Azido and Diazarinyl Analogues of Bis-Tyrphostin as Asymmetrical Inhibitors of Dynamin GTPase

Two azidobenzyl amide (4 and 23) and one 3-trifluoromethyl-3H-diazirin-3-ylphenyl (24) analogues of bis-tyrphostin (1, Bis-T) were synthesised as potential photoaffinity labels for the elucidation of the binding site of compound 1 in dynamin I. Of the two azidobenzyl amide analogues (4 and 23), the terminally substituted 23 retained dynamin I GTPase inhibition (IC(50) = 6.4 +/- 2.8 mu M) whilst 4, which was substituted on the central carbon of the amide linker, displayed no activity. Analogue 24 also retained inhibitory activity (IC(50) = 36 +/- 9 mu M). Photoaffinity labelling experiments did not unequivocally elucidate the binding pocket of compound 1. However, compounds 23 and 24 represent the first asymmetrically substituted Bis-T analogues to retain dynamin inhibitory activity, providing a new direction for analogue synthesis.