Abstract: Pyrano[f]quinoline derivatives of the formula (I): ##STR1## wherein R.sub.1 and R.sub.2 represent hydrogen, hydroxyl group or a group of the formula: ##STR2## wherein n represents an integer from 1 to 4, R.sub.3 and R.sub.4 represent hydrogen or a lower alkyl group, and the broken lines in the rings represent that the bond between the carbon atoms at the 1- and 2-positions and the bond between the carbon atoms at the 9- and 10-positions may be double bonds, and pharmaceutical compositions containing the derivatives. The derivatives and compositions are useful as anti-thrombotic agents, cerebral circulation improving agents, hypotensive agents, anti-angina agents, anti-asthmatic agents, anti-ulcer agents and anti-PAF agents.