Synthesis of UB-165: A novel nicotinic ligand and anatoxin-a/epibatidine hybrid

UB-165 (5), a hybrid corresponding to natural anatoxin-a and epibatidine, has been synthesised and shows significant potency at the high affinity nicotine binding site in rat brain. Ent-(5) shows a much lower level of activity which parallels the sense of enantiospecificity associated with anatoxin-a.