Testing of a library of 74 compounds, built around
the basic nakijiquinone C structure, against a battery of
kinases with similar protein domain folds, yielded seven new
inhibitors with low micromolar activity in vitro, including
one VEGFR-2 inhibitor (98; Scheme 18) and four inhibitors
of Tie-2 kinase (99-102; Scheme 18), a protein intimately
involved in angiogenesis and for which, at the beginning of
the study, no inhibitors were known