The present invention provides compounds which have an inhibitory effect on hormone-sensitive lipase or endothelial lipase. The compounds of the invention are azolopyridin-2-one derivatives of the general formula I wherein the substituents are as defined herein. The compounds of formula I wherein R2 is hydrogen are distinguished by favorable effects on disorders of lipid metabolism. They beneficially influence the HDL to LDL ratio and increase in particular the HDL level and are suitable for the prevention and treatment of dyslipidemias and metabolic syndrome and their diverse sequelae such as atherosclerosis, coronary heart disease, heart failure, obesity and diabetes. The compounds of formula I wherein R1 and R2 together form a ring system are distinguished by favorable effects on metabolic disorders. They beneficially influence lipid and sugar metabolism; in particular they lower the triglyceride level and are suitable for the prevention and treatment of type II diabetes and arteriosclerosis and the diverse sequelae thereof.