Hydrated structures of N-methylated cholamide derivatives

The crystal structures of N-methylcholamide quarter-hydrate (N-methyl-3 alpha,7 alpha, 12 alpha-trihydroxy-5 beta-cholan-24-amide 0.25-hydrate, C25H43NO4.0.25H(2)O), recrystallized from acetone by diffusion of water, N-methylcholamide sesquihydrate (N-methyl-3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholan-24-amide 1.5-hydrate, C25H43NO4.1.5H(2)O), recrystallized from a 10:1 ethyl acetate-absolute ethanol solution by slow evaporation, and N,N-dimethylcholamide hemihydrate (N,N-dimethyl-3 alpha,7 alpha, 12 alpha-trihydroxy-5 beta-cholan-24-amide 0.5-hydrate, C26H45NO4.0.5H(2)O), recrystallized from a 1:1 absolute methanolethyl acetate solution by slow evaporation, have been determined. These structures are the first reported crystal structures of both N-methylcholamide and N, N-dimethylcholamide. Each structure contains water molecules that sit on special positions. The N-dimethylcholamide sesquihydrate and N,N-dimethylcholamide hemihydrate forms are isostructural.