Design, synthesis, and biological evaluation of a potent, PKC selective, B-ring analog of bryostatin.

[structure: see text] The first member of a new class of five-membered B-ring analogs of bryostatin has been synthesized and tested for its ability to bind and translocate protein kinase C (PKC). This synthesis extends the utility of our previously introduced macrotransacetalization strategy to the formation of five-membered dioxolane B-ring analogs. This analog exhibits potent, single-digit nanomolar affinity to PKC and selectively translocates novel PKC isozymes.