10.1016/0039-128X(81)90038-6
The research focuses on the total synthesis of 12,15-bisthia-1,3,5(10),6,8,13(14)-gonahexaen-17-one (III), a heterocyclic steroid compound. The study aims to explore the influence of sulfur at position '12' of the steroid nucleus on biological activity, building on previous work on 3-deoxy-12-thiaequilenin and 12-thiaequilenin methyl ether. The synthesis involves a series of chemical reactions starting with 1-chloromethylnaphthalene (IV), which is treated with thioglycollic acid in sodium hydroxide to form l-naphthylmethyl-thioacetic acid (V). This compound is then cyclodehydrated with phosphorus pentoxide to yield 1-oxo-3-thia-1,2,3,4-tetrahydrophenanthrene (VI). Further reactions with thioglycollic acid and p-toluenesulfonic acid (PTS) lead to the formation of (3-thia-3,4-dihydrophenanthren-1-yl)thioacetic acid (VII), which is cyclodehydrated again to obtain the target compound (III).