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以2,6,6-三甲基环己-2-烯-1,4-二酮为原料, 经选择性羰基保护、Wittig反应、脱保护基、 腈基水解和还原等5步反应合成了目标化合物, 总产率可达6.0%. 相似文献
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Astrogorgiadiol is a naturally occurring Vitamin D analogue that, in cell culture, downregulates the production of the cytokine osteopontin (OPN). OPN has been implicated in virulent asthma, and OPN knockout mice do not develop osteoporosis. As we have pursued whole animal studies with astrogorgiadiol, we have increased the scale of the synthesis. We report an improved preparation of the A-ring synthon and the scale-up of the diasteromerically pure D-ring/sidechain chiron. 相似文献
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(Methylchlorosilyl)methyldichlorophosphines have been synthesized by the reaction of [dimethy(diethylamino)silyl]- or [methyl-bis(diethylamino)silyl]methylmagnesium chlorides with PCl3 in ether at –40÷–20 °C and subsequent treatment of the reaction mixture with dry HCl. The structures of the compounds thus obtained have been studied by31P,1H, and13C NMR spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 989–990, May, 1993. 相似文献
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M. A. Yurovskaya 《Chemistry of Heterocyclic Compounds》1987,23(9):919-934
Methods for obtaining alkylindoles, excluding the Fischer synthesis and direct alkylation, developed during the last 15 years are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1155–1172, September, 1987. 相似文献
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The synthesis of (-)-epibatidine has been accomplished utilizing a highly exo-selective asymmetric hetero Diels-Alder reaction. The key steps employed to transform the resulting bicycle into the natural product include a fluoride-promoted fragmentation and a Hofmann rearrangement. Reaction: see text. 相似文献
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[reaction: see text] The first synthesis of (-)-dysiherbaine has been accomplished using intramolecular SN2 substitutions of a carbamate anion on an epoxide and an alkoxide on a secondary mesylate to efficiently construct the bicyclic skeleton stereospecifically from xylose. A general sequence has been developed to introduce an allyl group and convert it to the alanine side chain that should be useful for the construction of dysiherbaine analogues. 相似文献
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研究了以(-)-α-蒎烯为原料合成(-)-异松蒎酮的反应. 以四氢呋喃为溶剂, 硼氢化钠与三氟化硼乙醚溶液生成的硼烷不经分离直接与α-蒎烯发生反马氏加成反应, 生成二异松蒎烷基硼; 采用四水合过硼酸钠或NaOH-H2O2氧化硼氢化物得到(+)-异松蒎醇, 产率为89.5%, 纯度97.4%, 熔点为55~56 ℃, 比旋光度 +28.31 (c 5.55, CH3OH). 以钒磷氧化物为催化剂、双氧水作氧化剂, 将(+)-异松蒎醇氧化得到(-)-异松蒎酮, 产率88% 以上, 纯度96.0%, 比旋光度为 -10.58 (c 5.51, CH3OH). 采用IR, MS, 1H NMR, 13C NMR等对(+)-异松蒎醇和(-)-异松蒎酮结构进行了表征. 相似文献
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The synthesis of a biologically active anlogue of the antitumor agent quadrone, termed descarboxylquadrone (), is described. 相似文献
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New marine eicosanoid clavulones (claviridenones) were synthesized from the Corey lactone and D-glutamic acid. 相似文献
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The preparation of the diastereomerically pure beta-tetralone ketal 4 is reported. Intramolecular alkylidene C-H insertion followed by hydrolysis of 4 proceeded to give the enantiomerically pure cyclopentene 15. The key step in this synthesis was the bis-intramolecular cyclization of keto aldehyde 2 to give the tetracyclic intermediate 20. Enone 20 was converted over several steps to (-)-morphine 1. 相似文献
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Synthesis of (-)-delobanone 总被引:1,自引:0,他引:1
On irradiation in the presence of Fe(CO)(5) under a CO atmosphere, the alkenyl cyclopropane 2 underwent smooth ring expansion to give the sesquiterpene (-)-delobabone 3. The alkenyl cyclopropane 2 was prepared from the enantiomerically enriched epoxide 1. 相似文献
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Improved, convenient, and reliable routes for the synthesis of 4-, 5-, 6-, and 7-azaindole, 7-methyl-4-azaindole, 7-methyl-6-azaindole, and the hitherto unreported 7-amino-4-azaindole are described. The syntheses have been accomplished either by significant modifications to established procedures or by new methods which afford the compounds in improved yields. 相似文献
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Published data on methods for the synthesis of the antitumor compound Ftorafur by the tetrahydrofurylation of 5-fluorouracil and its derivatives and also by fluorination, cyclization, solvolysis, oxidation, and other reactions are reviewed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1590–1620, December, 1991.The authors thank T. Shidlovskaya for assitance in the compilation of the tables. 相似文献