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1.
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   

2.
The structures of two triterpene oligosides from the holothurianStichopus cloronotus (Brandt) have been established; they are: 23-acetoxy-3-[O--D-quinovopyranosyl-(12)--D-xylopyranosyloxy]holost-7(8)-ene and 23-acetoxy-3-[O--D-glucopyranosyl-(12)--D-xylopyranosyloxy]holost-7(8)-ene.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. 181–184, March–April, 1981.  相似文献   

3.
A new cycloartane glycoside of the cyclostipuloside C series, 3-O--D-xylopyranoside-6,16-di-O--D-glucopyranoside-20S-24R-epoxycycloartan-3,6,16,25-tetraol is isolated from aerial organs of Tragacantha stipulosa Boriss.  相似文献   

4.
Solasodine (I) has been subjected to a number of transformations. The following compounds have been obtained from it by described procedures: 3-acetoxypregna-5,16-dien-20-one (II), 3-acetoxypregn-5-en-20-ol (III), and 3-acetoxypregn-5-en-20-ol (IV). The oxidation of (III) and (IV), the formation of an oxime, and the reduction of the oxime with sodium in ethanol, followed by Hess methylation, has led to 20-dimethylaminopregn-5-en-3-ol (IX) and to 20-dimethylaminopregn-5-en-3-ol (X). From compounds (IX) and (X), by analogy with (III) and (IV) by their oxidation and the preparation of oximes, which were then reduced and methylated, the following were obtained: 3,20-bisdimethylaminopregnane (XVII) and 3,20-bisdimethylaminopregnane (XVIII), and also quaternary salts of the latter.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 370–374, May–June, 1980.  相似文献   

5.
Five new steroid alcohols have been isolated in the form of their acetates from extracts of the spongeHalichondria sp 1 by column chromatography on silica gel and they have been identified as 24-isopropyl-5-cholest-22z-en-3-ol, 24-isopropylcholesta-5, 22Z-dien-3-ol, 24,24,26,26-tetramethylcholesta-5,25(27)-dien-3-ol, 24,24,26,26-tetramethylcholesta-5,22E,25(27)trien-3-ol, and 24-isopropenyl-25-methylcholesta-5,22E-dien-3-ol. The structures were established by an analysis of spectral characteristics.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. 232–239, March–April, 1985.  相似文献   

6.
Two new steroid glycosides, which have been called echinasterosides B1 and B2 have been isolated from the starfishEchinaster sepositus. Using chemical transformations (methylation, hydrolysis) and also spectral methods (1H and13C NMR spectroscopy and GLC-MS) the complete chemical structure of B1 has been established as 15-acetoxy-5-cholestane-3,4,6,8,24-pentaol 24-O[O-(2)O÷ methyl--D-xylopyranosyl)-(13)--L-arabinofuranoside] (I) and that of glycoside B2 as 5-cholestane-3,4,6,8,15,24-hexaol 24-O-[O÷(2-O-methyl--D-xylopyranosyl)-(13)--L-arabinofuranoside] (II).Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Pirodnykh Soedinenii, No. 2, pp. 246–249, March–April, 1987.  相似文献   

7.
The new lanostane methylsteroid orbigenin, the structure of which is 23,24-lanost-9(11)-en-3,7,16,19,23,24,25-heptaol, was isolated from Astragalus orbiculatus Ledeb. (Leguminosae). The structure of the new triterpenoid, the first lanostanoid from plants of the Astragalus genus, was determined using electron-impact mass spectrometry and PMR and 13C NMR spectroscopies interpreted using J-modulation, DEPT, and the 2D NMR methods: 1H-1H COSY, HSQC, and HMBC.  相似文献   

8.
Zusammenfassung N-Dichloracetyläthanolamin (I) wurde über das mit SOCl2 erhaltene N-Dichloracetyl--chloräthylamin (II) durch Alkali in das 2-Dichlormethyl-oxazolin (III) übergeführt, dessen sehr leicht erfolgende hydrolytische Umwandlungen beschrieben werden. Kondensation von 4-Nitrobenzaldehyd mit (III) erfolgt ohne jedweden Katalysatorzusatz unter den mildesten. Bedingungen an der überaus reaktiven Methingruppe des Dichlormethylrestes von (III) zu 2-[-(4-Nitrophenyl)--oxy-, -dichloräthyl]-oxazolin (VI), dessen Konstitution an Hand eines O-Acetats und durch die saure Hydrolyse zu einer -(4-Nitrophenyl)-, -dichlorhydracrylsäure und Äthanolamin bewiesen wird.Herrn Prof. Dr.L. Ebert zum 60. Geburtstag gewidmet.  相似文献   

