To a solution of 8-(1-azepan-4-ylethoxy)-2-(2-isopropyl-5-methyl-2H-[1,2,4]triazol-3-yl)-4,5-dihydro-6-oxa-1,3a-diazabenzo[e]azulene from Example 10 (50 mg, 0.11 mmol) in a 10:1 mixture of DCM:MeOH (2.2 mL) were added acetone (81 uL, 1.1 mmol), AcOH (0.011 mmol) and sodium triacetoxyborohydride (47 mg, 0.22 mmol). The reaction mixture was stirred for 24 h at RT, then diluted with DCM and poured into water. The aqueous layer was extracted with DCM (×3) and the combined organic phases were washed with brine, then dried (Na2SO4) and concentrated in vacuo. The resulting residue was purified by column chromatography (Si-PCC, gradient 0-10% 2M NH3/MeOH in DCM) affording 217 as a white solid (48 mg, 81%). LCMS: RT 3.16 min [M+H]+ 493.2. 1H NMR (CDCl3, 400 MHz): δ 8.40 (1H, d, J=8.95 Hz), 7.56 (1H, s), 6.71 (1H, d, J=9.07 Hz), 6.52 (1H, s), 5.98-5.86 (1H, m), 4.52-4.44 (2H, m), 4.43-4.36 (2H, m), 4.33-4.23 (1H, m), 2.92-2.80 (1H, m), 2.76-2.48 (5H, m), 2.41 (3H, s), 2.02-1.74 (5H, m), 1.63-1.40 (7H, m), 1.30-1.23 (3H, m), 1.03-0.95 (6H, m)
