N—BOC—L—Tyr制备方法的改进

标题化合物，一般以叔丁氧羰基肼和Ｌ－酪氨酸通过叠氮法获得，但常得到Ｎ－ＢＯＣ－Ｌ－Ｔｙｒ和Ｎ，Ｏ－ｄｉＢＯＣ－Ｌ－Ｙｙｒ的混合物，极能分离纯化，作者研究在导入ＢＯＣ后，以ＮＨ３为选择脱保护试剂，并采用彻底酸化试剂避免了原酸化步骤中胶化的问题，使双保护产物转化成目标产物，产品纯净，收率高。

THE IMPROVEMENT ON THE PREPARATION METHOD OF N BOC L TYR

The title compound is synthesized from t butyl carbazate [(CH 3) 3COCONHNH 2] and L Tyr by azide method. But it usually results in mixed products of N BOC L Tyr and N, O diBOC L Tyr which is extremely difficult to separate and purify. Upon the basis of research and arter the introduction of BOC, ammonia is used as the selective deprotecting regent and a way of perfect acidification is adopted to avoid the inconvenience of gelation in the acidizing step, which makes N, O diBOC L Tyr into the goal product and results in good yield.