tert-Butyl 4-carbamoyl-3-methoxy-imino-4-methyl-piperidine-1-carboxyl-ate.

The title compound, C(13)H(23)N(3)O(4), was prepared starting from ethyl N-benzyl-3-oxopiperidine-4-carboxyl-ate through a nine-step reaction, including hydrogenation, Boc (tert-butoxy-carbon-yl) protection, methyl-ation, oximation, hydrolysis, esterification and ammonolysis. In the crystal structure, mol-ecules are linked by inter-molecular N-H⋯O hydrogen bonds to form a porous three-dimensional network with solvent-free hydro-phobic channels extending along the c axis.