Quick Biochemistry - Nucleic Acids (Section 2 - No. 20)
The action of 6-Mercapto purine results in the inhibition of the following conversion:
IMP→XMP
Ribose 5 phosphate → PRPP
PRPP→5-phospho→B-D-ribosylamine
Glycinamide ribosyl 5-phosphate → formylglycinamide ribosyl-5-phosphate