hypoxanthine phosphoribosyltransferase activity inosine 5'-phosphate pyrophosphorylase activity Transphosphoribosidase activity MetaCyc:HYPOXANPRIBOSYLTRAN-RXN GO:0004422 6-hydroxypurine phosphoribosyltransferase activity molecular_function purine-6-thiol phosphoribosyltransferase activity Catalysis of the reaction: IMP + diphosphate = hypoxanthine + 5-phospho-alpha-D-ribose 1-diphosphate. RHEA:17973 6-mercaptopurine phosphoribosyltransferase activity IMP pyrophosphorylase activity IMP:diphosphate phospho-D-ribosyltransferase activity HPRT inosinate pyrophosphorylase activity IMP-GMP pyrophosphorylase activity inosinic acid pyrophosphorylase activity inosinic pyrophosphorylase activity KEGG_REACTION:R01132 guanine-hypoxanthine phosphoribosyltransferase activity hypoxanthine-guanine phosphoribosyltransferase activity IMP diphosphorylase activity HGPRTase activity purine phosphoribosyltransferase activity