1,3-Diphenylurea is a phenylurea-type cytokinin, a type of plant hormone that induces flower development.
Folke Skoog discovered the effects of cytokinins using coconut milk in the 1940s at the University of Wisconsin–Madison. 1,3-Diphenylurea is a compound that has been thereafter identified in coconut milk.
The cytokinin effect of DPU is considered low as compared to that of adenine derivatives such as zeatin. Nevertheless, there have been subsequent discoveries of other more potent phenylurea-type cytokinins.