Antiviral tetrahydropyrans

A compound of the formula ##STR92## including a pharmaceutically acceptable salt thereof wherein:

• R.sub.1 is ##STR93## R.sub.2 and R.sub.3 are independently selected from hydrogen, PO.sub.3 H.sub.2, and ##STR94## X.sub.6 is fluoro, chloro, bromo, iodo, hydrogen, methyl, trifluoromethyl, ethyl, n-propyl, 2-fluoroethyl, 2-chloroethyl or ##STR95## X.sub.7 is hydrogen, alkyl, substituted alkyl, or aryl;
• X.sub.9 is chloro, bromo, iodo, hydrogen, methyl, or trifluoromethyl;
• and
• the term "alkyl" refers to straight and branched chain groups of 1 to 10 carbons, the term "substituted alkyl" refers to such alkyl groups having one or more substituents selected from, the group consisting of chloro, bromo, fluoro, iodo, amino, azido, hydroxy, cyano, trialkylammonium (wherein each alkyl group has 1 to 6 carbons), alkoxy of 1 to 6 carbons, aryl and carboxy, and the term "aryl" refers to phenyl and phenyl substituted with one, two or three substituents selected from the group consisting of alkyl of 1 to 6 carbons, alkoxy of 1 to 6 carbons, chloro, bromo, fluoro, iodo, trifluoromethyl, amino, alkylamino of 1 to 6 carbons, dialkylamino wherein each alkyl is of 1 to 6 carbons, nitro, cyano, alkanoyloxy of 2 to 11 carbons, carboxy, carbamoyl, and hydroxy.