Scheme 1. Synthesis of diaminoquinazolines in Tables 1 and 2. Reagents and conditions: (a) various amines, Et₃N (or DIEA), THF (or DMF), RT, 18–24 h; (b) various amines (5–10 equiv.), microwave, toluene (or neat), 130–185 °C, 30–50 min or i-PrOH, 4 M HCl/dioxane, microwave, 160 °C, 15 min.