A series of four Zn2+ metal-organic frameworks containing functionalised isophthalate linkers and 4,4'-bipyridine pillars have been prepared and characterised. Isophthalates which contain -OC3H2n+1 alkoxy side chains (with n = 1, 2 or 3) form frameworks with a 3D pillared-layer topology instead of the typical 2D layer topology of the renowned coordination polymers with an interdigitated structure (CIDs), which is found for shorter -OC2H5 side chains. The gas adsorption properties of the materials were analysed using N2, CO2 and O2 adsorption measurements at low temperatures.