Imidazole → (S)-tert-Butyl 2-((S)-1-amino-3-(4-(3-(2-(tert-butyldimethylsilyloxy)ethyl)-2-oxo-2,3-dihydrobenzo[d]thiazol-6-yl)phenyl)-1-oxopropan-2-ylcarbamoyl)piperidine-1-carboxylate

Participants

Reaction Steps

A solution of (S)-tert-butyl 2-((S)-1-amino-3-(4-(3-(2-hydroxyethyl)-2-oxo-2,3-dihydrobenzo[d]thiazol-6-yl)phenyl)-1-oxopropan-2-ylcarbamoyl)piperidine-1-carboxylate (138 mg), tert-butyldimethylsilyl chloride (40.2 mg) and imidazole (41.3 mg) in DMF (1 mL) was stirred for 16 h. Further tert-butyldimethylsilyl chloride (40.2 mg) and imidazole (41.3 mg) were added and stirred for 4 h. Water was added and the mixture was extracted thrice with ethyl acetate. The organic layers were washed twice with water, combined, dried over magnesium sulfate, evaporated and purified by flash silica chromatography eluting with 1:2 acetone/isohexane to give the subtitle compound (130 mg) as a colourless gum.

Provenance & Evidence