| abstract |
This invention relates to compounds of the following formula: Or a pharmaceutically acceptable salt thereof, and a composition containing the same, a preparation method thereof, and a treatment method using the same to promote the water content of the mucosal surface and treat the following diseases: chronic obstructive pulmonary disease (COPD), asthma, bronchiectasis , Acute and chronic bronchitis, cystic fibrosis, emphysema and pneumonia. |