A series of 5-vinyl-3-pyridinecarbonitriles were synthesized and evaluated as PKC theta inhibitors. The systematic optimization of 4-[(4-methyl-1H-indol-5-yl)amino]-5-[(E)-2-phenylvinyl]-3-pyridinecarbonitrile 3 resulted in the identification of compound 23e as a potent PKC theta inhibitor with good selectivity over PKC delta. (C) 2009 Elsevier Ltd. All rights reserved.