摘要：

Novel heterocyclic esters of benzopyranopyridines represented by the formula ##STR1## wherein R.sub.1 is hydrogen, lower alkyl, lower alkanoyl, cycloalkyl-lower alkyl, cycloalkyl-lower alkanoyl, lower alkenyl, lower alkynyl, halo-loweralkenyl, phenyl-lower alkyl, phenyl- lower alkenyl or phenyl-lower alkynyl; R.sub.2 is lower alkyl; R.sub.3 is an alkyl having one to twenty carbon atoms or a cycloalkyl-lower alkyl, Y is a straight or branched chain alkylene having one to eight carbon atoms, and R.sub.4 is a group of the formula ##STR2## a is an integer from 1 to 4, b is an integer from 1 to 4 and X is CH.sub.2, O, S or N--R.sub.5 with R.sub.5 being hydrogen or lower alkyl, with the limitation that when X is O, S or N--R.sub.5, a and b each must be 2 and R.sub.6 is hydrogen or a lower alkyl group bonded to a carbon in the ring; and the acid addition salts thereof.

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