Trifluoroacetic acid → 2-(6-fluoro-3-methanesulfonyl-imidazo[1,5-a]pyridin-1-yl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid [(R)-2-(3-cyano-azetidin-1-yl)-1-methyl-2-oxo-ethyl]-amide

Participants

Reaction Steps

In a round-bottomed flask, 2-(6-fluoro-3-methanesulfonyl-imidazo[1,5-a]pyridin-1-yl)-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid [(R)-2-(3-cyano-azetidin-1-yl)-1-methyl-2-oxo-ethyl]-amide (0.024 g, 37.5 μmol, Eq: 1.00) was dissolved in dichloromethane (0.3 ml) and trifluoroacetic acid (0.12 ml, 1.6 mmol) was added. The reaction mixture was stirred at room temperature for 2.5 h then concentrated. The residue was redissolved in dichloromethane/methanol/ammonium hydroxide (60:10:1) (3.5 ml). The solution was stirred at room temperature overnight then concentrated. The residue was absorbed on silica gel and chromatographed with MeOH/CH2Cl2/0.5% NH4OH (gradient 0-7% MeOH) to afford 6 mg (30%) of 2-(6-fluoro-3-methanesulfonyl-imidazo[1,5-a]pyridin-1-yl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid [(R)-2-(3-cyano-azetidin-1-yl)-1-methyl-2-oxo-ethyl]-amide as a yellow solid. MS: (M+H)+=511; 1H NMR (DMSO-d6, 300 MHz): δ (ppm) 12.92 (br. s., 1H), 9.17 (s, 1H), 9.01-9.10 (m, 1H), 8.95 (d, J=3.0 Hz, 1H), 8.47-8.53 (m, 1H), 8.42 (d, J=7.6 Hz, 1H), 7.43-7.53 (m, 1H), 4.51-4.80 (m, 3H), 4.27 (q, J=9.6 Hz, 1H), 4.11-4.21 (m, 1H), 3.81-3.94 (m, 1H), 3.57 (s, 3H), 1.40 (t, J=6.4 Hz, 3H).

Provenance & Evidence