Curcumin derivatives inhibit or modulate beta-amyloid precursor protein metabolism

Curcumin-derived oxazoles and pyrazoles were synthesized in order to minimize the metal chelation properties of curcumin. The reduced rotational freedom and the absence of stereoisomers was anticipated to enhance the inhibition of -gamma-secretase. Accordingly, the replacement of the 1,3-dicarbonyl moiety by isosteric heterocycles turned curcumin analogue oxazoles and pyrazoles into potent gamma -secretase inhibitors. Compounds 4a-i were found to be potent inhibitors of -gamma-secretase and displayed activity in the low micromolar range.