Abstract: Disclosed are purine nucleoside compounds that are selective to A3 adenosine receptors and are useful for the treatment of cancer and inflammatory diseases. The compounds are shown by the following general formula (I), including isomers thereof: wherein X is sulfur or oxygen; R1 is hydrogen, alkyl, benzyl, halobenzyl, or phenylalkyl; R2 is hydrogen, halogen, alkoxy, alkenyl, alkynyl, alkylthio, or thio; R3 and R3? are hydrogen, hydroxyalkyl, alkoxycarbonyl, or alkylaminocabonyl, whereas R3 and R3? do not have identical substituents simultaneously; and R4 is hydrogen or alkyl. Also disclosed are a pharmaceutical composition comprising a compound of formula (I), an isomer, or its pharmacologically acceptable salt as an active ingredient and a method for preventing or treating various diseases, state, or condition, including asthma, inflammation, cerebral ischemia, heart diseases, and cancer.

Abstract: The present invention relates to nucleoside derivatives represented by general formulas I and II, their synthetic methods and their pharmacologically acceptable salts thereof, and compositions containing such compounds. Methods for treating hyperproliferative disorders by administering the compounds are also included.