of the spirostan structure, with its ketone spiro acetal functionality, was fundamental in the development of the Marker degradation, which allowed the industrial production of progesterone and other sex hormones from plant steroids.

Sarsasapogenin is unusual in that it has a cis-linkage between rings A and B of the steroid nucleus, as opposed to the more usual trans-linkage found in other saturated steroids. This 5?