Superstructures are large sized molecules which exist and function at and beyond the nanoscale. By utilizing a diverse array of intermolecular interactions as the information source for assembly processes, large number of complex nanoscale structures and superstructures with a variety of forms and functions has been constructed which exhibit the same principles as exhibited by biological systems i.e. self - organization, self - assembly and self - synthesis processes. In this book, 2,4-(1H,3H) pyrimidinedione (uracil) - based new entities have been designed and synthesized which have capability of recognition of other entities and undergoing self - organization.