The compounds represented by the following structural formula (I) ##STR1## wherein m and n are independently 1, 2 or 3; R.sub.1 is an C.sub.8 to C.sub.13 alkyl radical and pharmaceutically acceptable salts thereof have been found to be leukotriene antagonists and useful in the treatment of diseases in which leukotrienes are a factor, such as asthma.