Stereoselective synthesis of β, ε-dihydroxy-α-amino acids by ring opening of 4, 5-dihydroisoxazolyl derivatives

G Cremonesi, P Dalla Croce, F Fontana, C Fiorelli…

Index: Cremonesi, Giuseppe; Croce, Piero Dalla; Fontana, Francesco; Fiorelli, Claudio; Rosa, Concetta La Tetrahedron Asymmetry, 2008 , vol. 19, # 24 p. 2850 - 2855

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Citation Number: 18

Abstract

Enantiomerically pure β-(4, 5-dihydroisoxazol-3-yl)-substituted β-hydroxy-α-amino acids were synthesised stereoselectively by means of an addition reaction between (5, 5- disubstituted-4, 5-dihydroisoxazol-3-yl)-carbaldehydes and (R)-(+)-2, 5-dihydro-3, 6- dimethoxy-2-isopropylpyrazine (Schöllkopf's reagent) as a chiral auxiliary. The addition gave mixtures of only two adducts with high diastereoselectivity. The steric configuration of ...