The preparation of amine and guanidine derivatives of phenylalaninamide and tryptophanamide as well as benzylamines from BAL, Rink‐MBHA, and Rink resins has been performed. Cleavage of the target compound gave significant amounts of byproducts compounds in which the linker moiety was attached to the target unit. This side reaction can be avoided when the solid supports are prepared by anchoring the corresponding linker to an aminomethyl resin.

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Tin-lithium exchange and intramolecular carbolithiation (anionic cyclization) have been used to construct the three nitrogen-positional isomers of the azabicyclo[2.2.1]heptane ring system. The 7-azabicyclo[2.2.1]heptane ring system is accessed from either diastereomer of a 2,5-disubstituted pyrrolidine, via a chiral organolithium intermediate. The 2-azabicyclo[2.2.1]heptane ring system is formed stereoselectively in low yield by a tandem cyclization, together with the product from monocyclization. Better yields of the 2-aza ring system can be obtained using an alternative approach from a 2-tributylstannyl-4-allylpyrrolidine, despite the trans arrangement of the tin (and, hence, lithium) atom and the allyl unit. The 1-azabicyclo[2.2.1]heptane ring system is accessed in just three steps from 4-piperidone.

The total synthesis of (+/-)-deethylibophyllidine (1) is described. Three different sequences provide this pentacyclic alkaloid using a common strategy involving a crisscross annulation. Key steps include (i) C/D ring cleavage of a 2-formyloctahydroindolo[2,3-a]quinolizine to obtain octahydroazecino[5,4-b]indoles, via either a chloroformate induced process or a quaternary ammonium salt formation followed by treatment with lithium, and (ii) a tandem process consisting of an intramolecular Pictet-Spengler double cyclization upon a beta-indole position of a 2,3-disubstituted indole to generate the quaternary spiro center of the pentacyclic skeleton of ibophyllidine alkaloids. Attempts to extend the procedure to the construction of the pentacyclic framework of (+/-)-ibophyllidine result in very low yield.

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