Application of olefin metathesis to the synthesis of ABE ring analogues of methyllycaconitine

The synthesis of four novel ABE ring analogues of methyllycaconitine (MLA) is reported, employing olefin metathesis as the key step for appending the seven-membered B ring onto an AE bicyclic ring system. This strategy allows the stereodivergent synthesis of ABE ring analogues in which the stereochemistry of the AB ring junction is well defined. The compounds are designed as ligands to study binding and function of the α7-nAChR.