1-Hydroxybenzotriazole → tert-butyl (2R,5S)-2-[(R)-hydroxy(phenyl)methyl]-5-{4-[(1-oxo-2-oxa-8-azaspiro[4.5]dec-8-yl)carbonyl]benzyl)pyrrolidine-1-carboxylate

Participants

Reaction Steps

To a solution of 30 mg (0.07 mmol) 4-({(2S,5R)-1-(tert-butoxycarbonyl)-5-[(R)-hydroxy(phenyl)methyl]pyrrolidin-2-yl}methyl)benzoic acid (i-1) in 1 ml anhydrous DMF at ambient temperature was added 20 mg (0.1 mmol) 2-oxa-8-azaspiro[4.5]decan-1-one, followed by 20 mg (0.1 mmol) EDCl, 15 mg (0.10 mmol) HOBt, and 0.070 ml (0.35 mmol) diisopropylethylamine. The solution was stirred for 2 h. It was then filtered and purified by reverse-phase HPLC (TMC Pro-Pac C18; 35-100% 0.1% trifluoroacetic acid in acetonitrile/0.1% trifluoroacetic acid in water gradient). The pure fractions were lyophilized overnight to give 28 mg (70%) of the title compound as a white solid. LC/MS 549.2 (M+1).

Provenance & Evidence