A convenient, stereodivergent approach to the enantioselective synthesis of N-Boc-aminoalkyl epoxides
作者:Patricia Castejón、Mireia Pastó、Albert Moyano、Miquel A Pericàs、Antoni Riera
DOI:10.1016/0040-4039(95)00415-9
日期:1995.4
An efficient, stereodivergent and enantioselective synthesis of N-Boc-aminoalkyl epoxides has been developed. Starting from enantiomerically enriched antiN-diphenylmethyl-3-amino-1,2-diols, and after a change in the nitrogen protecting group, an intramolecular Mitsunobu reaction leads to the erythro aminoalkyl epoxides; a three step sequence consisting of protection of the primary alcohol, activation
An enantioselective, stereodivergent approach to anti- and syn-α-hydroxy-β-amino acids from anti-3-amino-1,2-diols. Synthesis of the ready for coupling taxotere® side chain.
作者:Mireia Pastó、Albert Moyano、Miquel A. Pericàs、Antoni Riera
DOI:10.1016/0957-4166(95)00442-4
日期:1996.1
enantiomeric purity from readily available anti-N-Boc-1-tert-butyldimethylsilyl-3-amino-1,2-diols. The preparation of the anti series is straightforward, and takes place by protection of the secondary hydroxyl group (1-ethoxyethyl) followed by desilylation/oxidation of the primary hydroxyl group. For the preparation of the syn isomers, the secondary alcohol is inverted at the beginning of the sequence by Mitsunobu
Enantioselective synthesis of fully protected anti 3-amino-2-hydroxy butyrates
作者:Mireia Pastó、Albert Moyano、Miquel A. Pericàs、Antoni Riera
DOI:10.1016/0957-4166(95)00309-d
日期:1995.9
An efficient enantioselective synthesis of fully protected anti 3-amino-2hydroxybutyrates has been developed. Starting from enantiomerically enriched anti N-diphenylmethyl-3-amino-1,2-butanediol, after a change in the nitrogen protecting group, the primary alcohol was protected by regioselective reduction of the corresponding p-methoxybenzylidene acetal. Formation of the oxazolidine and deprotection of the primary alcohol followed by oxidation afforded protected alpha-hydroxy-beta-amino acids in good yield. Since the source of asymmetry is a catalytic Sharpless epoxidation, both enantiomeric series are available and the methodology developed here is expected to be of broad applicability.