N-叔丁氧羰基-β-环己基天冬氨酸苄酯的合成

The experimental results of Benzyl Ntertbutyloxycarbonylβcyclohexylaspartate(Ⅰ)were reported in this paper.Starting from cheap and accessible Laspartic acid,the key intermediate of βcyclohexyl Ntertbutyloxycarbonylaspartate(Ⅱ)was prepared by esterification of aspartic acid via cyclohexanol catalyzed by sulfuric acid and further acylation via Boc2O.The synthesis of the title compound of(Ⅰ)was performed by benzylization of(Ⅱ)through benzyl bromide.The method is facile and the yield is higher than that in literatures.The structures of these compounds were verified by1H NMR and mp.,or by the corresponding authentic compounds.The discussion of the preparative conditions of Ⅰ and Ⅱ was also given.

N-叔丁氧羰基-DL-(±)-高酪氨酸的合成

目的制备用于新型多肽类药物全合成研究的非必需氨基酸N-叔丁氧羰基-DL-(±)-高酪氨酸(1)。方法以L-天冬氨酸(2)为原料,经N-甲氧羰基保护、分子内脱水酸酐化、与邻氯苯甲醚的Friedel-Crafts反应、10%钯碳催化氢化、48%氢溴酸脱N-甲氧羰基和酚甲醚保护、N-叔丁氧羰基保护6步反应合成了目标化合物。结果以总收率49.7%成功地合成了目标化合物1,其结构经电喷雾质谱(ESI-MS)、氢谱(1H NMR)和碳谱(13C NMR)确认。结论该合成路线具有原料价廉易得、操作简便、总收率高等优点。

环(D-天冬氨-D-脯)二肽的合成

以D-天冬氨酸和D-脯氨酸为原料,先合成N-叔丁氧羰基-D-天冬氨酸-β-苄酯和D-脯氨酸甲酯盐酸盐,然后经DCC缩合得直链二肽,再经Pd/C催化氢解,HCl/Et2O脱Boc保护,最后弱碱性条件下成环得环(D-天冬氨-D-脯)二肽,结构经ESI-MS、IR、1HNMR、13CNMR等表征。