Acetylacetonato-lanthanide complexes as eminent catalytic sites for artificial ribonucleases.

Acetylacetonato complexes of lutetium, ytterbium, thulium, and europium ions efficiently hydrolyze the phosphodiester linkage in adenylyl(3'-5')adenosine. The pseudo first-order rate constant (3.2 x 10(-2) h-1) at pH 7.2 and 30 degrees C for the 1:1 lutetium-acetylacetonato complex (0.5 mmol dm-3) is close to the value (3.5 x 10(-2) h-1) for free lutetium ion of the same concentration. Potentialities of these complexes as the catalytic sites of artificial ribonucleases are indicated.