We have found that a boronic acid catalyzed amidation of an N -hydroxy amino acid methyl ester with amino acid tert -butyl esters gave N -hydroxy dipeptide derivatives in good yields without any racemization. The protecting groups on the nitrogen atom could be easily removed by heterogeneous hydrogenation conditions.

中文翻译：

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硼酸催化合成二肽

我们已经发现硼酸催化N-羟基氨基酸甲酯与氨基酸叔丁酯的酰胺化以良好的产率得到N-羟基二肽衍生物而没有任何外消旋化。氮原子上的保护基团可以通过非均相氢化条件轻松去除。