Scheme 1. Reagents and Conditions: (a) CH3NH2 or C6H11NH2, Tetrahydrofuran (THF), Room Temperature (rt), 12 h (35–40% Yield); (b) 2c–5c, CH3COCl, NEt3, CH2Cl2, 0 °C, 2 h (82–99%); (c) LiHMDS, THF, −78 °C, 0.5 h, Then (CH3OCO)2, 0 °C, 4 h (38–95%); (d) LiOH 1 N, MeOH, 40 °C, 2 h (49–100%); and (e) Amine, HBTU, DIEA, Dimethylformamide (DMF), rt, Overnight (26–44%).
