A crystal of a compound represented by general formula (I) (wherein R1 represents a hydrogen atom or a hydroxyl group, and R represents a 2-(trifluoromethyl)pyrimidin-5-yl group or a 5-(trifluoromethyl)pyrazin-2-yl group) or a pharmacologically acceptable salt thereof, which has excellent LCAT activating activity and is useful as an active ingredient for a therapeutic agent or prophylactic agent for arteriosclerosis, arteriosclerotic heart diseases, coronary heart diseases (including heart failure, myocardial infarction, angina pectoris, cardiac ischemia, cardiovascular disorders and angioplasty restenosis), cerebrovascular diseases (including cerebral apoplexy and cerebral infarction), peripheral vascular diseases (including diabetic vascular complications), dyslipidemia, low-HDL cholesterolemia or kidney diseases, especially as an active ingredient for an anti-arteriosclerotic agent.一種通式(I)所示之化合物或其藥理容許鹽之結晶，其具有優異的LCAT活化作用，且可用作動脈硬化症、動脈硬化性心臟病、冠狀動脈性心臟病(包含心臟衰竭、心肌梗塞、心絞痛、心臟缺血、心血管障礙及血管形成性再狹窄)、腦血管疾病(包含腦中風及腦梗塞)、末梢血管疾病(包含糖尿病血管併發症)、血脂異常症、低HDL膽固醇血症、或腎疾病之治療劑或預防劑之有效成分，尤其是抗動脈硬化劑之有效成分。[式中，R1為氫原子或羥基，R為2-(三氟甲基)嘧啶-5-基或5-(三氟甲基)吡-2-基。]
