4-Nitrobenzoic Acid → HCID 69216045, compound

Participants

Reaction Steps

(2S,3S,4R)-6-nitro-4-[N-(4-chlorophenyl)-N-(2-methyl-2H-tetrazol-5-ylmethyl)amino]-3-hydroxy-2-methyl-2-dimethoxymethyl-3,4-dihydro-2H-1-benzopyran (100 mg, 0.20 mmol) was dissolved in the mixed solvent (3.8 ml, toluene/tetrahydrofuran=1/1). Triphenyl phosphine (268 mg, 0.99 mmol) and 4-nitrobenzoic acid (149 mg, 0.87 mmol) were added to the solution at 0° C. Thereafter, diethyl azocarboxylte (156 μl, 0.99 mmol) was slowly added to the reaction through syringe. The reaction mixture was stirred for 3 days at the room temperature. The solvent was removed under reduced pressure to obtain a crude product. The crude product was purified by short silica gel column chromatoghaphy to semi-product. Further purification was not accomplished. The crude product was dissolved in dichloromethane. DIBAL-H (1 M in hexane, 1.36 mmol) was slowly added to the solution dropwise at −20° C. The reaction mixture was stirred for 20 min. To terminate the reaction, the saturated brine solution was added to the reaction mixture. The organic layer was separated. The solvent was removed under reduced pressure to obtain a crude product. The crude product was purified by silica gel column chromatography (developing solvent-n-hexane:ethyl acetate=1:2), to give desired compound (18 mg, yield: 19%).

Provenance & Evidence