9-(Hydroxy, lower alkoxy or lower alkanoyloxy)-2-(1H-tetrazol-5-yl)naphtho-(2,1-b)-pyran-1-ones and anti-allergic use thereof

摘要

This invention relates to Compounds of formula II: <IMAGE> 11 wherein Y is formyl, carboxylic acid, acrylic acid, cyano or tetrazolo; X is hydrogen, lower alkanoyl or lower alkyl, and their non-toxic, pharmaceutically acceptable salts are disclosed. These compounds are useful in the prevention of allergic and asthmatic reactions.