“…There are numerous examples of 2-amino-substituted pyridine compounds in which the 2-aminopyridines act as ligands (Ranninger et al, 1985;Krizanovic et al, 1993;Luque et al, 1997;Qin et al, 1999;Yip et al, 1999;Lah et al, 2002;Ren et al, 2002;Rivas et al, 2003) or as protonated cations (Luque et al, 1997;Jin et al, 2000Jin et al, , 2001Jin et al, , 2002Jin et al, , 2005Albrecht et al, 2003). All of these studies provide important references to further research into 2-aminopyridines.…”