/az'euh thuy"euh preen'/ , n. Pharm.
a cytotoxic purine analog, C 9 H 7 N 7 O 2 S, used as an immunosuppressive in organ transplantations and in rheumatoid arthritis and connective tissue disorders.
[ 1960-65; coinage appar. based on imidazol, THIO-, and PURINE, parts of the chemical name ]