Method for identifying modulators of notch signaling

A pharmaceutical composition comprising a compound of formula II:

• where m is an integer selected from 1 to 4;
• W is selected from the group consisting of H, F—, Cl—, Br—and I—;
• R1, R2, R3 and R4 are each independently selected from the group consisting of H, isopropyl, tertbutyl, and (CH2)nCH3;
• the subscript n is an integer independently selected from 0 to 15;
• X is O or NH;
• Y is N;
• Z is NH2,
• a pharmaceutically acceptable carrier.