New compounds, compositions and methods of inhibition of kinase activity associated with tumorigenesis in a human or animal subject are provided. In certain embodiments, the compounds and compositions are effective to inhibit the activity of at least one serine/threonine kinase or receptor tyrosine kinase. The new compounds and compositions may be used either alone or in combination with at least one additional agent for the treatment of a serine/threonine kinase- or receptor tyrosine kinase-mediated disorder, such as cancer.