Nafoxidine

Nafoxidine (U-11,000A) is a non-steroidal antiestrogenic drug that has been investigated to treat advanced breast cancer. It is structurally related to tamoxifen.
The drug is one of a series of similar structures invented at Upjohn. An earlier compound known as U-11,555 is related to Nafoxidine was found to cause photosensitivity in human volunteers.