In-vivo racemization of thalidomide

In 1961, thalidomide was first introduced as an over-the-counter cure for morning sickness. Pregnant women across the country began to take the drug, which worked well, but shortly after, babies began to be born with severe birth defects. Experts linked this to thalidomide and later discovered that the r-enantiomer, which was the cure for morning sickness, underwent a certain reaction (or reactions) within the body that could change its configuration to that of the s-enantiomer. Does anyone know the steps of this reaction or at least what it is called?
[![enter image description here](https://i.stack.imgur.com/Rapil.gif)](https://i.stack.imgur.com/Rapil.gif)


