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1.
Known ecdysteroids — ecdysterone, ecdysterone 22-acetate, polypodin B, integristerone A, and sileneosides A and D — and a new phytoecdysteroid — polypodin B 22-acetate — have been found in the epigeal parts of the plantMelandrium turkestanicum (Rg1.) Vved. (family Caryophyllaceae).Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 480–483, July–August, 1990.  相似文献   

2.
Summary From the unsaponifiable fraction of an ethereal extract of the leaves ofBetula ermanii a new triterpene of the dammarane series — 20,24-epoxydammarane-3,6,25-trol (II) — and its 6-O-acetyl derivative (I) have been isolated.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 587–590, September–October, 1978.  相似文献   

3.
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   

4.
Two new clerodanolides — salvicinolide and salvicinolin — have been isolated from the epigeal part ofPulicaria salviifolia Bge inMem (fam. Compositae). Their structures have been established by an investigation of their spectral and physicochemical characteristics. It has been found that salvicinolide is capable of cyclizing at the C-6 and C-19 carbon atoms with the formation of a second lactone ring. The structure of 6-hydroxy-19-carboxy-trans-clero-3,13-dien-15-olide is proposed for salvicinolide, and 6,13-dihydroxy-19-carboxy-rans-cleroda-3,13-diene for salvicinolin.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent fax (3712) 40 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 594–598, July–August, 1997.  相似文献   

5.
Five individual triterpene glycosides — A, B, D, E, and F — which are hederagen-in mono- and biosides, have been isolated from the roots ofCaltha polypetala (Great Marsh Marigold), familyRanunculaceae. Glycosides E and F proved to be new compounds for which, on the basis of the results of acid and alkaline hydrolyses, methylation, methanolysis, and physicochemical methods of investigation, the following structures are proposed: E — hederagenin 3-0-D-glucopyranoside, 28-O-L-rhamnopyranoside; and F — heteragenin 28-O-[O-L-rhamnopyranosyl-(1 6)-D-glucopyranoside].I. G. Kutateladze Institute of Pharmacochemistry, Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 712–716, November–December, 1986.  相似文献   

6.
Two oligomeric proanthocyanidins have been isolated from the roots ofPolygonum coriarium. By a study of their physical properties and spectral characteristics and analysis of the results of chemical transformations, the chemical structures of these compounds have been established as: (–)-epicatechin-77[O--D-glucopyranosyl]3 O-⊃-D-glucopyranosyl (m-trigallolyl)-[(4-6)-(–)-epigallocatechin]2-(4-6)-(–)-epigallocatechin—T3; and (–)-epicatechin-3-O-galloyl-7-[O--D-glucopyranosyl]3O--D-glucopyranosyl galloyl-[(4-6)-(–)-epicatechin]4-(4-6)-(–)-epigallocatechin — T4.The materials of this paper were presented at the IInd International Symposium on the Chemistry of Natural Compounds (SCNC), Eskiehir, Turkey, October 22–24, 1966).Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 707–713, September–October, 1997.  相似文献   

7.
Summary A new phytoecdysone — integristerone A — has been isolated from the flower heads ofRhaponticum integrifolium. It has been shown that it is 1,2,3,14,20R,22R,25-heptahydroxy-5-cholest-7-en-6-one.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 813–819, November–December, 1977.  相似文献   

8.
A new glycoside of the cycloartane series — askendoside A — has been isolated from the roots ofAstragalus taschkendicus Bge. (family Leguminosae), and on the basis of chemical transformation and spectral characteristics its structure has been established as 3-[O--L-arabinopyranosyl-(12) -(3-O-acetyl--D-xylopyranosyl)-oxy]-24R-cycloartane-6, 16, 24, 25-tetraol.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 587–592, September–October, 1983.  相似文献   

9.
UB3LYP/6-311++g(2df,p) and RMP2/6-311++g(d,p) methods were used to calculate B—Z bond dissociation energies (BDE) of para-substituted phenylboranes (X—C6H4—BH—Z). It was found that the slopes () of regressions between B—Z BDEs and substituent p constants increase in the order B—Cl (between –0.24 and 0.21 kcal/mol) < B—H (0.06-0.33 kcal/mol) < B—F (0.48-0.78 kcal/mol) < B—CH3 (0.83–1.28 kcal/mol) < B—Li (2.62-3.73 kcal/mol). Since all the homolysis reactions give the same boron radical, the large variation of indicates that the substituent effects on energies of the ground-state molecules are important for the substituent effects on BDEs. However, the ground-state stabilization energies, calculated using either Nau's method or our method, do not show any correlation with the polarization of the B—Z bond as defined by the electronegativity difference between the group X—C6H4—BH and Z. Therefore, the theory that the remote substituent effects on Y—Z BDEs are dependent on the Y—Z polarity should be discarded.  相似文献   

