Reaction Steps
To a solution of [2-(1,1-dioxido-2,3-dihydro-1,4-benzothiazepin-4(5H)-yl)-6-methyl-N-(pyrrolidin-3-yl)quinolin-4-amine (21 mg, 0.05 mmol, prepared in analogy to Example 21-4) and oxetan-3-one (7.2 mg, 0.10 mmol) in tetrahydrofuran (2 mL) was added acetic acid (8.6 μL, 0.15 mmol). After the mixture being stirred at 55° C. for 1 hour, sodium triacetoxyborohydride (21 mg, 0.10 mmol) was added to the mixture. After being stirred for 2 hours at 65° C., the reaction mixture was concentrated in vacuo. The residue was portioned between ethyl acetate and a saturated aqueous solution of sodium carbonate. The separated organic layer was washed with water, dried over sodium sulfate, and concentrated in vacuo. The residue was purified by preparative HPLC to afford 10 mg of the product as a white solid. MS obsd. (ESI+) [(M+H)+] 479, 1H NMR (400 MHz, CD3OD) δ ppm 8.30 (d, J=1.9 Hz, 1 H), 7.84 (d, J=1.8 Hz, 1 H), 7.78 (s, 1 H), 7.68-7.64 (t, J=3.7 Hz, 1 H), 7.53-7.49 (t, J=3.7 Hz, 2 H), 7.39 (d, J=1.7 Hz, 1 H), 5.98 (s, 1 H), 5.20 (s, 2 H), 4.83-4.78 (m, J=4.7 Hz, 2 H), 4.69-4.60 (m, J=8.4 Hz, 2 H), 4.55 (brs, 2 H), 4.37 (s, 1 H), 3.80-3.74 (m, J=4.1 Hz, 1 H), 3.65-3.61 (m, J=4.2 Hz, 2 H), 2.96-2.89 (m, J=6.6 Hz, 2 H), 2.75-2.72 (m, J=3.3 Hz, 1 H), 2.63-2.47 (m, J=15.9 Hz, 2 H), 2.45 (s, 3 H), 1.95 (m, 1 H).
