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The proof of the structures of two isomeric alkaloids — nitramine and isonitramine — from two species of plants of the genusNitraria is given. Their diastereoisomerism with respect to the C7 asymmetric atom has been established. This is the first time that alkaloids with the structure of 2-azaspiro[5,5]undecan-7-ol have been found.  相似文献   
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It has been shown that it is possible to use the method of circular dichroism to determine the absolute configuration of the asymmetric center at C11 in the eudesmanolides. The orientations of the hydroxy group at C1 and of the methyl group at C4 in arabsin have been established.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 343–346, May–June, 1980.  相似文献   
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The reactions of benzoxazolinone and benzoxazolinethione with alkyl -chlorovinyl ketones have been studied. The reaction products are N-(-acylvinyl)benzoxazolinones and N-(-acylvinyl)benzoxazolinethiones. The reaction of alkali-metal salts of benzoxazolinone with alkyl -chlorovinyl ketones leads to the opening of the oxazolinone ring. The structures of the compounds synthesized have been studied by IR, mass, and PMR spectroscopy.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 507–511, July–August, 1983.  相似文献   
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Summary 6,7-Dimethoxy-2-methyl-1,2-dihydroisoquinolin-1-one and the new aporphine base 9-hydroxy-1,2,3,10-tetramethoxyaporphine, which has been called thalisopynine, have been isolated fromThalictrum for the first time.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnyk Soedinenii, No. 4, pp. 472–474, July–August, 1978.  相似文献   
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The spatial structure of the alkaloid kalidine obtained from the epigeal part ofKalidium gracile Fenzl. has been determined by IR and NMR spectroscopy and x-ray structural analysis. It has been established that it is the chloride of the trimethyl derivative of glycinamide.Institute of the Chemistry of Plant Substances of the Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 558–561, July–August, 1987.  相似文献   
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A study of the circular dichroism of chlorine-containing guainolides has shown that a negative Cotton effect in the 260-nm region correlates with the trans-linkage of the lactone ring in acroptilin, hyrcanin, chlorohyssopifolin B, elegin, and biebsanin. It has been established that this nature of the linkage does not change on relactonization and hydrogenation. A chloromethylene substituent at C4 causes a bathochromic shift of the lactone Cotton effect.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 650–652, September–October, 1979.  相似文献   
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A study of the circular dichroism of chlorine-containing guainolides has shown that a negative Cotton effect in the 260-nm region correlates with the trans-linkage of the lactone ring in acroptilin, hyrcanin, chlorohyssopifolin B, elegin, and biebsanin. It has been established that this nature of the linkage does not change on relactonization and hydrogenation. A chloromethylene substituent at C4 causes a bathochromic shift of the lactone Cotton effect.  相似文献   
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