Fig. 1

The figure shows the human aromatase ligands, including (A) the co-crystalized ligand and androgen precursor androstenedione (A1), (B) type I inhibitors such as exemestane (third generation) (B2) and formestane (second generation) (B2), and (C), type II inhibitors aminoglutethimide (first generation) (C1), fadrozole (third generation) (C2), and the triazoles: vorozole (third generation) (C3), letrozole (third generation) (C4), and anastrozole (third generation (C5)