| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1347904 | Tetrahedron: Asymmetry | 2012 | 5 Pages |
A novel strategy for the preparation of β,β′-dihydroxy α,α-disubstituted α-amino acids bearing a sugar moiety has been developed. The procedure is based on two Henry reactions: the first Henry reaction involves a sugar aldehyde and nitroethanol to furnish a sugar derived α-hydroxymethyl α-nitroalkanol while the second Henry reaction is between this nitro sugar and formaldehyde. This sequence provided the expected epimers of sugar derived α,α-dihydroxymethyl α -nitroalkanols, from which the corresponding β,β′-dibenzyloxy α-N-benzyloxycarbonylamino esters were easily obtained. All rights reserved.
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1,5,7-Tri-O-benzyl-6-deoxy-6-C-hydroxymethyl-2,3-di-O-isopropyliden-6-nitro-d-glycero-α-d-manno-heptofuranoseC32H37NO9[α]D25=+20.2 (c 1.4, CHCl3)Source of asymmetry: d-mannoseAbsolute configuration: (1S,2S,3S,4R,5R,6S)
(4R,5R)-4-(Benzyloxymethyl)-4-[5-(1,5-di-O-benzyl-2,3-di-O-isopropyliden-α-d-lyxofuran-5-C-yl)]oxazolidin-2-oneC33H37NO8[α]D23=+2.2 (c 1.0, chloroform)Source of asymmetry: d-mannoseAbsolute configuration: (2S,3S,4S,5R,6R,7R)
1,5,7-Tri-O-benzyl-6-benzyloxycarbonylamino-6-deoxy-6-C-hydroxymethyl-2,3-di-O-isopropyliden-d-glycero-α-d-manno-heptofuranoseC40H45NO9[α]D23=+48.8 (c 1.35, chloroform)Source of asymmetry: d-mannoseAbsolute configuration: (1S,2S,3S,4R,5R,6S)
Methyl 1,5,7-tri-O-benzyl-6-benzyloxycarbonylamino-6-deoxy-6-C-hydroxymethyl-2,3-di-O-isopropyliden-d-glycero-α-d-manno-heptofuranoateC40H45NO10[α]D24=+26.3 (c 0.9, chloroform)Source of asymmetry: d-mannoseAbsolute configuration: (1S,2S,3S,4R,5R,6S)
1,5,7-Tri-O-benzyl-6-deoxy-6-C-hydroxymethyl-2,3-di-O-isopropyliden-6-nitro-l-glycero-α-d-manno-heptofuranoseC32H37NO9[α]D25=+36.7 (c 1.2, CHCl3)Source of asymmetry: d-mannoseAbsolute configuration: (1S,2S,3S,4R,5R,6R)
1,5,7-Tri-O-benzyl-6-benzyloxycarbonylamino-6-deoxy-6-C-hydroxymethyl-2,3-di-O-isopropyliden-l-glycero-α-d-manno-heptofuranoseC40H45NO9[α]D23=+19.1 (c 1.2, CHCl3)Source of asymmetry: d-mannoseAbsolute configuration: (1S,2S,3S,4R,5R,6R)
