Enantioselective synthesis of (S)- and (R)-α-methylserines: application to the synthesis of (S)- and (R)-N-Boc-N,O-isopropylidene-α-methylserinals
摘要:
This report describes the synthesis of enantiomerically pure (S)- and (R)-alpha -methylserines on a multigram scale, starting from the Weinreb amide of 2-methyl-2-propenoic acid and using a stereodivergent synthetic route that involves a Sharpless asymmetric dihydroxylation reaction. As a synthetic application of these quaternary alpha -amino acids, they were used as starting materials in the synthesis of the well-known valuable homochiral (S)- and (R)-N-Boc-N,O-isopropylidene-alpha -methylserinal building blocks. (C) 2001 Elsevier Science Ltd. All rights reserved.
Understanding the Unusual Regioselectivity in the Nucleophilic Ring-Opening Reactions of <i>g</i><i>em</i>-Disubstituted Cyclic Sulfates. Experimental and Theoretical Studies
作者:Alberto Avenoza、Jesús H. Busto、Francisco Corzana、José I. García、Jesús M. Peregrina
DOI:10.1021/jo034178q
日期:2003.5.1
The regioselectivity of the nucleophilic ring-openingreactions of three gem-disubstituted cyclic sulfates with sodium azide has been studied from both experimental and theoretical viewpoints. It is found that, depending on the substituent present in the cyclic sulfate, the reaction displays reversed regioselectivity, which allows one or another regioisomer to be obtained with selectivities greater
Enantioselective Synthesis of α-Methyl-<scp>d</scp>-cysteine and Lanthionine Building Blocks via α-Methyl-<scp>d</scp>-serine-β-lactone
作者:Nicole D. Smith、Murray Goodman
DOI:10.1021/ol034025p
日期:2003.4.1
[GRAPHICS]We report here the enantioselective synthesis of Boc-alpha-methyl-D-cysteine(PMB)-OH and lanthionine building blocks through the regloselective ring opening of key intermediate Boc-alpha-methyl-D-serine-beta-lactone.
A synthesis of optically active α-quaternary α-amino acids and esters by assembling three components, ketones, (R)-chloromethyl p-tolyl sulfoxide, and sodium azide, via sulfinyloxiranes
yields. The oxidation of the azido aldehydes with iodine in methanol in the presence of KOH followed by the catalytic hydrogenation resulted in α-quaternary α-amino acid methyl esters in good yields. When these reactions were carried out starting from unsymmetrical ketones and optically pure (R)-chloromethyl p-tolyl sulfoxide, a new method for a synthesis of optically active α-quaternary α-amino acids
Enantioselective synthesis of (S)- and (R)-α-methylserines: application to the synthesis of (S)- and (R)-N-Boc-N,O-isopropylidene-α-methylserinals
作者:Alberto Avenoza、Carlos Cativiela、Francisco Corzana、Jesús M. Peregrina、David Sucunza、Marı́a M. Zurbano
DOI:10.1016/s0957-4166(01)00159-8
日期:2001.4
This report describes the synthesis of enantiomerically pure (S)- and (R)-alpha -methylserines on a multigram scale, starting from the Weinreb amide of 2-methyl-2-propenoic acid and using a stereodivergent synthetic route that involves a Sharpless asymmetric dihydroxylation reaction. As a synthetic application of these quaternary alpha -amino acids, they were used as starting materials in the synthesis of the well-known valuable homochiral (S)- and (R)-N-Boc-N,O-isopropylidene-alpha -methylserinal building blocks. (C) 2001 Elsevier Science Ltd. All rights reserved.