Potassium Carbonate → (R)-tert-Butyl 4-(2-(1-oxa-4,9-diazaspiro[5.5]undecan-9-yl)ethoxy)benzyl(2-hydroxy-2-(4-hydroxy-2-oxo-2,3-dihydrobenzo[d]thiazol-7-yl)ethyl)carbamate

Participants

Reaction Steps

A solution of potassium carbonate (240 mg) in water (35 mL) was added to a solution of (R)-tert-butyl 2-hydroxy-2-(4-hydroxy-2-oxo-2,3-dihydrobenzo[d]thiazol-7-yl)ethyl(4-(2-(4-(2,2,2-trifluoroacetyl)-1-oxa-4,9-diazaspiro[5.5]undecan-9-yl)ethoxy)benzyl)carbamate (examples 223-263, step a) (725 mg) in MeOH (35 mL). The resulting mixture was stirred at RT for 5 h. Methanol was removed by evaporation under a stream of nitrogen keeping the reaction mixture at 25° C. Water (20 mL) and brine (30 mL) were added and the mixture was extracted with ethyl acetate (7×30 mL). The combined organic layers were dried over sodium sulphate, filtered and evaporated in vacuo. The residue was purified by silica gel chromatography eluting with 0-20% (2M NH3 in MeOH)/DCM to give the subtitled compound as a white solid. Yield 385 mg.

Provenance & Evidence