A surprisingly small number of topologies are known in metal-organic frameworks (MOFs) that possess Zn-4(O)(O2C)(6) building units. One of such MOFs having a simple, nonlinear dicarboxylate ligand, 5-methylisophthalate (mip), is targeted and successfully synthesized. The framework, [Zn-4(O)(mip)(3)], is based on a nonuniform, uninodal six-connected net and is featured by complicated meshlike pores with narrow passages. Gas sorption studies reveal the potentials as a prototype from which new MOFs having interesting properties can be derived.