Intermediate 15 (Example 23) (0.124 g, 0.439 mmol) was combined with 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) (0.093 g, 0.53 mmol) and diluted with DCM (4 mL). This was immediately treated with 4-methyl morpholine (0.10 mL, 0.88 mmol) and allowed to stir at ambient temperature for 1 h. Intermediate 13 (Example 20) (0.20 g, 0.462 mmol) was then added in one portion. Stirring was continued overnight. After 18 h, reaction solvents were removed and resulting crude solids purified via HPLC to afford the title compound as a white solid (0.1 g, 32%).
