共查询到20条相似文献,搜索用时 62 毫秒
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本文对固相肽合成中得到普遍应用的四种接肽方法的活化方式、反应途径、优点与不足及近年来的进展情况作了较为详细的介绍相综述。 相似文献
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乙基二苯甲酰甲烷是一种光吸收性能良好的化合物。该法以苯甲酸乙酯和苯乙酮为起始原料,经克莱森缩合生成二苯甲酰甲烷,再与溴乙烷进行烷基化反应,最后生成乙基二苯甲酰甲烷,并对合成产物进行结构分析及紫外光吸收性能表征。 相似文献
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ZHANG Zhong-Biao HE Da-Yong CHI Guo-Chen CHEN Ru-YuState Key Laboratory of Elemento-Organic Chemistry Institute of Elemento-Organic Chemistry Nankai University Tianjin China 《中国化学》1997,15(6):548-552
A convenient procedure for the preparation of some new germasesquioxides containing phosphonyl groups carried by an intramolecular catalytic Mannich-type reaction is reported. 相似文献
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A convergent total synthesis of the Annonaceous acetogenin squamostolide, in a longest linear sequence of nine steps from d-mannitol, is reported. Central to the efficiency of the synthesis is a highly selective tandem ring-closing/cross metathesis step in which lactone formation and fragment coupling are accomplished. 相似文献
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Rohani Prasad Burman Shantanu Gupta Jyoti Bhatti Krishan Verma Devendra Rajak 《Natural product research》2019,33(8):1147-1157
First total synthesis of carpatamide-A 7a, cytotoxic arylamine derivative isolated from marine derived Streptomyces sp., was achieved in twelve steps with overall yield of 24% with seven longest linear steps. In the penultimate step, dienoic acid 13 and an amino-phenylpropionic acid methyl ester core 21 were coupled to synthesize methylated derivativative of carpatamide-A 22 followed by demethylation of the intermediate with BBr3 to accomplish carpatamide-A 7a. Both precursors 13 and 21 were synthesized from readily available starting materials i.e. isovaleraldehyde 8 and 2, 4-dihydroxy benzaldehyde 14. 相似文献
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A catalytic process for the synthesis of optically active C4-substituted tetrahydroindandiones using an asymmetric intramolecular aldol condensation reaction was developed. When 30 mol% of phenylalanine and 50 mol% of pyridinium p-toluenesulfonate were used under highly concentrated conditions, a variety of C4-substituted tetrahydroindandiones and octahydronaphthalenediones were obtained in high yield (up to 89% yield) and high enantiomeric excess (up to 94% ee). One of the products was successfully transformed into the key intermediate for the synthesis of the phosphatidylinositol 3-kinase inhibitor wortmannin, achieving formal total synthesis of (+)-wortmannin. 相似文献
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The synthesis of a new series of six-membered N,N'-diarylsubstituted methylene-bis-dihydro-2H-1,3-benzoxazines (Sa-e) was achieved in excellent yields by Mannich-type condensation of N,N'-diarylsubstituted methylene-bis-o-hydroxybenzyl amines (4a-e) with formaldehyde in chloroform at reflux. These amines (4a-e) were obtained by the reduction of N,N'-diarylsubstituted methylene-bis-o-hydroxybenzyl imines (3a-e) with NaBH4, which inturn were obtained by the condensation of methylene-bis-salicylaldehyde (2) with various substituted arylamines. 相似文献
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A convergent and scalable synthetic route to a tetracyclic oligostilbenoid natural product, diptoindonesin G, is described where Suzuki-Miyaura cross-coupling and intramolecular Friedel-Crafts acylation were employed to construct the central C ring of diptoindonesin G. Two fragments for cross-coupling reaction were readily synthesized with similar efficiency. 相似文献
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R. F. Bayfield E. R. Cole 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):19-23
Abstract A study has been made of photocatalyzed interchange reactions of aromatic sulfenamides. The significance of the results in relation to the relative ease of S[sbnd]N and S[sbnd]S bond fission is discussed, together with possible mechanisms of interchange. Relevance to industrial processes is noted. 相似文献
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The synthesis of a new series of six-membered N,N′-diarylsubstituted methylene-bis-dihydro-2H-1,3-benzoxazines (5a-e) was achieved in excellent yields by Mannich-type condensation of N,N′-diarylsubstituted methylene-bis-o-hydroxybenzyl amines (4a- e) with formaldehyde in chloroform at reflux. These amines (4a-e) were obtained by the reduction of N, Nr-diarylsubstituted methylene-bis-o-hydroxybenzyl imines (3a-e) with NaBH4, which inturn were obtained by the condensation of methylene-bissalicylaldehyde (2) with various substituted arylamines. 相似文献