10.
The structures of proanthocyanidins CS-3 and CS-4, isolated from the roots ofClementsia semenovii have been established on the basis of chemical and spectral studies. CS-3 is 7-O-(6-O-galloyl--D-Glcp O--D-Glcp O--D-Glcp O--D-Glcp O--D-Glcp)-(+)-catechin-(4—8)-(–)-epigallocatechin-(4—8)-(+)-catechin-(4—8)-(–)-epigaLLocatechin-(4—8)-(–)-epigallocatechin-(4—8)-(–)-epigallocatechin, and CS-4 is 3-O-galloyl-7-O-[6-O-galloyl--D-Glcp O--D-Glcp O--D-Glcp-(+)-gallocatechin-(4—8)-[(+)-catechin-(4—8)-(3-O-galloyl-(–)-epigallocatechin]2-(4—8)-(–)-epicatechin.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 50–58, January–February, 1999.  相似文献   

11.
Two alkaloids of a new type — komarovine and komarovidine — have been isolated from the epigeal part of theNitraria komarovii. Their structures — 3-(quinolin-8'-yl)--carboline and 3-(quinolin-8'-yl)-5,6-dihydro--carboline, respectively — have been established by synthesis.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 192–195, March–April, 1981.  相似文献   

12.
Two new diamines — [1,3-bis(5-phenyl-1,2,4-triazol-3-yl)-4,6-diamino]benzene and [1,3-di-(2-benzimldazolyl)-4,6-diamino]benzene — were synthesized from 4,6-dinitroisophthalic acid. Newheterocyclic systems — 3,5,9,11-tetraphenyl[benzo[1,2-a; 4,5-a]bis(1,2,4-triazolo[4,3-c]pyrimidine)] and 2,16-diphenyl[benzo[1,2-a;4,5-a']bis(pyrimido[1,6-a]benzimidazole)]—were obtained by reaction of the diamines with benzoyl chloride and subsequent cyclization.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1274–1277, September, 1977.  相似文献   

13.
Two new steroid glycosides of the spirostan series — karataviosides E and F — have been isolated from inflorescences ofAllium karataviense Regel. Smith degradation of these compounds has given a steroid sapogenin, karatavigenin C, which is (25S)-spirost-5-ene-2,3,24S-triol. Its structure was established from an analysis of spectral characteristics.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 736–740, November–December, 1983.  相似文献   

14.
    
A new sterol — 24 ethyl-25-methylcholesta-5,22-dien-3-ol — has been isolated by column chromatography on silica gel from extracts of the spongeHalichondria sp. Its structure has been established on the basis of an analysis of GLC-MS results and of PMR and13C NMR spectroscopy and has been confirmed by ozonolysis.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. 464–467, August–September, 1984.  相似文献   

15.
A new coumarin glycoside lariside — C21H26O13, mp 155–156°C (from methanol) — has been isolated from the epigeal part ofSalsola laricifolia Turcz. et Litw. On the basis of acid hydrolysis and spectral characteristics the structure of lariside has been established as 7-[O--D-apiofuranosyl-(1 2)--D-glucopyranosyloxy]-6-methoxy-2H-1-benzopyran-2-one.Institute of Chemistry, Academy of Sciences of the Mongolian Peoples' Republic, Ultan-Bator. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 288–291, May–June, 1986.  相似文献   

16.
A new sesquiterpene lactone, pyrethroidin, and a known one — 8-deoxycumambrin B — have been isolated from the epigeal part of the plantPyrethrum pyrethroides. The structure of 4,10-dihydroxy-1,5,7(H),6(H)-guaia-2,11(13)-dien-6,12-olide has been suggested for pyrethroidin.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 199–201, March–April, 1985.  相似文献   

