Therapeutic agent for treating dysuria (NC‐1800): Absolute configuration of the enantiomers

The absolute configuration of an enantiomer of the title compound, (+/-)-1. fumaric acid salt, was determined by X-ray crystallographic analysis of (+)-1 [salt of (+)-tartaric acid [(+)-2]]. This salt for X-ray crystallographic analysis was prepared by a simple method. The analysis of (+)-1 [salt of (+)-2] showed that this enantiomer has the 5-S and 1-R absolute configuration. The final R and Rw values were 0.0614 and 0.0713, respectively.