9.
Sterol -D-xylopyranosides and arabinopyranosides in a ratio of 9:1 have been isolated from a lipid extract of the musculocutaneous sac of the Far Eastern holothurianC. japonica. The main components of both glycosidic fractions were identified as derivatives of cholesta-7,22-diene-3-ol, cholest-22-en-3-ol, 5-cholestan-3-ol, 24-ethylcholesta-7,22-dien-3-ol, and 24-methylene-, 24-methyl-, and 24-ethyl-cholest-22-en-3-ols.Institute of Immunology, Ministry of Health of the USSR, Moscow. M. M. Shemyakin Institute of Biorganic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 54, pp. 615–620, September–October, 1984.  相似文献   

10.
A new ecdysteroid (rhapisterone B) has been isolated from the seeds ofRhaponticum cathamoides (Willd.) Iljin. (familyCompositae). It has been shown that it is 2, 3, 11, 14, 20R, 24-hexahydroxy-5-cholest-7-en-6-one.Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 806–808, November–December, 1991.  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.
Summary It has been shown that the roots ofBryonia alba contain cholest-7-en-3-ol, 24-methylcholest-7-en-3-ol, 24-ethylcholest-7-en-3-ol, 24-methylenecholest-7-en-3-ol, 24-ethylidenecholest-7-en-3-ol, 24-ethyl-4-methylcholest-7-en-3-ol, 24-ethylidene-4-methylcholest-7-en-3-ol, and also previously undescribed 3-O--glucopyranosides of the above-mentioned sterols.A. L. Mndzhoyan Institute of Fine Organic Chemistry, Academy of Sciences of the Armenian SSR, Erevan. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 353–360, May–June, 1977.  相似文献   

13.
Orbicoside, a new lanostane glycoside and the first from plants of the Astragalus genus, was isolated from the aerial organs of Astragalus orbiculatus Ledeb. (Leguminosae). It has the structure 23,24-lanost-9(11)-en- 3,7,16,19,23,24,25-heptaol 3-O--D-xylopyranoside. The structure of orbicoside was established using PMR and 13C NMR, which were interpreted using DEPT and 2D NMR spectroscopies 1H-1H COSY, HSQC, and HMBC.  相似文献   

14.
We discuss a generalized electronic diabatic (GED) approach to diagonalize the exact Hamiltonian of an n-electron system which embeds an external background of positive charges. This Hamiltonian, denoted by e(q,), is defined in an inertial frame, and it contains a quantum part (the electrons with coordinates q) and a classical part (the external charges in a three-dimensional configuration ). We derive a GED basis set { k (q)} using an operator e(q,0) for a single configuration 0, and then show that these are also eigenfunctions for any other e(q,); only the ordering of eigenvalues may depend on (i.e., k=k()). The GED functions can also be used to represent the eigenstates of a fully quantum-mechanical system of electrons and nuclei. We discuss briefly the differences between the present procedure and the standard Born–Oppenheimer (BO) technique in the clamped-nuclei approximation. As illustration, we show how chemical changes emerge as transitions among diabatic states mediated by an electromagnetic field.  相似文献   

15.
Zusammenfassung Die Synthese von 3, 16-Diacetoxy-5 -pregnan-20-on (VI) aus 3-Acetoxy-5 -pregn-16-en-20-on und eine verbesserte Darstellung von 3, 16-Diacetoxy-5 -pregnan-20-on (III) aus 3-Acetoxy-pregna-5, 16-dien-20-on werden beschrieben.  相似文献   

