Chemical entities of Formula (I):Formula (I), Including enantiomers thereof, wherein R1has any of the values described herein, and compositions comprising such chemical entities； their preparation； and their use in various methods, including the treatment of depression, pain, cognitive disorders, neurodegenerative disorders, and other neurological and peripheral disorders.本發明係關於式(I)之化學實體：式(I)， 包括其對映異構體，其中R1具有本文所述之值中的任一者，及包含該等化學實體之組合物；其製備；及其在各種方法中之用途，包括治療抑鬱症、疼痛、認知障礙、神經退化性病症及其他神經及周邊病症。
