For the first time, a method for enantiomer resolution of the anticonvulsant Galodif (1-((3-chlorophenyl)(phenyl)methyl) urea) by chiral HPLC was developed, whereas the enantiomeric composition of 1-((3-chlorophenyl)(phenyl)methyl) amine-precursor in Galodif synthesis-cannot be resolved by this method. However, starting 1-((3-chlorophenyl)(phenyl)methyl) amine quantitatively forms diastereomeric N-((3-chlorophenyl)(phenyl)methyl)-1-camphorsulfonamides in reaction with chiral (1R)-(+)- or (1S)-(-)-camphor-10-sulfonyl chlorides. The diastereomeric ratio of obtained camphorsulfonamides can be easily determined by NMR 1 H and 13 C spectroscopy. The DFT calculations of specific rotation of Galodif enantiomers showed good agreement with experimental data. The absolute configuration of enantiomers was proposed for the first time.
Keywords: Galodif; NMR spectroscopy; anticonvulsants; chiral HPLC; chiral analysis; polarimetry; specific rotation calculations.
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