16.
The disposition of cholesterol inside the -cyclodextrin cavity(-CD) was deduced from oxidation of cholesterol secondary alcoholgroups by Ca(OCl)2 and H2O2 in thepyridine–acetic acid system. The amount of cholest-4-ene-3-one formedwas found to be proportional to the concentration of -cyclodextrin,resulting in 56.1% of ketone. The oxidation rate was enhanced by-cyclodextrin and its methyl, polymer and 1 : 1copper(II)–-cyclodextrin derivatives. Detailed investigationsinvolving UV-visible, 13C- and 1H-NMR(T1, 1D NOE and ROESY) spectroscopic studies were carried out.A binding constant value of 15,385 ± 1500 M-2 wasobtained for the 2 : 1heptakis-2,6-di-O-methyl--cyclodextrin(DM-CD) : cholesterolcomplex in chloroform from UV studies. Proton and solid state13C-CP MAS spectra of the -CD–cholesterol mixtureshowed large magnitude shifts for the protons from the wider end of the-CD cavity as well as those of ring A and ring B of cholesterol. Both1D NOE and ROESY measurements indicated the proximity between ring A andring B protons of cholesterol and the wider end protons of -CD andDM-CD. Besides, analysis of c,i and tau;m from T1measurements showed not only a lowering of rotational motions but a value of 0.016–0.048 for some of the cholesterol protons, typical of aweak complex. Based on these studies, a probable structure for the 2 : 1complex involving two molecules of -CD/DM-CD was proposed withportions of ring A and ring B being present inside the wider end of the-CD/DM-CD cavity and ring D and the side chain attached atposition 17, projecting into the wider end of the secondCD/DM-CD molecule.  相似文献   

17.
The thermal decomposition of the Co(II) complexes of 1-methylimidazoline-2(3H)-thione (MImt), general formula Co(MImt)2X2 (X=Cl, Br & I), have been studied in air and argon by means of TG and DTG as well as in nitrogen by DTA. Quantitative DTA has been used to derive reaction enthalpies (H R) from the melting and decomposition endotherms in nitrogen. Decomposition processes have been proposed for the complexes in air and in inert atmospheres. A mean coordinate bond dissociation energy (¯D) has been estimated for the Co-MImt bond in Co(MImt)2Cl2.Reaction end products in air have been identified by X-ray powder diffraction.
Zusammenfassung Die thermische Zersetzung von Kobaltkomplexen des 1-Methylimidazolin-2(3H)-thions (IMmt) der allgemeinen Formel Co(MImt)2X2 (X=Cl, Br, J) wurde in Luft und Argon mittels TG und DTG und in Stickstoff mittels DTA untersucht. Reaktionsenthalpien (Hr) wurden durch quantitative DTA aus den in Stickstoffatmosphäre erhaltenen endothermen Schmelz- und Zersetzungspeaks erhalten. Es wurden Mechanismen für die Zersetzungsprozesse der Komplexe in Luft und inerter Atmosphäre vorgeschlagen. Die mittelere Dissoziationsenergie (¯D) der koordinativen Bindung Co—MImt in Co(MImt)2Cl2 wurde bestimmt.In Luft erhaltene Reaktionsendprodukte wurden durch Röntgenpulverdiffraktometrie identifiziert.

1- -2()- () ()22, X=l, I, , . (H R) . . - ()2l2. , , - .


The author is grateful to Mr. J. R. Creighton, Newcastle upon Tyne Polytechnic, for technical assistance with this work and to Dr. F. Buttler, Teesside Polytechnic for mass spectral data and helpful discussion.  相似文献   

18.
One- and two-dimensional homo- and heteronuclear correlation proton, carbon, proton—proton, and proton—carbon NMR spectra of fifteen drimanic sesquiterpenoids: 11,12-dibromodrima-5,8-dien-7-one, drim-8-en-7-one, 11-hydroxydrim-8-en-7-one, 11,12-dihydroxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 8,9-epoxydriman-7-one, 8,9-epoxydriman-7-ol, 11,12-diacetoxydrim-8-en-7-ol, drimane-7,8,11-triol, 7,8-isopropylidenedioxydriman-11-al, 9, 11-dihydroxydrim-7-en-6-one, drimane-7,8,9-triol, drimane-7,8,11-triol, and drim-8-ene-7,11,12-triol were studied. The proton and carbon chemical shifts were assigned.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2589–2594, December, 2004.  相似文献   

19.
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   

20.
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   

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