A range of tamoxifen derivatives substituted in the 4-position of the 1-phenyl ring are described. The key steps in the synthesis of I-iOdO-, 4-bromo-, and 4-(methy1thio) tamoxifen were reactions of 1, 2-diarylbutanones with the (4-halogenopheny1) lithium or [4- (methy1thio) phenyllmagnesium bromide. Oxidized precursors of 4-(methylthio) tamoxifen were used to prepare the methylsulfinyl and methylsulfonyl derivatives. Further derivatives ...