tamoxifen drug standard solution;tamoxifen free base;Genox;Kessar;Nolvadex;Nolvadex-D;Tamoxen;Tamoxifen;(Z)-2-[4-(1,2-diphenyl-1-butenyl)phenoxy]-N,N-dimethylethanamine;2-[4-[(Z)-1,2-diphenylbut-1-enyl]phenoxy]-N,N-dimethylethanamine;Tamoxifen ( ICI-46474Open