17.
Two cyano-bridged assemblies, [FeIII(salpn)]2[FeII(CN)5NO] (1) and [FeIII (salpn)]2[NiII(CN)4] (2) [salpn = N, N-1,2-propylenebis(salicylideneiminato)dianion], have been prepared and structurally and magnetically characterized. In each complex, [Fe(CN)5NO]2– or [Ni(CN)4]2– coordinates with four [Fe(salpn)]+ cations using four co-planar CN ligands, whereas each [Fe(salpn)]+ links two [Fe(CN)5NO]2– or [Ni(CN)4]2– ions in the trans form, which results in a two-dimensional (2D) network consisting of pillow-like octanuclear [—MII—CN—FeIII—NC—]4 units (M = Fe or Ni). In complex (1), the NO group of [Fe(CN)5NO]2– remains monodentate and the bond angle of FeII—N—O is 180.0°. The variable temperature magnetic susceptibilities, measured in the 5–300 K range, show weak intralayer antiferromagnetic interactions in both complexes with the intramolecular iron(III)iron(III) exchange integrals of –0.017 cm–1 for (1) and –0.020 cm–1 for (2), respectively.  相似文献   

18.
Crystals of [Cu(o-Andp)(H2O)2] · 2H2O (where o-Andp2–is -anisidine-N,N-di-3-propionate) were synthesized and studied using X-ray diffraction analysis. The crystals are triclinic: a= 12.063(1) Å, b= 12.483(3) Å, c= 13.586(2) Å, = 91.29(1)°, = 111.67(1)°, = 104.00(1)°, V= 1830.5(5) Å3, space group P , Z= 2, and R= 0.0528 for 5965 reflections with I2(I). The two crystallographically independent complexes are isostructural. The tetragonal–bipyramidal coordination of copper(III) involves three O atoms, the N atom of the tetradentate ligand o-Andp2–, and two O atoms from water. The aminodipropionate group of the ligand (average Cu–O 1.939 Å and Cu–N 2.051 Å) and one of the coordinated water molecules (Cu–O(w) 1.991 Å) lie in the equatorial plane. The second water molecule (Cu–O(w) 2.32 Å) and the methoxy O atom of o-Andp2–(Cu–O 2.37 Å) are in the apical positions of the bipyramid.  相似文献   

19.
The reaction cellulase (EC 3.2.1.4)—sodium carboxymethylcellulose (Na-CMC) with different degrees of polymerization (n=140, 640 and 900) was investigated by the use of a modifiedMichaelis-Menten equation, valid for enzymatic hydrolysis of linear homopolymers. TheMichaelis-Menten constant [Km (M)=6.31·10–2mol/dm3] and the reaction rate constant (k +2=4.07·10–6s–1), which correspond to the enzymatic hydrolysis of a single bond in the homopolymer substrates are determined. The free energy ( =101 kJ/mol), which corresponds to the degradation and formation of a single bond in the enzyme—polymer substrate is also estimated. This energy expressed in electronvolt units is =1.39 eV. The ratio between the effective cross section of the reactive substrate bond and the active enzyme center is =1.22.
Kinetik der enzymkatalysierten Hydrolyse von Natriumcarboxymethylcellulose mit verschiedenem Polymerisationsgrad durch Cellulase
Zusammenfassung Die modifizierte Gleichung nachMichaelis-Menten wird bei der durch Cellulase (EC 3.2.1.4) katalysierten hydrolytischen Spaltung von Natriumcarboxy-methylcellulose (Na-CMC) verschiedenen Polymerisationsgrades (n=140, 640 und 900) angewandt. Es wurde dieMichaelis-Menten-Konstante [Km (M)=6.31·10–2mol/dm3] und die Reaktionsgeschwindigkeitskonstante (k +2=4.07·10–6s–1), die der enzymatischen Hydrolyse einer Einfachbindung im homopolymeren Substrat entspricht, berechnet. Die freie Energie ( =101 kJ/mol), die dem Abbau und der Bildung einer Einfachbindung im Enzym—Polymer-Substrat entspricht, wurde bestimmt. Diese Energie — ausgedrückt in Elektronvolt-Einheiten — beträgt =1.39 eV. Das Verhältnis zwischen den effektiven Querschnitten der reaktiven Substratbindung ( S ) und des aktiven Enzym-Zentrums ( E ) beträgt =1.22.
  相似文献   

20.
Coumaris ofHaplophyllum obtusifolium Ledeb. — obtusinin, capensin, and fraxetin 7-O--D-glucopyranoside — have been investigated by13C NMR spectroscopy. Several distinctive features of their NMR spectra have been observed. A complete assignment of the13C NMR spectra of these coumarins has been made and their structures have been confirmed.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 796–799, November–December, 1987.  相似文献   

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