Some of the androgen preparations available for clinical use, classified into three types.
Type A derivatives are esterified in the 17b-position; type B steroids have alkyl groups in a 17a-position; and type C derivatives include a variety of additional alterations of ring structure that enhance activity or impede catabolism, or influence both functions. Most androgen preparations involve combinations of type AC or type BC changes. Modified from JE Griffin and JD Wilson ( 1991 ) by courtesy of WB Saunders.
