Sodium → 2-(2-Methoxycarbonylethylthio)ethyl beta-D-galactopyranoside

HRID 653329Notes

Reaction equation

HRID 653329 reaction equation
C([O:4][C@@H:5]1[C@@H:20]([O:21]C(=O)C)[C@@H:19]([O:25]C(=O)C)[C@@H:18]([CH2:29][O:30]C(=O)C)[O:17][C@H:6]1[O:7][CH2:8][CH2:9][S:10][CH2:11][CH2:12][C:13]([O:15][CH3:16])=[O:14])(=O)C.C[O-].[Na+].[Na]>CO>[O:7]([CH2:8][CH2:9][S:10][CH2:11][CH2:12][C:13]([O:15][CH3:16])=[O:14])[C@@H:6]1[O:17][C@H:18]([CH2:29][OH:30])[C@H:19]([OH:25])[C@H:20]([OH:21])[C@H:5]1[OH:4]

Participants

5

Reactant 3

HCID 5360545SodiumHCID 10942334Sodium MethoxideHCID 542695972-(2-Methoxycarbonylethylthio)ethyl 2,3,4,6-tetra-O-acetyl-beta-D-galactopyranoside

Product 1

HCID 541048612-(2-Methoxycarbonylethylthio)ethyl beta-D-galactopyranosideYield 77.9%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent3×

Procedure

2-(2-Methoxycarbonylethylthio)ethyl 2,3,4,6-tetra-O-acetyl-β-D-galactopyranoside (19) (1.00 g; 2.32 mmol) was dissolved in 25 ml of dry methanol and added to a solution of sodium methoxide in methanol, prepared from sodium (~0.05 g) and 10 ml of methanol. Stirring was continued for 4 h after which the reaction mixture was neutralized with Duolite-H+ (methanol washed and dried). Filtration and evaporation of the solvent gave a quantitative yield of the title compound (28; 590 mg) which was pure according to TLC (SiO2, chloroform/methanol/water 65:35:10) and NMR (D2O, TMS as an external standard): δ 4.44 (d, 1H, J1,2 =7.62 Hz, H1), 4.08 (m, 1H, OCH2 --CH2), 3.72 (s, 3H, OCH3), 3.52 (dd, 1H, H2), 2.92-2.70 (m, 6H, CH2S, CH2CO) 13C-NMR (D2O, TMS as an external standard) δ 178.2 (CO), 105.8 (C-1), 78.1, 75.6, 73.6, 71.5 (C2-C5), 71.7 (C-6), 63.8 (O--CH2 of aglycon) 55.2 (OCH3), 37.1, 33.7, 29.3 (--CH2 of aglycon).

Workup

  1. filtrationFiltration and evaporation of the solvent

Sources & evidence

ORD record
ord-76bf985513aa44a39b4b98b9a0534423
Source dataset
uspto-grants-1987_06
Patent number
US04675392

Reaction notes

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