IBMX, also known as 1-Methyl-3-Isobutylxanthine and Isobutylmethylxanthine, is a widely-used inhibitor of cAMP and cGMP PDEs. It has been shown that the increase in cellular cAMP and cGMP levels, resulting from the inhibition of PDEs by IBMX, activates cyclicnucleotide-regulated protein kinases. IBMX does not inhibit PDE8A, PDE8B, or PDE9.

≥98% by HPLC

IBMX inhibits PDEs as listed below.
PDE     IC50:
PDE1     19 µM
PDE2     50 µM
PDE3     18 µM
PDE4     13 µM
PDE5     32 µM
PDE7     7 µM
PDE11     50 µM

Solubility in ethanol is ~5 mg/ml and DMSO is ~10 mg/ml. For biological experiments, dilute the organic solvent into aqueous buffers or isotonic saline.

A crystalline solid.

Store at or below –20°C. Solid form is stable at least 12 months from date of receipt, when stored as directed. Do not store aqueous solutions for more than one day.

1. Fawcett, L., et al., Proc. Natl. Acad. Sci. USA 2000; 97(7): 3702-3707.
2. Snyder, S.H., et al., Proc. Natl. Acad. Sci. USA 1981; 78(5): 3260-3264.

PDE

Inhibitor