Two epimeric 3-amino-5α-cholestane-3-carboxylic acids were synthesized by both the Strecker method and the Bucherer-hydantoin synthesis as shown in Chart 1. The configurations of these amino acids were established by comparing the hydrolysis rate of their methyl esters. Additionally, their configurations were also supported by some other data such as the pKa' values, mass spectra, and infrared spectra of their derivatives.
