The preparation and self-assembly of zinc adeninate macrocycles [Zn-6(adeninate)(6)(pyridine)(6)(dimethylcarbamate)(6)] is described. The macrocycles self-assemble through adenine-adenine hydrogen bonding interactions into a 3-D porous crystalline material that maintains its structural integrity after removal of guest molecules and coordinated pyridine molecules. By adjusting the activation temperature prior to gas adsorption measurements, the size of the pore aperture can be modulated to afford unique gas sorption properties including selective gas adsorption and CO2 sequestration.