Cesium fluoride → HCID 67197146, compound

Participants

Reaction Steps

A mixture of 3-(5-bromothiophen-2-yl-methyl)-4-methyl-1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)indole obtained in Example 45-(3) (190 mg), thiophene-2-boronic acid (229 mg), cesium fluoride (272 mg) and tetrakis(triphenylphosphine)-palladium(0) (34.5 mg) in 1,2-dimethoxyethane (6 ml) was refluxed for 6 hours under argon atmosphere. The reaction mixture was diluted with ethyl acetate and a saturated aqueous sodium hydrogen carbonate solution, and the organic layer was filtered through an aminosilane-treated silica gel pad. The filtrate was evaporated under reduced pressure to give crude 4-methyl-3-(5-(2-thienyl)-thiophen-2-yl-methyl)-1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)indole, which was partially deacetylated. This crude compound was dissolved in chloroform (6 ml), and thereto were added successively pyridine (0.121 ml), acetic anhydride (0.141 ml) and 4-(dimethylamino)pyridine (3.7 mg). After being stirred at room temperature for 4 hour, the solvent was evaporated under reduced pressure. The residue was dissolved in ethyl acetate (80 ml), and the mixture was washed with a 10% aqueous copper (II) sulfate solution (5 ml) twice and a saturated aqueous sodium hydrogen carbonate solution (5 ml), and dried over magnesium sulfate. The insoluble materials were filtered off, and the filtrate was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=90:10-50:50) to give 4-methyl-3-(5-(2-thienyl)thiophen-2-yl-methyl)-1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)indole (134 mg) as a yellow powder. APCI-Mass m/Z 657 (M+NH4).

Provenance & Evidence