Hydrated Structures of N-Methylated Cholamide Derivatives

The crystal structures of N-methylcholamide quarterhydrate (N-methyl-3α,7α,12α-trihydroxy-5β-cholan-24-amide 0.25-hydrate, C₂₅H₄₃NO₄.0.25H₂O) recrystallized from acetone by diffusion of water, N-methylcholamide sesquihydrate (N-methyl-3α,7α,12α-trihydroxy-5β-cholan-24-amide 1.5-hydrate, C₂₅H₄₃NO₄.1.5H₂O), recrystallized from a 10:1 ethyl acetate-absolute ethanol solution by slow evaporation, and N,N-dimethylcholamide hemihydrate (N,N-dimethyl-3α,7α,12α-trihydroxy-5β-cholan-24-amide 0.5-hydrate, C₂₆H₄₅NO₄.0.5H₂O) 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-methylcholamide sesquihydrate and N,N-dimethylcholamide hemihydrate forms are isostructural.

-1