Abstract: New compounds of the formula ##STR1## and the pharmaceutically acceptable acid addition salts thereof, wherein M is selected from the group consisting of hydrogen, morpholino, benzylamino, di-n-lower alkylamine, n-lower alkylamine, and aryl piperazino;Z.sub.1 and Z.sub.2 are each independently selected from the group consisting of CH.sub.2, CHOB and C.dbd.O, wherein B is selected from the group consisting of hydrogen and alkanoyl;Y is oxygen or sulfur;n is an integer from 0-4 but cannot be zero when Z.sub.1 is CHOB;m is an integer from 0-4 but cannot be zero when Z.sub.2 is CHOB, or when m is hydrogen;R.sub.1, R.sub.2 and R.sub.3 are each independently hydrogen, halogen, hydroxy, trifluoromethyl, alkyl or alkoxy; andR.sub.4 and R.sub.5 are each independently lower alkyl, with the proviso that both R.sub.4 and R.sub.5 cannot be methyl when M is hydrogen;are antihistamines and are therefore useful in the treatment of respiratory diseases including asthma, hay fever, allergies and the common cold.

Abstract: New compounds of the formula ##STR1## and the pharmaceutically acceptable acid addition salts thereof, wherein Z.sub.1 and Z.sub.2 are each independently selected from the group consisting of CH.sub.2, CHOB and C.dbd.O, wherein B is selected from the group consisting of hydrogen and alkanoyl;Y is oxygen or sulfur;n is an integer from 0-4 but cannot be zero when Z.sub.1 is CHOB;m is an integer from 0-4 but cannot be zero when Z.sub.2 is CHOB; andR.sub.1, R.sub.2 and R.sub.3 are each independently hydrogen, halogen, hydroxy, trifluoromethyl, alkyl or alkoxy;are antihistamines and are therefore useful in the treatment of respiratory diseases including asthma, hay fever, allergies and the common cold.

Abstract: New compounds of the formula ##STR1## and the pharmaceutically acceptable acid addition salts thereof, wherein Z.sub.1 and Z.sub.2 are each independently selected from the group consisting of CH.sub.2, CHOB and C.dbd.O, wherein B is selected from the group consisting of hydrogen and alkanoyl;Y is oxygen or sulfur;n is an integer from 0-4 but cannot be zero when Z.sub.1 is CHOB;m is an integer from 0-4 but cannot be zero when Z.sub.2 is CHOB; andR.sub.1, R.sub.2 and R.sub.3 are each independently hydrogen, halogen, hydroxy, trifluoromethyl, alkyl or alkoxy;are antihistamines and are therefore useful in the treatment of respiratory diseases including asthma, hay fever, allergies and the common cold.