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1.
The spatial structure of the sesquiterpene humulane alcohol juniferol, which is represented in the crystal by two conformers, IA and IB, differing by the conformation of the C2...C9 section, has been established by the x-ray structural method. The strain energies of the conformers have been calculated by the method of molecular mechanics. The barrier to the interconversion of the conformers by rotation of the C2...C9 section has been calculated; it amounts to 7–8 kcal/mole. This value of the transformation barrier permits the assumption that the two conformers also exist in solution, their interconversion being hindered.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Institute of Crystallography, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 757–762, November–December, 1990.  相似文献   

2.
A series of isomers of trans,trans- and trans,cis-eudesman-8,12-olides has been investigated by the method of molecular mechanics (MMM). Questions of the energetic suitability of particular isomers, of the influence of the orientation of substituents attached to the basic skeleton on their conformation, and of the relative stabilities of the conformers with different methods of linking the rings are considered. A. N. Nesmeyanov Institute of Heteroorganic Compounds, USSR Academy of Sciences, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 334–338, May–June, 1990.  相似文献   

3.
The conformational possibilities of four synthesized oligopeptides with the amino acid sequences 165–172, 173–184, 152–172, and 152–184 of the C-end of histone H1 of calf thymus above been studied in solution under various conditions by the method of circular dichroism. V. I. Nikitin Institute of Chemistry, Academy of Sciences of the Tadchik SSR, Dushanbe. Institute of Cytology, Academy of Sciences of the USSR, Leningrad. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 793–798, November–December, 1990.  相似文献   

4.
The spatial structure of the sesquiterpene humulane ester juniferdin, isolated fromFerula juniperina, has been established by the x-ray structural method. An analysis is given of the 11-membered humulane ring in comparison with the conformation observed in fexerol and juniferol. Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Institute of Crystallography, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinii, No. 4, pp. 494–499, July–August, 1991.  相似文献   

5.
Hypothetical models of the interaction of deoxypeganine molecules with a solvent have been considered by the MO LCAO quantum-chemical method in the AM1 approximation. Excited triplet states of deoxypeganine and its analogues have been calculated by the method of molecular interactions. A free-radical mechanism of photochemical oxidation has been proposed on the basis of the results obtained and of literature information. Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 546–548, September–October, 1992.  相似文献   

6.
A mixture of two alkaloids, d, ℓ-α- and β-scopodonnines, known earlier as synthetic products, has been isolated for the first time from the seed ofDatura inoxia. The spatial structure of β-scopodonnine dimethiodide has been established by the x-ray structural method. Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 532–537, July–August, 1991.  相似文献   

7.
An x-ray structural study has been made of the sesquiterpene lactone austricin: diffractometer, MoKα radiation, 1147 reflections, direct method, R=0.045. The spatial structure of the molecule has been determined. The conformation of the pentane carbocycle is 1α-envelope, of the heptane ring 1,10β, 7α-chair, and of the lactone ring 7α-envelope. The lactone ring is trans-linked with the guaiane skeleton. Institute of Organic Synthesis and Coal Chemistry, Kazakh SSR Academy of Sciences, Karaganda. A. N. Nesmeyanov Institute of Heteroorganic Compounds, USSR Academy of Sciences, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 788–791, November–December, 1989.  相似文献   

8.
The fractional composition of the polar lipids and also the fatty-acid composition of the main components of the phospholipids of the Chinese tallow tree have been studied. It has been established that in the seeds of the Chinese tallow tree there are 11 phospholipids, two glycolipids, and two phosphonolipids. The main fatty acids of the phospholipids are palmitic and linoleic. I. G. Kutateladze Institute of Pharmatochemistry, Georgian Academy of Sciences, Tbilisi. Institute of Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 619–621, September–October, 1991.  相似文献   

9.
A method has been developed for obtaining tritium-labeled analogues of β-indolylacetic acid and of 6-benzylaminopurine by the method of isotopic catalytic exchange. The localization of cytokinin- and auxin-binding proteins in cotton seedlings has been investigated. A. S. Sadykov Institute of Bioorganic Chemistry, Uzbekestan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 699–702, November–December, 1992.  相似文献   

10.
The new germacranolide argolide has been isolated from the epigeal part ofArtemisia glabella, and its structure has been shown by its conversion into oxopelenolide B. From the results of an x-ray investigation it is suggested that argolide has the spatial structure of 3-oxo-4α,7α,6β(H)-germacra-1(10),11(13)-dien-6,12-olide. Institute of Organic Synthesis and Coal Chemistry, Kazakh Academy of Sciences, Karaganda. A. N. Nesmeyanov Institute of Organometallic Chemistry, Russian Academy of Sciences, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 653–657, September–October, 1991.  相似文献   

