The 1, lO-phenanthrolines and substituted analogues are quite important mainly due to their metal chelating properties. Taylor-made 1, lO-phenanthrolines (usually as their metal complexes) have been investigated in the areas of molecular recognition, catalysis, cleavages of DNA, sensing agents and as ionophores. The synthesis of a number of substituted 1, lO-phenanthrolines such as 2-iod0,~ 2-alkoxy3, 2-hydrazino: 2-amin0,~ 2- ...