Reaction Steps
To a mixture of QC-16 (201 mg, 0.42 mmol) in N,N-dimethylformamide (3 mL) was added sodium azide (546 mg, 8.40 mmol, 20 equiv). The mixture was heated at 110° C. with stirring for 2 h. The reaction mixture was cooled to room temperature, diluted with H2O, extracted with EtOAc (3×), and the combined organic extracts were washed sequentially with a saturated aqueous solution of Na2CO3, and H2O, and then dried (Na2SO4). The solution was concentrated and the golden oily residue purified by flash column chromatography on silica gel (EtOAc) to give the free base as an oil (Rf=0.29, EtOAc). High-vacuum drying left 121 mg (0.35 mmol, 83%) of QC-112 as a colorless oil: [α]D24=+6.6° (c=0.7, CDCl3); 1H NMR (400 MHz, CDCl3): δ 1.90-2.05 (m, 2H), 2.66-2.81 (m, 2H), 3.20 (dd, J=13.2, 5.2 Hz, 1H), 3.39 (dd, J=13.2, 4.0 Hz, 1H), 3.44-3.51 (m, 1H), 3.64 (t, J=8.0 Hz, 1H), 3.78 (dd, J=8.0, 6.4 Hz, 1H), 4.02 (s, 2H), 6.98 (br s, 1H), 7.05 (br s, 1H), 7.12 (d, J=8.4 Hz, 2H), 7.25 (d, J=8.4 Hz, 2H), 7.49 (br s, 1H); 13C NMR (100 MHz, CDCl3): δ 29.0, 38.7, 51.8, 53.0, 67.9, 76.1, 109.9, 120.9, 128.8, 129.3, 129.8, 132.1, 138.7, 139.6; HRMS (EI) [M+H]+ Calcd. for C16H19ClN5O2: 348.1227. Found: 348.1234.
