SYNTHESIS AND BINDING OF PHOTOAFFINITY LIGAND CANDIDATES FOR PROTEIN-KINASE-C

Our observation that protein kinase C binding is retained by phorbol e sters modified at the C-3 position has led to the design of a new clas s of photoaffinity ligand candidates. The first members of this class, esters 3 and 4, were synthesized from phorbol and found to bind to PK C with high affinity; the solution photochemistry of 3 leads predomina ntly to insertion products, as required for its use as a PKC receptor probe.