A new, mild, general, and efficient synthesis of N-protected α-amino acid hydrazides is described. This two-step preparation uses N-aminophthalimide as protected hydrazine to prepare N-protected α-amino acid hydrazide precursors, and subsequent dephthaloylation with an aminomethyl polystyrene resin yields N-protected α-amino acid hydrazides. It has the advantages of avoiding the use of the toxic hydrazine reagent and being compatible with the most commonly used N-protecting groups. This strategy is particularly interesting in the case of N-(9-fluorenylmethoxycarbonyl)-protected amino acids. Within the limits of chiral HPLC detection, no epimerization is apparent.
描述了一种新的、温和的、通用的且高效的N-保护
α-氨基酸酰
肼合成方法。该两步法利用N-
氨基
酞菁作为保护性酰
肼制备N-保护
α-氨基酸酰
肼前体,随后通过
氨基甲基聚
苯乙烯树脂的去
酞菁化反应得到N-保护
α-氨基酸酰
肼。其优点在于避免了使用有毒的酰
肼试剂,并与最常用的N-保护基团相容。对于N-(9-
芴基甲氧羰基)保护的
氨基酸而言,该策略尤为有趣。在手性HPLC检测的限制范围内,未观察到外消旋化现象。