KL001 is a small molecule that specifically interacts with cryptochrome (CRY). KL001 prevented ubiquitin-dependent degrdation of CRY, resulting in lengthening of the circadian period. KL001-mediated CRY stabilization inhibited glucagon-induced gluconeogenesis in primary hepatocytes making it a tool to study the regulation of CRY-dependent physiology and aid development of clock-based therapeutics of diabetes.