Diastereoselective Synthesis of γ-Phthalimido-β-Hydroxy Esters and N-Protected 4-Amino-1,3-Diols Starting from Natural α-Amino Acids
摘要:
An efficient diastereoselective synthesis of gamma-phthalimido-beta-hydroxy esters and N-protected 4-amino-1,3-diols, starting from natural amino acids is described. The key synthetic strategies involve diastereoselective reduction of gamma-phthalimido-beta-keto esters with NaBH4 as hydride reducing. The diastereoselective reduction has been found to be highly selective if carried out in methanol at -78 degrees C. Furthermore, the resulting diastereomeric mixture of the reduced products was successfully and cleanly separated by column chromatography.
Diastereoselective Synthesis of γ-Phthalimido-β-Hydroxy Esters and N-Protected 4-Amino-1,3-Diols Starting from Natural α-Amino Acids
摘要:
An efficient diastereoselective synthesis of gamma-phthalimido-beta-hydroxy esters and N-protected 4-amino-1,3-diols, starting from natural amino acids is described. The key synthetic strategies involve diastereoselective reduction of gamma-phthalimido-beta-keto esters with NaBH4 as hydride reducing. The diastereoselective reduction has been found to be highly selective if carried out in methanol at -78 degrees C. Furthermore, the resulting diastereomeric mixture of the reduced products was successfully and cleanly separated by column chromatography.