The compounds of a certain formula 1,
in which R1, R7, R8, R9 and n have the meanings as given in the description, are novel effective inhibitors of the type 4 phosphodiesterase.
Fixed combination, non-fixed combination or kit of parts comprising 1-(2-4-[3-(3,4-dimethoxyphenyl)-4,4-dimethyl-5-oxo-4,5-dihydro-1H-pyrazol-1-yl]piperidin-1-yl}-2-oxoethyl)pyrrolidine-2,5-dione, metformin or a pharmaceutically acceptable salt of metformin, and at least one pharmaceutically acceptable auxiliary.