Download full text in PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... The synthesis of new 18- or 18'-thioether derivatives of progesterone are reported, along with acid-catalyzed rearrangements occurring during the thioacetalization reactions. ... Address reprint requests to Dr. Antoinette Viger, Laboratoire de Chimie Organique Biologique, UA CNRS ...