[{"from": "human", "value": "What can you tell me about this molecule? [C][C][/C][=Branch2][Ring1][O][=C][Branch1][=Branch2][\\C][=C][C][=C][C][=C][Ring1][=Branch1][/C][=C][C][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][O][C][C][N][C][/C][=C][C][=C][C][=C][Ring1][=Branch1]"}, {"from": "gpt", "value": "The molecule is a main metabolite of the selective estrogen receptor modulator tamoxifen with anti-estrogen activity. N-desmethyltamoxifen blocks estrogen from binding to the estrogen receptor. This may inhibit estrogen-associated signaling and tumor growth in estrogen-positive tumor cells. Conversion of N-desmethyltamoxifen from tamoxifen is catalyzed by cytochrome P-450 enzymes 3A4 and 3A5. N-desmethyltamoxifen is further hydroxylated, mainly by CYP2D6, to endoxifen, the major clinically active metabolite of tamoxifen."}]