This invention relates to novel compounds that are substituted xanthine,derivatives and pharmaceutically acceptablesalts thereof. For example, this invention relates to novel substitutedxanthine derivatives that are derivatives ofpentoxifylline. This invention also provides compositions comprising one ormore compounds of this invention and a carrier and the useof the disclosed compounds and compositions in methods of treating diseasesand conditions for which pentoxifylline and relatedcompounds are beneficial.