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1.
-Cyclodextrin having cinnamamide at 6- or 3-positions (6-CiNH--CD, 3-CiNH--CD) and -cyclodextrin with cinnamamide on 6-position (6-CiNH--CD) have been prepared. Supramolecular structures were formed in the solid state or aqueous solutions and characterized by measurements of NMR and vapor pressure osmometry (VPO). The results indicate that 6-CiNH--CD formed insoluble supramolecular polymers in the solid state, while 6-CiNH--CD and 3-CiNH--CD formed supramolecular complexes in aqueous solutions. 6-CiNH--CD was found to form a dimer in an aqueous solution. 3-CiNH--CD formed intermolecular complexes to give supramolecular polymers. The differences of the position of guest part on cyclodextrins caused to give a variety of supramolecular structures in aqueous solutions.  相似文献   

2.
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   

3.
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   

4.
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   

5.
Summary 1. The reduction of 3-methoxy-D-homoestra-1, 3, 5(10), 8-tetraen-17a-ol (IV) with alkali metals in the presence of ammonium chloride or alcohol gives, in addition to 8, 9-dihydro derivatives, the 8, 9 and 8, 9-epimers, the structure of which has been shown partly by independent synthesis and partly on the basis of chemical reactions and NMR spectra.2. Hydrolysis of the reduction products has given 19-nor-D-homotestosterone (III) and its 8- and 9, 10-epimers (V) and (VI). The ketols (III) and (V) readily form hydroperoxides in air.3. The reduction of the ethylene ketal of 3-methoxy-D-homoestra-1, 3, 5(10), 8-tetraen-17a-one (XIX) takes place stereodirectively and gives only 8, 9-dihydro derivatives.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 2, pp. 90–100, 1965  相似文献   

6.
The leaves of common ivy have yielded 11 triterpene glycosides: the 3-O--L-pyranosides of oleanolic acid (1), of echinocystic acid (2), and of hederagenin; the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside]s of oleanolic acid (4), of echinocystic acid (5), and of hederagenin (6); the O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ester of hederagenin 3-O--L-pyranoside (7); the O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ester of hederagenin 3-O-[O--L-pyranosyl-(12)--L-arabinopyranoside] (9); and the O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl esters of oleanolic acid, echinocystic acid, and hederagenin 3-O-[O--L-rhamnopyranosyl-(12)--D-glucopyranoside]s (8), (10), and (11), respectively. This is the first time that compounds (1), (2), (5), (7), (9), and (10) have been found in this plant.Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 742–746, November–December, 1994.  相似文献   

7.
Heat capacities of anhydrous -and -cyclodextrin were measured by adiabaticcalorimetry between 10 K and 300 K. The thermalbehaviour of the two compounds exhibits significantdifferences. -Cyclodextrin shows an anomalousexcess heat capacity in the entire region between 70 Kand 210 K. In the case of -cyclodextrin, anendothermic effect is observed at 240K. This effect isanalysed through the study of the correspondingentropy change and discussed in terms ofintramolecular organization.Using the known heat capacity values of anhydrous-CD, a comparative analysis has been developed.For each cyclodextrin, the average behaviour of abound -D-glucopyranose has been calculated andcompared. From a thermodynamic point of view, thedegree of organization of the dehydrated macrocycliccompounds could be expressed as-CD -CD -CD.  相似文献   

8.
The interactions between cyclodextrins and tetrahydroharmane, 1-methyl-1,2,3,4-tetrahydro-9H-pyrido/3,4-b/indole, have been investigated in pH 10.1 aqueous media. Absorption and fluorescence studies, together with lifetime measurements show that tetrahydroharmane forms ground state inclusion complexes with -CD and -CD but not with -CD. Steady state experiments detect only one kind of tetrahydroharmane--CD complex, whereas time resolved measurements reveal the existence of two different types of 1:1 association complexes. The results in -CD are very similar to those in -CD, but the interactions are much weaker.  相似文献   

9.
The pseudoguaianolide inuchinenolide C and the eudesmanolide pulchellin C have been isolated for the first time from the flower heads and leaves ofInula caspica Blume, and their spatial structures have been established by an x-ray structural experiment as 2,6-diacetoxy-6-hydroxy-1,7(H),8,10(H)-pseudoguai-11(13)-en-8,12-olide and 2,3-dihydroxy-5,7,8(H)-eudesma-4(15),11(13)-dien-8,12-olide, respectively.Institute of Organic Synthesis and Coal Chemistry, Academy of Sciences of the Kazakh SSR, Karaganda. A. N. Nesmeyanov Institute of Organometallic Compounds, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 748–757, November–December, 1990.  相似文献   

