The instant invention provides compounds of formula I which are JAK inhibitors, and as such are useful for the treatment of JAK-mediated diseases such as rheumatoid arthritis, asthma, COPD and cancer.本発明は、JAK阻害剤であり、然るが故にJAK媒介疾患、例えば関節リウマチ、喘息、COPDおよび癌の処置に有用である、式Iの化合物を提供する。