| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1346781 | Tetrahedron: Asymmetry | 2010 | 15 Pages |
The synthesis of a wide range of alkenyl 4,6-O-(S)-benzylidene-β-d-galactopyranosides is described. The cyclopropanation and epoxidation reactions of these compounds were developed. Cyclopropanation reactions took place with high stereoselectivity giving diastereomeric excesses of up to 100%. As a part of our aim in studying hydroxyl-directed reactions, their epoxidation with m-CPBA was carried out. High diastereomeric excesses (80–100%) were obtained when the hydroxyl group at C-2 of the auxiliary was unprotected. The β-d-galactopyranoside moiety constitutes as an interesting auxiliary, due to its efficient chirality transfer capability as well as providing a way to obtain a variety of glycolipid derivatives.
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(E)-3-Phenyl-2-propenyl 4,6-O-(S)-benzylidene-β-d-galactopyranosideC22H24O6Ee = 100%[α]D25=-22.8 (c 0.5, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
(E)-2-Butenyl 4,6-O-(S)-benzylidene-β-d-galactopyranosideC17H22O6Ee = 100%[α]D25=-43.1 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
(E)-2-Decenyl 4,6-O-(S)-benzylidene-β-d-galactopyranosideC23H34O6Ee = 100%[α]D25=-14.6 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-,β-d-galacto
(E)-3-Methyl-2-butenyl 4,6-O-(S)-benzylidene-β-d-galactopyranosideC18H24O6Ee = 100%[α]D25=-26.5 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: 4,6-O-(S)-, β-d-galacto
2-Methyl-2-propenyl 4,6-O-(S)-benzylidene-β-d-galactopyranosideC17H22O6Ee = 100%[α]D25=-21.6 (c 0.8, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: 4,6-O-(S)-, β-d-galacto
(E)-2-Methyl-3-phenyl-2-propenyl 4,6-O-(S)-benzylidene-β-d-galactopyranosideC23H26O6Ee = 100%[α]D25=-27.4 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
(E)-3-Phenyl-2-propenyl 2,3-di-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC36H36O6Ee = 100%[α]D25=-30.3 (c 0.4, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
(E)-2-Butenyl 2,3-di-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC31H34O6Ee = 100%[α]D25=+16.0 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
(E)-2-Decenyl 2,3-di-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC37H46O6Ee = 100%[α]D25=+20.1 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
3-Methyl-2-butenyl 2,3-di-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC32H36O6Ee = 100%[α]D25=-50.3 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: 4,6-O-(S)-, β-d-galacto
2-Methyl-2-propenyl 2,3-di-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC31H34O6Ee = 100%[α]D25=+36.3 (c 0.9, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: 4,6-O-(S)-, β-d-galacto
(E)-2-Methyl-3-phenyl-2-propenyl 2,3-di-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC37H38O6Ee = 100%[α]D25=-27.4 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
(E)-3-Phenyl-2-propenyl 3-O-benzyl-4,6-O-(S)-benzylidene-β-D-galactopyranosideC29H30O6Ee = 100%[α]D25=-35.1 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
(E)-2-Butenyl 3-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC24H28O6Ee = 100%[α]D25=+8.2 (c 0.5, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
(E)-2-Decenyl 3-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC30H40O6Ee = 100%[α]D25=-44.0 (c 0.3, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
3-Methyl-2-butenyl 3-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC25H30O6Ee = 100%[α]D25=+11.0 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: 4,6-O-(S)-, β-d-galacto
2-Methyl-2-propenyl 3-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC24H28O6Ee = 100%[α]D25=+6.2 (c 0.5 CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: 4,6-O-(S)-, β-d-galacto
(E)-2-Methyl-3-phenyl-2-propenyl 3-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC30H32O6Ee = 100%[α]D25=-27.4 (c 1.0, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (E)-, 4,6-O-(S)-, β-d-galacto
(2S,3S)-(2-Phenylcyclopropyl)methyl 3-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC30H32O6De = 100%[α]D25=-22.5 (c 0.8, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (2S,3S)-, 4,6-O-(S)-, β-d-galacto
(2S)-3-Methyl-2,3-methylidenebutyl 3-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC26H32O6De = 100%[α]D25=-56.6 (c 0.3, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (2S)-, 4,6-O-(S)-, β-d-galacto
(2S,3S)-2,3-Methylidenedecyl 3-O-benzyl-4,6-O-(S)-benzylidene-β-d-galactopyranosideC31H42O6De = 100%[α]D25=-27.4 (c 0.5, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (2S,3S)-, 4,6-O-(S)-, β-d-galacto
(1S,2S)-trans-1-Heptyl-2-hydroxymethylcyclopropaneC11H22OEe = 100%[α]D25=+16.8 (c 0.5, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2S)-
(2R)-2,3-Epoxypropyl 4,6-O-(S)-benzylidene-β-d-galactopyranosideC16H20O7De = 100%[α]D25=-31.2 (c 0.5, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (2R)-, 4,6-O-(S)-, β-d-galacto
