Suggested Reaction 1.3.4.-

Left

11beta,17alpha,21-Trihydroxy-4-pregnene-3,20-dione
+1,4-Dithiothreitol

Right

11beta,17alpha,21-Trihydroxy-5beta-pregnane-3,20-dione
+Oxidized dithiothreitol

[BiSSCat | GREP ]