An economical semisynthesis of progesterone from the plant steroid diosgenin isolated from yams was developed by Russell Marker in 1940 for the Parke-Davis pharmaceutical company. This synthesis is known as the Marker degradation. class=skin-invert-image|thumb|center|upright=3.65|The Marker semisynthesis of progesterone from diosgenin.
An economical semisynthesis of progesterone from the plant steroid diosgenin isolated from yams was developed by Russell Marker in 1940 for the Parke-Davis pharmaceutical company This synthesis is known as the Marker degradation class=skin-invert-image|thumb|center|upright=365|The Marker semisynthesis of progesterone from diosgenin