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Construction of the Skeleton of Phthalascidin, Mechanism of the Formation of the Key Tricyclic Lactam Intermediate 总被引:1,自引:0,他引:1
Zhan Zhu LIU Ye WANG Shi Zhi CHEN* Institute of Materia Medica Chinese Academy of Medical Sciences& Peking Union Medical College Beijing 《中国化学快报》2002,13(8)
Phthalascidin is a structurally simplified version of Et-743, which is a potent anti-tumor marine natural product isolated from Ecteinascidia turbinata. Its antiproliferative activity is greater than that of the agents taxol, camptothecin, adriamycin, mitomycin C, cisplatin, bleomycin, and etoposide by 1-3 orders of magnitude. An elegant synthesis of Et-743 and phthalascidin has been reported by E. J. Corey and co-workers1,2. As part of our continuing program, we have also engaged in dev… 相似文献
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The mechanism of the formation of a key tricyclic lactam intermediate 3 was studied. It was found that the E-form compound 3 was transformed from the Z-form compound 4. The formation of 4 was a kinetically controlled process while the formation of 3 was a thermodynamically favorable one. A possible mechanism was given in this paper. 相似文献
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《European Polymer Journal》1986,22(10):769-773
Effects of the concentrations and ratio of reacting components and of temperature on the kinetics of reaction of N-propionyllactam (I) with potassium salt of lactam (KL) were studied for derivatives of ϵ-caprolactam, 8-octanelactam and 12-dodecanelactam. For ϵ-caprolactam, the initial rates of propagation, acylation of open-chain amide groups and condensation of growth centres were estimated. At the ratio of the starting components [I]0/[KL]0 = 0.5-3, the participation of the polymerization reaction is constant, amounting to ca 45% of the overall consumption of 1. The condensation reaction is 14–36% of the total consumption of I; its initial rate passes through a maximum at [I]0/[KL]0 = 2. With increasing permittivity of the medium, the total rate of consumption of I increases; in two media with the same bulk permittivity, however, the rates may differ by as much as one order of magnitude. 相似文献
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A method for the synthesis of glycoclusters by N-alkylation of N-glycyl-β-lactosylamine with N-chloroacetyl derivatives of β-lactosylamine and N,N’-iminodiacetyldilactosylamine has been developed. The glycoclusters obtained with two and three lactosylamine residues with
the amino group in the spacer were found to be suitable for further conjugation with carboxy-containing physiologically active
compounds.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 647–651, March, 2008. 相似文献
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《Tetrahedron letters》1986,27(12):1343-1346
The total synthesis of (−)-periplanone-B, the sex excitant pheromone of the American cockroach, Periplaneta americana is accomplished starting from (+)-limonene. 相似文献
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