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441.
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
442.
A novel catalytic synthesis of alkylaromatic hydrocarbons (AArH) containing C7-C8 has been achieved using C2-C4, alkanes as alkylating reagents on high silica zeolites of the pentasil type. It has been established that the yield of AArH during the reaction between benzene and alkanes varies in the order C2H63H8C4C10 (450–600°C). Modification of the zeolite by additions of Pt, Zn, and Ga results in a lowering of the reaction temperature (by 100°C) and alters the selectivity of the alkylation process. On passing from flow to static conditions and raising the pressure to 2–4 MPa the AArH yield doubles and reaches 70–75% in the case of C3-C4 hydrocarbons.For previous communication, see [1].Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2228–2232, October, 1991. 相似文献
443.
The results are given of an investigation of three species of the genusHaplophyllum: H. villosum, H. kowalenskyi, andH. tenue, fromwhich five substances of coumarin nature have been isolated. Of them, two substances (I and II) have been identified as scopoletin and lomatin isovalerate, respectively, while suitable structures have been established for the new compounds tenuidin, villosin, and tenudiol. It has been shown that the coumarin composition of the plants changes with the growth site.Leningrad Sanitary-Hygienic Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 800–803, November–December, 1980. 相似文献
444.
M. I. Isaev 《Chemistry of Natural Compounds》1996,32(4):550-552
The 17E- and 17Z- isomers of 3-[O--L-arabinopyranosyl-(12)-ß-D-xylophranosyloxy]-6-(-D-xylopy-ranosyloxy)-25-norcycloart-17-en-16-on-24-oic acid have been synthesized in four stages from askendoside D.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 565–567, July–August, 1996. Original article submitted January 15, 1996. 相似文献
445.
M. I. Isaev 《Chemistry of Natural Compounds》1992,28(5):461-463
The structure of a new cycloartane glycoside, cycloaraloside B, isolated from the roots ofAstragalus amarus Pall. (Leguminosae) has been established on the basis of chemical transformations and spectral characteristics: it is 20R,24S-epoxycycloartane-3β,6α,16β,25-tetraol 3-O-[O-α-L-rhamnopyranosyl-(1→2)-(6-O-acetyl-β-D-glucopyranoside)]. 相似文献
446.
Triterpene glycosides ofAstragalus and their genins. XIV. Askendoside A fromAstragalus taschkendicus
M. I. Isaev M. B. Gorovits N. D. Abdullaev N. K. Abubakirov 《Chemistry of Natural Compounds》1984,19(5):552-556
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
447.
M. I. Isaev 《Chemistry of Natural Compounds》1995,31(6):690-693
The roots of Astragalus taschkendicus Bunge (Leguminosae) have yielded the new cycloartane glycoside askendoside F which is 24R-cycloartan-3β,6α,16β,24, 25-pentaol 3-O-[O-α-L-arabinopyranosyl-(1→2)-β-D-xylopyranoside] 25-O-D-glucopyranoside, and D-3-O-methyl-chiro-inositol. 相似文献
448.
T. V. Ganenko M. I. Isaev V. I. Lutskii A. A. Semenov N. D. Abdullaev M. B. Gorovits N. K. Abubakirov 《Chemistry of Natural Compounds》1986,22(1):61-65
A new glycoside of the cycloartane series — cyclofoetoside A — has been isolated from the epigeal part ofThalictrum foetidum L., and its structure has been established on the basis of chemical transformations and spectral characteristics as 24S-cycloartane-3,16,24,25-tetraol 3-0--L-arabinopyranoside 16-0-[0--L-rhamnopyranosyl-(16)--D-glucopyranoside].Pyatigorsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR; Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 66–71, January–February, 1986. 相似文献
449.
B. A. Imomnazarov M. I. Isaev S. S. Saboiev N. K. Abubakirov 《Chemistry of Natural Compounds》1991,26(5):555-558
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-3,6,16,25-tetraol 6-0--L-rhamnopyranoside 3-0--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
450.
The structures of two new cycloartane glycosides — cyclocarposides A and C, isolated from the herbAstragalus coluteocarpus Boiss. — have been established on the basis of spectral characteristics and chemical transformations. Cyclocarposides A and C are: 204R,24S-epoxycycloartane-3,6,17,25-tetraol 3-O-(2-O-acetyl--D-xylopyranoside)6-O-(2-O-acetyl--L-rhamnopyranoside) and 20R,24S-epoxycyloartane-3,6,16,25-tetraol 3-O-(2-O-acetyl--D-xylopyranoside) 6-O--L-rhamnopyranoside, respectively.Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Pamir Biological Institute, Tadzhikistan Academy of Sciences, Khorog. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 694–698, November–December, 1992. 相似文献