The enantioselective total synthesis and structure revision of spirodihydrobenzofuranlactam 1 and of its regioisomer 25 are presented. Optically pure (+)-Wieland-Miescher ketone was utilized to construct the AB bicyclic core in 10 steps. Introduction of the resorcylate D-ring unit was achieved by use of our tert-butyl ester metalation sequence. Subsequent stereoselective spirocyclization to form the C-ring was followed by regioselective ring cyanation and lactam formation to produce the pentacyclic structure 1 and its regioisomer 25.

We review in this report the preparation of several side-chain fluorinated analogues of biologically important imidazoles and indoles. The building blocks used should also have applications in other synthetic problems. The addition of "FBr" to vinyl imidazole derivatives was used to prepare b-fluoro- and b,b-difluorohistamine and histidinols, as well as b-fluorourocanic acid. Deoxyfluorination of intermediate acylindoles was used to prepare a series of b,b-difluorotryptamine derivative, including the fluorinated analogue of the important neurotransmitter, serotonin.