The claimed invention relates to methods of modulating mucin synthesis and the therapeutic application of compounds of Formula II in controlling mucin over-production associated with diseases such as chronic obstructive pulmonary diseases (COPD) including asthma and chronic bronchitis, inflammatory lung diseases, cystic fibrosis and acute or chronic respiratory infectious diseases. ##STR00001## wherein X is S, N, O or CR; Y is CRR', O, NR.sub.6, CRR'--CRR' or CR.dbd.CR; Z is NR.sub.6, O, S, CRR' or CRR'--CRR'; R.sub.1-R.sub.3 are independently selected from the group consisting of H, C.sub.1-C.sub.8 alkyl, C.sub.1-C.sub.8 alkoxy, amino, hydroxy, halosubstituted alky and halo; R.sub.4 is ##STR00002## ##STR00003## Q is CR, NR.sub.6 or ##STR00004## R.sub.5 is H or benzyl; R.sub.6 is H, C.sub.1-C.sub.8 alkyl, C.sub.1-C.sub.8 alkoxy, OH or halo; and R and R' are independently H, C.sub.1-C.sub.8 alkyl, C.sub.1-C.sub.8 alkoxy, OH or halo, or a pharmaceutically acceptable salt thereof.