Inhibition de la biosynthese de I'ecdysone par des molecules synthétiques

AbstractWe studied the putative inhibitory activity of about 50 synthetic molecules on the biosynthesis of ecdysone. Most of these molecules had been synthesized according to the conceptual framework of suicide substrate type inhibitors. They potentially react either with well-known catalytic mechanisms (hydroxylations at C-22 and C-25) or with more hypothetic ones (introduction of the keto group at C-6 and the hydroxylation at C-14). The two hydroxylations which take place on the side chain at C-22 and C-25 in the last steps of the ecdysone biosynthetic pathway, and which are catalysed by cytochrome P-450 dependent monooxygenases, can be effectively affected. The essential chemical arrangment which produced a consequent inhibitory effect included an acteylenic or an allenic inhibitory function, near the hydroxylation to inhibit, with a hydroxyl group, preferably grafted in C-20. In order to increase the inhibitory effect, several characteristics gradually appeared : shortness of the side chain, hydroxyl ...