D-64406

Several members of the quinazoline class of known tyrosine kinase inhibitors are approved anticancer agents, often showing selectivity for receptors of the HER/ErbB-family. Combining structural elements of this class with the bisindolylmethanone-structure led to a series of novel compounds. These compounds inhibited EGFR in the nanomolar range. Moreover, inhibition of EGFR autophosphorylation in intact A431 cells was shown, with IC(50) values ranging form 0.3-1μM for compound 42, and 0.1-0.3μM for 45. In a panel of 42 human tumor cell lines the sensitivity profile of the novel compounds was shown to be similar to that of the quinazoline class of tyrosine kinase inhibitors lapatinib and erlotinib (Tarceva®).

FLT3 kinase inhibitors are currently under investigation as a new treatment for acute myeloid leukemia. We report here a molecular concept invoking interactions between an aromatic ring and the side chains of Phe691 and Cys828, two residues of the ATP pocket, to obtain potent and specific inhibitors of this kinase. The hypothesis has been validated by the successful design of a new inhibitor prototype showing promising antiproliferative activity in cellular assays.