Reaction Steps
To 3-[3-(hydroxymethyl)cyclopentyl]-3-[4-(7-[2-(trimethylsilyl)ethoxy]methyl-7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl]propanenitrile (60.4 mg, 0.129 mmol) dissolved in CH2Cl2 (2.0 mL) was added TFA (1.0 mL) and the reaction was stirred for 1 hour at which point LCMS indicated complete cleavage to the N-hydroxymethyl intermediate (m/z=367). The trifluoroacetate ester of the hydroxymethyl of the cyclopentyl ring was also observed (m/z=463). The solvent was removed and to the residue was added methanol (1.0 mL) followed by ethylenediamine (80 μL, 1.19 mmol). The resulting mixture was stirred for 16 hours at which point LCMS indicated complete reaction to the desired product. The solvent was removed and the residue was purified by chiral HPLC to provide four distinct diastereomers (20.2 mg total of four isomers, 46%). NOE experiments suggest that all isomers have cis geometry on the cyclopentyl ring. Isomers 1 and 2: 1H NMR (400 MHz, CD3OD): δ 8.65 (s, 1H), 8.62 (s, 1H), 8.38 (s, 1H), 7.50 (d, 1H), 6.95 (d, 1H), 4.51 (m, 1H), 3.40 (m, 2H), 3.22 (m, 1H), 3.11 (m, 1H), 2.61 (m, 1H), 2.10 (m, 1H), 1.94 (m, 1H), 1.82 (m, 1H), 1.6-1.4 (m, 3H), 1.03 (m, 1H). Isomers 3 and 4: 1H NMR (400 MHz, CD3OD): δ 8.66 (s, 1H), 8.62 (s, 1H), 8.37 (s, 1H), 7.50 (d, 1H), 6.95 (d, 1H), 4.51 (m, 1H), 3.46 (m, 2H), 3.21 (m, 1H), 3.11 (m, 1H), 2.61 (m, 1H), 2.22 (m, 1H), 2.09 (m, 1H), 1.71 (m, 1H), 1.55-1.25 (m, 3H), 1.04 (m, 1H). MS (EI) m/z=337.1 (M+H).
