Substituted benzopyrano[3,4-c]pyridines

Abstract

Substituted benzopyrano[3,4-c]pyridines having the following structural formula are disclosed: ##SPC1## In the above formula, R.sub.1 and R.sub.2 are hydrogen, a hydroxyl group or a lower alkoxyl group of from 1 to 6 carbon atoms; and X is an oxygen atom, a sulfur atom, a methylene group or a nitrogen atom substituted by hydrogen, a lower alkyl group of from 1 to 6 carbon atoms or a lower alkanoyl group of from 1 to 6 carbon atoms. The compounds of this invention are prepared by reacting an R.sub.1, R.sub.2 -substituted phenol with a 3-carbethoxy-4-piperidone in the presence of an acid catalyst to give an intermediate R.sub.1, R.sub.2 -substituted benzopyrano[3,4-c]pyridine. N-aminoalkylbenzopyrano[3,4-c]pyridines are obtained by treating the benzopyrano[3,4-c]pyridine with an appropriately substituted alkyl halide. The compounds of this invention are useful as bronchodilators for the treatment of bronchial asthma.

Dependencies are inferred from the claim text.