(3R, 4S) -7-hydroxymethyl-2,2,9-trimethyl-4- (phenethylamino) -3,4-dihydro-2H-pyrano [2,3- g] quinolin-3-ol and a process for preparing the same. (3R, 4S) -7-hydroxymethyl-2,2,9-trimethyl-4- (phenethylamino) -3,4-dihydro-2H- A process for crystallizing quinolin-3-ol from an acetic acid ester solvent, an aliphatic hydrocarbon solvent, a nitrile solvent, an aromatic hydrocarbon solvent, a ketone solvent or an ether solvent,[과제] 의약품으로서 우수한 (3R,4S)-7-하이드록시메틸-2,2,9-트리메틸-4-(페네틸아미노)-3,4-디하이드로-2H-피라노[2,3-g]퀴놀린-3-올의 결정형태 및 그 제조방법을 제공한다. [해결수단] (3R,4S)-7-하이드록시메틸-2,2,9-트리메틸-4-(페네틸아미노)-3,4-디하이드로-2H-피라노[2,3-g]퀴놀린-3-올을 아세트산 에스테르용매, 지방족 탄화수소용매, 니트릴용매, 방향족 탄화수소용매, 케톤용매, 에테르용매로부터 결정화시키는 제조방법 및 그 결과가 얻어지는 결정형태.
