Synthesis of Nα-Z, Nβ-Fmoc or Boc protected α-hydrazinoacids and study of the coupling reaction in solution of Nα-Z-α-hydrazinoesters
摘要:
The preparation of chiral orthogonally protected N-alpha-Z, N-beta-Fmoc- or Boc-alpha-hydrazinoacids derivatives, directly suitable for SPPS, is described in six steps with good yields starting from the corresponding alpha-aminoacids. The coupling reaction assays performed in liquid phase between N-alpha-Z-hydrazinoesters and N-Fmoc-alpha-aminoacids demonstrated the low reactivity of the hydrazinoester derivatives. However, we found that the acid fluoride method allowed the formation of hydrazinodipeptides almost quantitatively. (c) 2007 Elsevier Ltd. All rights reserved.
Synthesis of Nα-Z, Nβ-Fmoc or Boc protected α-hydrazinoacids and study of the coupling reaction in solution of Nα-Z-α-hydrazinoesters
摘要:
The preparation of chiral orthogonally protected N-alpha-Z, N-beta-Fmoc- or Boc-alpha-hydrazinoacids derivatives, directly suitable for SPPS, is described in six steps with good yields starting from the corresponding alpha-aminoacids. The coupling reaction assays performed in liquid phase between N-alpha-Z-hydrazinoesters and N-Fmoc-alpha-aminoacids demonstrated the low reactivity of the hydrazinoester derivatives. However, we found that the acid fluoride method allowed the formation of hydrazinodipeptides almost quantitatively. (c) 2007 Elsevier Ltd. All rights reserved.
The preparation of chiral orthogonally protected N-alpha-Z, N-beta-Fmoc- or Boc-alpha-hydrazinoacids derivatives, directly suitable for SPPS, is described in six steps with good yields starting from the corresponding alpha-aminoacids. The coupling reaction assays performed in liquid phase between N-alpha-Z-hydrazinoesters and N-Fmoc-alpha-aminoacids demonstrated the low reactivity of the hydrazinoester derivatives. However, we found that the acid fluoride method allowed the formation of hydrazinodipeptides almost quantitatively. (c) 2007 Elsevier Ltd. All rights reserved.