THE HORMONE OF PREPARATION 



learn this (if they can) by making up similar but definitely 

 different substances until they find the simplest substance that 

 has the same action. E. C. Dodds of the Courtauld Institute 

 of Biochemistry, Middlesex Hospital, London, and his fellow 

 workers have thus found a long series of synthetic estrogens, 

 of which the most important is diethyl stilbestrol: 



oicTHn.$ricicsTiiOL 



This compound is practically identical in its effects with 

 the naturally occurring estrogens and is being tried by physi- 

 cians in place of them. Students of chemistry will be interested 

 in the fact brought out by Dodds, that the formula of diethyl 

 stilbestrol can be written so that it resembles, in spatial 

 relations, the formula of estrone and the other natural estro- 

 gens. 



fxy 



DIETHYLSTILBESTROL 



The outstanding difference is that in stilbestrol two of the 

 rings are open. Dodds compares this sort of similarity to 

 that of a particular key, made for a given lock, with the 

 skeleton key which will also open it. When, however, the 

 molecules of diethyl stilbestrol and estrone are represented by 

 3-dimensional models, as was kindly done for me in connection 

 with the Vanuxem Lectures, by Mr. MuUer of the Princeton 

 Chemistry Department under the direction of Professor Hugh 

 Taylor, they do not show the same degree of similarity as do 

 the two diagrams on paper. The relation between the chem- 

 ical structure and the action of these substances can hardly, 

 therefore, be explained by a hypothesis as simple as that sug- 

 gested by Dodds. All we can say is that all the estrogens thus 

 far known, both natural and synthetic, have a ring structure 



{ 89 } 



