Configuration at C‐24 of 24‐methyl and 24‐ethylcholesterol in tracheophytes

Abstract 24‐Ethylcholesterol was shown by proton magnetic resonance spectroscopy to have only the α‐configuration in a series of tracheophytes ranging through the evolutionary hierarchy from ferns through gymnosperms and primitive angiosperms to climax angiosperms. 24‐Methylcholesterol, however, was consistently an epimeric mixture, with the 24α‐epimer present in about twice the concentration of the 24β‐epimer. 24‐Methylcholesterol was always present in smaller amount than the 24‐ethylcholesterol.