| abstract |
Disclosed is an acid addition salt of 3-(2-cyanophenyl)-5-(2-pyridyl)-1-phenyl-1,2-dihydropyridin-2-one or a hydrate of the acid addition salt, wherein the acid used in the acid addition salt is selected from the group consisting of benzenesulfonic acid, p-toluenesulfonic acid, hydrochloric acid, hydrobromic acid, sulfuric acid, methanesulfonic acid, fumaric acid, tartaric acid, succinic acid, and benzoic acid. |