Glucuronide and sulfate conjugates of ICI 182,780, a pure anti-estrogenic steroid. Order of addition, catalysis and substitution effects in glucuronidation

The 3-sulfate 4 and 3- and 17-glucuronide conjugates 5 and 6 of the pure anti-estrogenic steroid ICI 182,780 1, which is expected to be an effective agent for the treatment of breast cancer, have been prepared. The synthesis of 6 could only be satisfactorily achieved using an inverse addition technique, not previously employed in the glucuronic acid series: the value of this technique for some other aglycones is discussed.