Radioactive tyrosine derivative, method for producing same, labeling agent for positron imaging and medical agent for assessing grade of malignancy of tumor respectively composed of radioactive tyrosine derivative, and method for detecting tumor

摘要

It is intended to provide a radioactive tyrosine derivative represented by the formula (I) or a pharmaceutically acceptable salt thereof:; wherein R¹ represents a group selected from the group consisting of —¹¹CH₃, —¹¹CH₂CH₃, —CH₂¹⁸F, and —CH₂CH₂CH₂¹⁸F.