Hydrophilic and hydrophobic pockets at surfaces of strychninium self-assemblies in pseudopolymorphous crystals of strychninium salts

摘要: Racemic mixtures of N-3,5-dinitrobenzoyl-DL-alanine, as well N-4-nitrobenzoyl-DL-glutamic acid were resolved by fractional crystallization strychninium diastereomeric salts. Crystals N-3,5-dinitrobenzoyl-D-alaninate methanol solvate (1), and distrychninium N-4-nitrobenzoyl-D-glutamate tetrahydrate (3) grown during these resolutions. stychninium 3.5 hydrate (2) 4.6 (4) obtained recrystallization 1 3, respectively. Crystal structures 1–4 determined. In all the crystals in most known salts, cations form similar pillars. Depending on how pillars are linked, surfaces resulting self-assemblies reveal various donor/acceptor capabilities. The amide O atom can participate weak (C–H⋯O) or strong (e.g. O–H⋯O) hydrogen bonds. kind bond, strong, components recognized cations. These may be compounds (or other cations) solvent molecules. Comparison crystal brucinium salts (brucine is dimethoxy derivative strychnine) indicates that both self-assemblies. However, alkaloids preferences to differing assemblies. While usually assembled a way allows C–H⋯O bonds, common corrugated monolayer sheets provide an opportunity for e.g. O–H⋯O different show additional possibilities endeavor achieve efficient resolution racemic mixtures.