14-dihydroxy-5-card-20(22)-enolide (rohdexin A).Khimiya Prirodnykh Soedinenii, Vol. 1, No. 3, pp. 156–160, 1965  相似文献   

6.
Summary The dichloride of -ethoxyvinyl-, -isooctyloxyvinyl-, and 2-chloro-3-methylbut-3-enylphosphonous acids have been synthesized and characterized for the first time. The diethyl ester of -ethoxyvinylphosphonous acid has been-obtained from the dichloride of -ethoxyvinylphosphonous acid.  相似文献   

7.
Summary New flavonoid glycosides have been obtained from the roots ofRhodiola algida: rhodalgin (I), composition C20H18O11, mp 239–240°C; acetylrhodalgin (II) C22H20O12, mp 223–224°C; diacetylrhodalgin (III), C24H22O13, mp 208–209°C; and triacetylrhodalgin (IV), C26H24O14, mp 230–231°C.It has been established that they have the following structures: (I), 3,4,5,7,8-pentahydroxyflavone 8-O--L-arabinopyranoside; (II), 3,4,5,7,8-pentahydroxyflavone 8-O-(3-O-acetyl--L-arabinopyranoside; (III), 3,4,5,7,8-pentahydroxyflavone 8-O-(2,3-di-O-acetyl)--D-xylopyranoside; and (IV), 3,4,5,7,8-pentahydroxyflavone 8-O-(2,34-tri-O-acetyl)--D-xylopyranoside. The -L-arabinopyranose and -D-xylopyranose are present in these compounds in the C1 conformations.In the performance of this investigation, the authors consulted O. S. Chizhov, and M. B. Zoltarev (N. D. Zelinskii Institute of Organic Chemistry of the Academy of Sciences of the USSR) and V. I. Sheichenko (All-Union Institute of Medicinal plants).All-Union Scientific-Research Institute of Medicinal Plants. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 712–720. November–December, 1975.  相似文献   

8.
Two new glycosides of the cholestane series (allosides A and B) have been isolated from the fruit of the cocultivatedAllium suvorovii Rgi. andAllium stipitatum Rgl. (family Liliaceae, local name anzur). The acid hydrolysis of both compounds gave a sterol not previously described, which has been called alliosterol and has the structure of (22S)-cholest-5-ene-1, 3, 16, 22-tetraol, and the product of its dehvdration, which is (16S, 22S)-furost-5-ene-1, 3-diol. Alloside A is the 16-O--D-galactopyranoside, and alloside B the 16-O--D-galactopyranoside 1-O--D-glucopyranoside of alliosterol.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 231–241, March–April, 1991.  相似文献   

9.
Summary 1. The synthesis of the following neutral plasmalogens has been effected: -O-(octadec-1-enyl)-, distearoylglycerol, -O-(octadec-1-enyl)-, -dipalmitoylglycerol, -O-(hexadec-1-enyl)-, -distearoylglycerol, and -O-(pentadec-1-enyl)-, -dipalmitoylglycerol.2. During the synthesis, the following compounds were isolated and characterized by their physicochemical constants: the -octadec-1-enyl ether of glycerol, -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, the tosylate of -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, and -O-(2-tosyloxyoctadecyl) glycerol.3. The IR spectra of the -octadec-1-enyl ether of glycerol and the neutral plasmalogens have been studied.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 367–371, 1966  相似文献   

10.
Summary Four substances have been isolated from the seeds ofCoronilla hyrcana: hyrcanoside, deglucohyrcanoside, hyrcanogenin, and substance E.It has been established that hyrcanoside (I) has the structure 3-(O--D-xylopyranosyl- <4 1 > -O--D-glycopyranosyl)-14-hydroxy-19-oxocard-4, 20 (22)-dienolide; deglucohyrcanoside (VII) is 3-(O--D-xylopyranosyl)-14-hydroxy-19-oxocard-4, 20 (22)-dienolide; and hyrcanogenin (V) is 3, 14-dihydroxy-19-oxocard-4, 20 (22)-dienolide. Both the aglycone hycanogenin (V) and its glycosides (I) and (VII) are new compounds.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 4, pp. 251–257, 1966  相似文献   

