Pachysandra alkaloids. IV. Structure of pachysamine-A and -B

(S,E)-N-Methyl-4-[(S)2,6,6-trimethyl-4-oxocyclo-hex-2-en-yl]but-3-en-2-aminium chloride

The title compound, C₁₄H₂₄NO⁺·Cl⁻, crystallizes with four independent mol­ecules in the asymmetric unit. It was isolated from plant Pachysandra terminalis Siebold & Zucc. The six-membered ring has a conformation close to an envelope. In the crystal, N—H⋯Cl hydrogen-bonding inter­actions exist between secondary ammonium groups and free chloride anions, resulting in a one-dimensional supra­molecular structure oriented along [100]. The crystal studied was found to be a two-component non-merohedral twin with twin law [00/00/101], the fractional contribution of the minor component being approximately 33%.