The invention relates to novel tetrahydroisoquinoline compounds that are selective estrogen receptor downregulators (SERDs). The present invention also relates to pharmaceutical compositions comprising one or more of the compounds as an active ingredient, and to the use of the compounds in the treatment of estrogen receptor (ER) mediated or dependent diseases or conditions, for example cancer such as breast cancer.本發明涉及作為選擇性雌激素受體下調劑(SERD)的新型四氫異喹啉化合物。本發明還涉及包含作為活性成分的一種或多種所述化合物的藥物組合物,和所述化合物在治療雌激素受體(ER)介導的或依賴性疾病或病況,例如癌症(如乳腺癌)中的用途。