11.
Aim of the present work was to investigate the effect of somecyclodextrins (CDs) on the solubility and ocular bioavailability of rufloxacin base (RUF), with theultimate goal of developing an ophthalmic formulation. Phase solubility studies of RUF inpH 7.4 buffer were carried out in the presence of -cyclodextrin (-CD),hydroxypropyl--cyclodextrin (HP--CD) and -cyclodextrin(-CD). The effect of hydroxypropyl methylcellulose (HPMC) on RUF solubility was evaluated after heating the solutionscontaining HP--CD at 120 °C.A significant enhancement of RUF solubility was achieved by associatingthe drug with CDs, particularly HP--CD. This CD formed with RUF a less stablecomplex than that formed by -CD, but did not suffer the solubility limitations ofthe parent CD, and showed a higher solubilizing capacity than -CD. Addition of 0.25%(w/v) HPMC to solutions containing HP--CD increased the solubilizing effect of this CD,thus allowing reduction of the amount necessary for solubilization of 0.3% (w/v) RUF.Preliminary pharmacokinetic data in rabbits indicated that theocular bioavailability of 0.3% (w/v) RUF solubilized by HP--CD was higher when compared witha 0.3% (w/v) RUF suspension used as reference.  相似文献   

12.
Two new glycosides which have been called nolinofurosides G(I) and H(III), have been isolated from the leaves ofNolina microcarpa. Nolinofuroside G is the sodium salt of 26--D-glucofuranosyloxy-(25S)-furost-5,20(22)-diene-1, 3-diol 1-sulfate, and nolinofuroside H is the sodium salt of 1--D-fucopyranosyloxy-26--D-glucopyranosyloxy-(25S)-furost-5,20(22)-dinen-1-3-ol 3-sulfate.M. V. Frunze Simferopol' State University. Institute of the Chemistry of Plant Substances, Uzbek. Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 801–806, November–December, 1991.  相似文献   

13.
The solubility of nimodipine was measured in aqueous solutions of the following cyclodextrins: -cyclodextrin (-CD), hydroxypropyl--CD (HP--CD), -cyclodextrin (-CD), random substituted methyl--CD (M--CD), three hydroxypropyl--CDs (HP--CD) with mutually different average degree of substitution, and hydroxypropyl--cyclodextrin (HP--CD). From the determined linear solubility diagrams the values of the binding constant K11 of the inclusion complexes of nimodipine with the respective CDs were evaluated. The -CDs efficiently solubilized sparingly soluble nimodipine, the highest value of K11 was found for M--CD (1680 M-1), followed by -CD (550 M-1) and HP--CDs, where the higher degree of substitution lowered K11. Only slight solubilization of nimodipine was observed in the solutions of the -CDs and HP--CD.  相似文献   

14.
Zusammenfassung Primäre und sekundäre Enaminderivate, die aus -Ketoestern und -Diketonen darstellbar sind, reagieren mit Malonylchloriden bzw. Malonsäuren in Acetanhydrid zu 4-Hydroxypyridonen.
Primary and secondary enamines readily obtained from -ketoesters and -diketones react with malonyl chlorides or malonic acids in acetic anhydride to yield derivatives of 4-hydroxy-2-pyridone.
  相似文献   

15.
Condensation of (±)-5-allyl-2,3,5-trichloro-4,4-dimethoxy-2-cyclopentenone with phenylethynylmagnesium bromide in THF gave (±)-5-allyl-2,3,5-trichloro-4,4-dimethoxy-1-phenylethynyl-2-cyclopenten-1-ol which chemoselectively reacted with ozone at the terminal double bond, affording (±)-2,3,5-trichloro-5-formylmethyl-4,4-dimethoxy-1-phenylethynyl-2-cyclopenten-1-ol. Oxidation of the latter with H2CrO4 yielded a mixture of the expected product, (±)-5-carboxymethyl-2,3,5-trichloro-4,4-dimethoxy-1-phenylethynyl-2-cyclopenten-1-ol, and anomalous profound oxidation product, (±)-2,3,5-trichloro-5-carboxymethyl-4,4-dimethoxy-1-(2-oxo-2-phenylacetyl)-2-cyclopenten-1-ol. Attempts to remove protective methoxy groups in these compounds under standard conditions were unsuccessful.  相似文献   