10.
3-Chloro-5,7-dibromo-6-ketosteroids 5a and 5b are synthesized from -sitosterol (1a) and cholesterol (1b). Dehydrohalogenation of these forms 7-bromo-2,4-dien-6-ones (6a-b), 2,4-dien-6-ones (7a-b), and 14-hydroperoxy-2,4,7-trien-6-ones (8a-b). Woodward hydroxylation of dienone 6a produces 2-iodo-7-bromo-3-acetoxy-4-6-ketone 9 and 7-bromo-2,3-diacetoxy-4-6-ketone 10. 2-Iodo-3-acetoxy-4,7,14-trien-6-one 11 is prepared analogously from trienone 8a.  相似文献   

11.
The uptake of -, -, -, hexakis-2,6-di-O-methyl--(DM--), heptakis-2,6-di-O-methyl--(DM--) and heptakis-2,3,6-tri-O-methyl-- (TM--) cyclodextrins (CD's) by Na-, Ca-, and Cu-montmorillonites has been studied at 25°C. Each of -, DM--, DM--, and TM--CD's forms a complex with all of these montmorillonites in which the guest molecules are arranged as a monolayer with their open faces parallel to the silicate sheet of montmorillonite. On the other hand, -CD is intercalated only by the Na form and -CD cannot be taken up by any of the clays used. The interlayer spacing of the -CD complex varies from 18.0 to 21.5 Å with replacement of the interlayer cation, but those of the methylated -and -CD complexes remain unchanged, beingca. 21 and 18 Å, respectively. The different behaviour of the parent and methylated CD's is explained in terms of the structural and physicochemical characteristics of the individual CD's and interlayer cations.  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.
The binding of a series of alkane-,-diols, HO(CH2)nOH, n = 4 to 7, to - and -cyclodextrin (CD) has been studied by measurements of partial molar volumes (PMVs) and isentropic partial molar compressibilities (PMCs) at 25°C. From the PMV and PMC data, changes in the partial molar quantities upon going from a free state in aqueous solution to a complexed state were evaluated for the diols. Negative changes in PMV and PMC were observed for complex formation with -CD, while positive values were obtained for the -CD complexes. Equilibrium constants for the different complexes, assuming the formation of 1:1 complexes, were evaluated from the PMV and/or PMC data, and were found to increase with increasing chain length of the included diol for both - and -CD complexes. The equilibrium constant for complex formation is generally higher for the -CD than for the -CD complexes.  相似文献   

14.
FT-Raman spectra of 2-, 3-, and 4-chlorostyrene included in-cyclodextrin (CD),glycerol ether -CD, -CD,sulfated -CD, andglycerol ether -CD were recorded.In the inclusion complexes, the area of the vinyl(C=C) band decreased remarkably, whereasthe area of the phenyl (C=C) band increasedcompared to those of liquid 2-, 3-, and 4-chlorostyrene,respectively. From the results, the inclusion structures of2-, 3-, and 4-chlorostyrene were discussed.  相似文献   

15.
The following potential antagonists to amino acids were synthesized: -(6-quinolyl)--alanine, -(8-quinolyl)--alanine, and -(2-phenyl-4-carboxy-6-quinolyl)--alanine.  相似文献   

16.
17.
By chromatography on Polikhrom-1, silica gel, and Florisil, an ethanolic extract of the digestive organs of the starfishPatiria pectinifera has yielded the steroid polyols 5-cholestan-3,6,8,15,16,26-hexaol and 5-cholestan-3,4,6,7,8,15,16,26-octaol 6-(sodium sulfate). The structures of the compounds have been shown by spectral characteristics and chemical transformations.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 738–741, November–December, 1984.  相似文献   

18.
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   

19.
Three new glycosides, D1, D2, and D3, have been isolated from the Far Eastern starfishDistolasterias nipon. They have been identified by chemical and physicochemical methods as 5-cholestane÷3,6,8,15,24-pentaol 3,24-di-O--D-xylopyranoside, t-cholest-22-ene-3,6,8,15,24-pentaol 3,24-di-O--D-xylopyranoside (II), and 5-cholestane-3,6,8,15,24-pentaol 24-O--D-glucopyranoside 3-O--D-xylopyranoside (III).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. 250–255, March–April, 1987.  相似文献   

20.
From the leaves of Crimean ivy we have isolated the previously known glycosides 3-O--L-Arap-28-O-[O--L-Rhap-(14)-O--D-Glcp-(16)--D-Glcp]hederagenin, 3-O-[O--L-Rhap-(12)--L-Arap]-28-O-[O--L-Rhap-(14)-O--D-Glcp-(16)--D-Glcp]oleanic acid and -hederagenin, and 3-O-[O--L-Rhap-(12)--L-Arap]-28-O-[O--D-Glcp-(16)--D-Glcp]hederagenin and a new one: tauroside H1 — 3-O-[O--L-Rhap-(12)-O--L-Arap]-28-O-[O--L-Rhap-(14)-O--D-Glcp-(16)--D-Glcp]echinocystic acid.M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 522–528, September–October, 1992.  相似文献   

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