This invention relates to novel compounds that are substituted xanthine derivatives and pharmaceutically acceptable salts thereof. In particular, this invention relates to novel substituted xanthine derivatives that are derivatives of a pentoxifylline metabolite. This invention also provides compositions comprising one or more compounds of this invention and a carrier and the use of the disclosed compounds and compositions in methods of treating diseases and conditions for which pentoxifylline and related compounds are beneficial. The compounds of the invention are represented by one of the following structural formulas:wherein the values of R1, R2, Y1 and Y2 are described herein.
