Carbonate and oxalate dianions as prolific hydrogen-bond acceptors in supramolecular assembly

In the new inclusion compound [(C2H5)4N+]2·CO3^2–·7(NH2)2CS, the carbonate ion is surrounded by twelve convergent NH donor groups from six thiourea molecules to form a hydrogen-bonded aggregate shaped like two concave three-leaved propellers sharing a common core, whereas in [(n-C3H7)4N+]2·C2O42–·4(NH2)2CS the oxalate ion serves as a hub for binding four thiourea molecules to generate a cross-shaped structural motif