Three isostructural interwoven 3,4-connected mesoporous metal-organic frameworks of pto-a topology (UTSA-28-Cu, UTSA-28-Zn, and UTSA-28-Mn) were synthesized and structurally characterized. Because of their metastable nature, their gas sorption properties are highly dependent on the metal ions and activation profiles. The most stable, UTSA-28a-Cu, exhibits promising gas storage and separation capacities.