Cholic acid has been elaborated into a carbamate-based tripodal architecture, which is able to promote an asymmetric organic transformation inside its chiral cavity. The nature of this steroidal catalyst has been disclosed by quantum-chemical calculations. It comprises the preorganization and confinement of the reagents within the cavity of the steroid to form a supramolecular complex held together by means of cooperative H-bond contacts. This operational mode resembles that of some enzymes.