Four Co II /Mn II coordination compounds, namely, [Co(dpq)(L1)(H 2 O) 1.5 ] (1), [Co(dpq)(L2)(H 2 O) 2 ]·H 2 O (2), [Mn 2 (dpq) 2 (L2) 2 ]·2H 2 O (3), and [Mn(dpq)(L3)] (4) [H 2 L1 = 5-methylisophthalic acid, H 2 L2 = 5-hydroxyisophthalic acid, and H 2 L3 = bis(sulfanediyl) thiadiazole diacetic acid] were obtained from hydrothermal reactions of dipyrido [3,2-d:2Ј,3Ј-f]quinoxaline (dpq) and three structurally related mixed dicarboxylate ligands. Single crystal X-ray diffraction analysis reveals that compound 1 consists of a dinuclear Co II cluster linked by two carboxylate groups from different L1 anions and a coordination water molecule. Compound 2 is a dimeric structure based on a pair of L2 anions and two Co II ions. Both compounds are finally extended into three dimensional (3D) supramolecular networks