Abstract: This invention relates to a compound of the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4, which may be the same or different, each represent a hydrogen or halogen atom or an alkyl or alkoxy group of from 1 to 6 carbon atoms;R.sub.5 and R.sub.6, which may be the same or different, each represent a hydrogen atom, an alkyl group of from 1 to 6 carbon atoms, or an alkenyl group of from 3 to 6 carbon atoms, or R.sub.5 and R.sub.6 together with the nitrogen atom to which they are attached represent a pyrrolidino, piperidino, or morpholino group; andX represents oxygen, sulfur, or a methylene group,or a non-toxic, pharmacologically acceptable acid addition salt thereof, or a racemate, enantiomer, or mixture of enantiomers thereof. The compounds of Formula I are useful in pharmaceutical compositions for treating bronchial asthma and allergic bronchitis.