Norhyodeoxycholic acid (NHDCA) is a synthetic bile acid and a derivative of hyodeoxycholic acid .1,2 NHDCA is an intermediate in the synthesis of 3β-sulfooxy-7β-hydroxy-24-nor-5-cholen-23-oic acid, which has been used as an internal standard for the quantification of δ5-bile acid conjugates that have been identified in patients with Niemann-Pick disease type C1.3

|1. Schteingart, C.D., and Hofmann, A.F. Synthesis of 24-nor-5β-cholan-23-oic acid derivatives: A convenient and efficient one-carbon degradation of the side chain of natural bile acids. J. Lipid Res. 29(10), 1387-1395 (1988).|2. Une, M., and Hoshita, T. Natural occurrence and chemical synthesis of bile alcohols, higher bile acids, and short side chain bile acids. Hiroshima J. Med. Sci. 43(2), 37-67 (1994).|3. Kakiyama, G., Muto, A., Shimada, M., et al. Chemical synthesis of 3β-sulfooxy-7β-hydroxy-24-nor-5-cholenoic acid: An internal standard for mass spectrometric analysis of the abnormal δ5-bile acids occurring in Niemann-Pick disease. Steroids 74(9), 766-772 (2009).