11.
A sesquiterpene glucoside has been isolated from a tissue culture ofScorzonera hispanica, and its structure has been established by mass spectrometry and two-dimensional NMR as 6,9-dihydroxy-4,10,14,15-tetradehydroguaian-6,12-olide 9-O-β-D-glucopyranoside. Irkursk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 640–645, November–December, 1992.  相似文献   

12.
α-Santonin has been aminolyzed with dimethylamine. The spatial structure of the resulting dimethylamide has been established by the x-ray structural method. Institute of Phytochemistry, Academy of Sciences of the Republic of Kazakhstan, 470032, Republic of Kazakhstan, Karaganda, ul. Erzhanova, a/ya 19, fax (3212) 51 10 23. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 764–767, November–December, 1998.  相似文献   

13.
A method is proposed for introducing one, two, or three alkyl substituents into positions 4 and 6 of the cyclohexane-1, 3-dione molecule by successive alkylation under the action of strong bases. (±)-Angustione (a natural β-diketone) has been synthesized. Institute of Bioorganic Chemistry, Academy of Sciences of the Belorussian SSR, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 460–463, July–August, 1991.  相似文献   

14.
A new triterpene glycoside of the cycloartane series, which has been called cyclocarposide, has been isolated from the epigeal part of the plantAstragalus coluteocarpus Boiss. (Leguminosae). The structure of cyclocarposide has been established on the basis of chemical transformations and spectral characteristics as 20R,24S-epoxycycloartane-3β,6α,16β,25-tetraol 6-0-α-L-rhamnopyranoside 3-0-α-D-xylopyranoside. Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Pamir Biological Institute, Academy of Sciences of the Tadzhik SSR, Khorog. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 653–656, September–October, 1990.  相似文献   

15.
New types of ligands for spherical ions have been designed as part of the molecular design strategy for supramolecular compounds. In particular, symmetric conformers of macrocycles, built of −(CH2)n−O−(n=3,4,5) fragments, which envelope the spherical ion in a complementary way, have been constructed. Alos, new types of “bracelentands” with different, “hardening” fragments are suggested. Using the molecular mechanics methods, the selectivity of complex formation of the ligands with respect to alkaline metal ions has been investigated. A. V. Bogatskii Physicochemical Institute, Ukrainian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 5, pp. 879–883, September–October, 1995. Translated by L. Smolina  相似文献   

16.
The chemical composition and structures of the steroid glycosides forming the active principle of the preparation “tribestan,” which is used for treating impotence and female infertility, have been studied. It has been shown that together with trillin, prosapogenin A of dioscin, trillarin, dioscin, gracillin, protodioscin, and protogracillin, tribestan contains a diosgenin rhamnoglucoside sulfated in position 4 of the glucose residue, the structure of which has been shown by chemical and physicochemical methods. Institute of Ecological Genetics, Academy of Sciences of the Moldavian SSR, Kishinev. Center for Biogenic Stimulators, Sofia, Bulgaria. N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 649–652, September–October, 1990.  相似文献   

17.
The α-monoglyceride of trans-O—methylmarmesinic acid and its phosphate and citrate derivatives have been synthesized. The structures of the compounds have been confirmed by IR, UV, PMR and13C and31P spectroscopies. A. B. Bekturova Institute of Chemical Sciences, Academy of Sciences of the Republic of Kazakhstan, Almaty, fax (3272) 61 57 65. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 452–455, July–August, 1998.  相似文献   

18.
The new sesquiterpene lactone anolide has been isolated from the epigeal part ofAchillea nobilis. From its spectral characteristics and the results of an x-ray structural investigation, the structure of 3α,4β-dihydroxy-1,5,7α(H),6β(H)-guaia-10(14),11(13)-dien-6,12-olide is proposed for anolide. Institute of Organic Synthesis and Coal Chemistry, National Academy of Sciences of the Republic of Kazakhstan, Karaganda. A. N. Nesmeyanov Institute of Organometallic Compounds, Russian Academy of Sciences, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 500–504, July–August, 1994.  相似文献   

19.
An immunosorbent has been obtained by conjugating mcABs 2C8.C7 to membrane proteins from cotton seedlings with BrCN-Sepharose 4B. As a result of the affinity chromatography of the total lectin-like proteins of the cotton plant on this sorbent, two fractions of polypeptides have been isolated, and these have been subjected to electrophoretic analysis. A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (371) 162 70 71. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 807–811, November–December, 1998.  相似文献   

20.
The results of an x-ray structural investigation of 2e-diethylamino-3e,4e-dimethyl-5e-phenyl-2a-thio-1,3,2-oxazaphospholane are discussed. It has been shown that the conformation of the 5-membered ring is that of a half-chair. Institute of Organic Synthesis and Coal Chemistry, Kazkh SSR Academy of Sciences, Karganda. A. N. Nesmeyanov Institute of Heteroorganic Compounds, USSR Academy of Sciences, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 386–389, May–June, 1990.  相似文献   

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