Solid-State Structure of Orphenadrine Hydrochloride and Conformational Comparisons with Diphenhydramine Hydrochloride and nefopam hydrochloride

Intramolecular interactions contributing for the conformational preference of bioactive diphenhydramine: Manifestation of the gauche effect

“…This theoretical level includes dispersion effects and has shown good agreement with CCSD results for aromatic systems [24]. The gauche effect is evident for 1 after analyzing the energy results of Table 1 (in agreement with solid-state data available in the literature [25]), where only a single high energy conformer (two in solution) appears with anti geometry along with the O-C-C-N torsional angle. Indeed, the remaining gauche conformers are more stable than anti ones independent of the medium, despite diphenhydramine hydrochloride is supposed to have different conformation in crystals and solutions [26].…”

Doxylamine hydrogen succinate

“…diphenhydramine hydrochloride (Glaser & Maartmann-Moe, 1990), diphenhydramine thiourea complex (Wiedenfeld & Knoch, 1987), carbinoxamine maleate (Bertolasi et al, 1980) and clemastine hydrogen fumarate (Parvez & Wendling, 1991). The crystal structure of orphenadrine hydrochloride, a skeletal muscle relaxant, which is closely related to these compounds has also been reported (Glaser et al, 1992). Continuing our investigations on the conformation of this important antiallergic drug, we now report the crystal structure of doxylamine hydrogen succinate, (I).…”

Orphenadrinium picrate picric acid

“…Clinical and pharmacological review of the efficacy of orphenadrine and its combination with paracetamol has been described (Hunskaar & Donnel, 1991). The solid-state structure of orphenadrine hydrochloride and conformational comparisons with diphenhydramine hydrochloride and nefopam hydrochloride was reported (Glaser et al, 1992). The present work reports the crystal structure of the title compound which was obtained by the interaction between orphenadrine hydrochloride and 2,4,6-trinitrophenol in aqueous medium.…”

“…For the efficiency of the anticholinergic drug orphenadrine (systematic name N,N-dimethyl-2-[(2-methylphenyl)phenylmethoxy]ethanamine), see: Hunskaar & Donnel (1991). For related structures, see: Glaser et al (1992); Yathirajan et al (2007). For details of hydrogen bonding, see: Jeffrey & Saenger (1991); Jeffrey (1997); Scheiner (1997).…”