prevention and or treatment of any obstructive respiratory disease such as asthma chronic bronchitis and chronic obstructive pulmonary disease copd however the compounds of formula i may be administered for the prevention and or treatment of any disease wherein the activity of pde4 receptors is implicated and inhibition of pde4 receptor activity is desired or a disease state which is mediated by pde4 activity for instance a disease state in which pde4 is overexpressed or overactive examples of such diseases include allergic disease states such as atopic dermatitis urticaria allergic rhinitis allergic conjunctivitis vernal conjunctivitis eosinophilic granuloma psoriasis inflammatory arthritis rheumatoid arthritis septic shock ulcerative colitis crohn 39 s disease reperfusion injury of the myocardium and brain chronic glomerulonephritis endotoxic shock cystic fibrosis arterial restenosis atherosclerosis keratosis rheumatoid spondylitis osteoarthritis pyresis diabetes mellitus pneumoconiosis toxic and allergic contact eczema atopic eczema seborrheic eczema lichen simplex sunburn itching in the anogenital area alopecia areata hypertrophic scars discoid lupus erythematosus systemic lupus erythematosus follicular and wide area pyodermias endogenous and exogenous acne acne rosacea beghet 39 s disease anaphylactoid purpura nephritis inflammatory bowel disease leukemia multiple sclerosis gastrointestinal diseases autoimmune diseases and the like they also include neurological and psychiatric disorders such as alzheimer 39 s disease multiple sclerosis amylolaterosclerosis als multiple systems atrophy msa schizophrenia parkinson 39 s disease huntington 39 s disease pick 39 s disease depression stroke and spinal cord injury other features of the invention will become apparent in the course of the following descriptions of exemplary embodiments which are given for illustration of the invention and are not intended to be limiting thereof a solution of 3 cyclopropylmethoxy 4 difluoromethoxy benzaldehyde 5 00 g and 3 5 dichloro 4 methylpyridine 2 57 g in 50 ml dry thf was cooled to u2212 30.