Pyrrolo[2,3‐d]pyrimidines Containing an Extended 5‐Substituent as Potent and Selective Inhibitors of lck II.

Pyrrolo[2,3-d]pyrimidines containing a 5-(4-phenoxyphenyl) substituent are potent and selective inhibitors of Ick in vitro; some compounds are selective for lck over src. Data are shown for two compounds demonstrating that they are potent and selective inhibitors of IL2 production in cells.