| abstract |
Pyridazine derivatives of the formula I DOLLAR F1 in which R · 1 ·, R · 2 ·, R · 3 ·, R · 3 '· and R · 4 · have the meanings given in Claim 1, act as phosphodiesterase IV inhibitors and can be used Treatment of osteoporosis, tumors, cachexia, atherosclerosis, rheumatoid arthritis, multiple sclerosis, diabetes mellitus, inflammatory processes, allergies, asthma, autoimmune diseases, myocardial diseases and AIDS. |