16.
From an ethanolic extract of the holothuriansStichopus chloronotus by column chromatography on silica gel a new triterpene oligoside has been isolated the structure of which has been established as 23(S)-acetoxy-3-{4-O-[O-(3-O-methyl--D-glucopyranosyl)-(13)--D-glucopyranosyl]-2-O-[O-(3-O-methyl--D-glucopyranosyl(-(13)-O--D-xylopyranosyl-(14)--D-glucopyranosyl]--D-xylopyranosyloxy}holost-7-ene. A hypothesis has been put forward concerning the biosynthesis of the carbohydrate chains in the glycosides of holothurians of the orderAspidochirota from bioside blocks.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 200–204, March–April, 1982.  相似文献   

17.
From the stems of Crimean ivyHedera taurica Carr. (fam. Araliaceae) we have isolated the new triterpene glycosides St-I3, St-I5, and St-I4a, which are, respectively, the 3–0--D-glucopyranoside 28-O-[O--L-rhamnopyranosyl-(14)-O-(6-O-acetyl--D-glucopyranosyl)-(16)-O--D-glucopyranosides] of oleanolic acid and of hederagenin and the 3-O--D-glucopyranuronoside 28-O--gentiobioside of oleanolic acid, and also the previously known 3-O-[O--D-galactopyranosyl-(12)--D-glucopyranuronoside 28-O--D-glucopyranoside] of oleanolic acid (glycoside Rb-4).Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 404–410, May–June, 1997.  相似文献   

18.
We measure the cis and trans constants3JCO, H and we discuss the effect on them from the structural factors in the13C spectra of 76 conjugated -amino, alkoxy-, alkyl-, dialkyl-, phenyl--carbonyl-, and ,-dicarbonyl-containing compounds. We show that the3JCO, H are stereospecific [3JCO, H (cis) (trans)] in all the studied compounds. On the basis of the stereo-specificity of the constants, we determine the configuration of the trisubstituted , double bond in ketones, ketoesters, and imides of different structures.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 356–365, February, 1990.  相似文献   

19.
Two new glycosides have been isolated from the total triterpene glycosides of the holothurianDuasmodactyla kurilensis: kurilosides A (III) and C (IV). It has been established that (III) is 16-acetoxy-3-{[O--D-glucopyranosyl-(1 4)-O--D-quinovopyranosyl-(1 2)]-[O-(3-O-methyl--D-glucopyranosyl)-(1 3)-O-(6-O-(sodium sulfato)--D-glucopyranosyl)-(1 4)]--D-xylopyranosyloxy}-4,4,14-trimethylpregen-9(11)-en-20-one, while the minor glycoside (IV) is 16-acetoxy-3-{O--D-quinovopyranosyl-(1 2)-[O-(3-O-methyl--D-glucopyranosyl-(1 3)-O-(6-O-(sodium sulfato)--D-glucopyranosyl)-(1 4)]--D-xylopyranosyloxy}-4,4,14-trimethylpregn-9(11)-en-20-one.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–226, March–April, 1991.  相似文献   

20.
The interactions of nabumetone (NAB) with -cyclodextrin (-CD) and-cyclodextrin (-CD) were studied in aqueous solution by meansof phase-solubility analysis. Solid dispersions of NAB with -cyclodextrin(-CD), -cyclodextrin (-CD), methyl- (M-CD),hydroxypropyl-cyclodextrin (HP-CD) were prepared by coevaporationand kneading and also by coprecipitation in the case of -CD. X-ray diffractometry, thermal analysis and infrared spectroscopy (FTIR) were used to study the possibility of complexation of the drug with the different cyclodextrins. Solid dispersions of nabumetone with -CD showed a remarkable improvement in the dissolution rate of nabumetone.  相似文献   

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