Synthesis and NMR elucidation of novel pentacyclo-undecane diamine ligands

The synthesis and NMR elucidation of eight novel pentacyclo-undecane (PCU) diamine compounds are reported. These ligands are potential anti-inflammatory agents to be used against rheumatoid arthritis (RA). One-dimensional NMR techniques (¹H and ¹³C spectra) show major overlapping of methine resonances of the “cage” (PCU) thereby making it extremely difficult to assign all NMR signals. This overlapping occurs as a result of the substitutions made at the quaternary carbons (C-8/C-11) of the cage. Two-dimensional NMR techniques proved to be a useful tool in overcoming this problem.