[{"from": "human", "value": "What can you tell me about this molecule? [C][C][Branch1][C][C][Branch1][Ring1][C][#N][C][=C][C][=Branch1][S][=C][C][=Branch1][Ring2][=C][Ring1][=Branch1][C][N][C][=N][C][=N][Ring1][Branch1][C][Branch1][C][C][Branch1][C][C][C][#N]"}, {"from": "gpt", "value": "The molecule is a nonsteroidal inhibitor of estrogen synthesis that resembles paclitaxel in chemical structure.  As a third-generation aromatase inhibitor, anastrozole selectively binds to and reversibly inhibits aromatase, a cytochrome P-450 enzyme complex found in many tissues including those of the premenopausal ovary, liver, and breast; aromatase catalyzes the aromatization of androstenedione and testosterone into estrone and estradiol, the final step in estrogen biosynthesis.  In estrogen-dependent breast cancers, ananstrozole may inhibit tumor growth. (NCI04)"}]