A solution of the product of Example 12B (0.45 g, 0.79 mmol) in formaldehyde (2 mL, 72.6 mmol) and formic acid (4 mL, 104 mmol) was warmed to 100° C. and was allowed to stir for 2 h then was cooled to ambient temperature and was concentrated under reduced pressure. The mixture was purified via column chromatography (SiO2, 100% CH2Cl2 to 9:1:0.1 CH2Cl2:CH3OH:NH4OH). The free amine was dissolved in EtOAc (1 mL) and p-toluenesulfonic acid-H2O (1 eq) in EtOAc (1 mL) was added. The p-toluenesulfonic acid salt of the title compound (0.25 g, 0.38 mmol, 48% yield) was isolated via filtration. 1H NMR (300 MHz, CD3OD) δ ppm 0.98 (dd, J=6.6, 2.2 Hz, 6H), 1.39 (s, 9H), 2.27-2.34 (m, 1H), 2.36 (s, 3H), 2.55-2.76 (m, 2H), 3.06 (s, 3H), 3.98-4.18 (m, 3H), 4.26-4.37 (m, 1H), 4.50 (d, J=3.4 Hz, 2H), 4.73-4.80 (m, 1H), 7.19-7.26 (m, 3H), 7.34 (d, J=8.8 Hz, 1H), 7.67-7.73 (m, 2H), 7.79 (dd, J=8.8, 2.0 Hz, 1H), 8.39 (d, J=2.0 Hz, 1H); MS (DCI/NH3) m/z 484 (M+H)+. Anal. calculated for C24H32F3N3O2S.C7H8O3S.0.2H2O: Calc: C, 56.47; H, 6.18; N, 6.37. Found: C, 56.19; H, 6.28; N, 6.38.
