Pattern seekers: For the two angiogenicrelevantintegrinsα5β1 and αvβ3, functionalized derivatives of the selective antagonists 1 and 2 could target and discriminate between tumor cells in vivo based on their different integrin patterns and also delay tumor growth in vivo. In addition, the first α5β1‐selectiveintegrin antagonist that enables specific molecular imaging by positron emission tomography