Anionocages have been developed as a unique family of hydrogen bonded cages. However, strategies for constructing anionocages are mainly limited to that based on (PO 4 3À )-bisurea coordination, neither the ligands nor the anions lack the simplicity and diversity of the maturely developed analogues based on metal coordination (i.e. metallocage). We report herein a more simple strategy for anionocages design based on (RPO 3 2À )-monourea coordination, utilizing monourea rather than bisurea as the hydrogen binding donor, and RPO 3 2À rather than PO 4 3À