Bortezomib is an inhibitor of 20S proteasome with Ki of 0.6 nM.

MLN9708 is the prodrug of MLN2238 which is an inhibitor of the chymotrypsin-like proteolytic (β5) site of the 20S proteasome with IC50 and Ki of 3.4 nM, 0.93 nM, respectively.

Ixazomib selectively inhibits the chymotrypsin-like proteolytic (β5) site of 20S proteasome with IC50 and Ki of 3.4 nM and 0.93 nM, respectively.

ONX 0912 is an inhibitor of proteasome that targets the chymotrypsin-like activity of the 20S proteasome subunits β5 (IC50 = 36 nM) and LMP7 (IC50 = 82 nM).

Delanzomib is an orally active inhibitor of the chymotrypsin-like activity of proteasome with IC50 of 3.8 nM, with only marginal inhibition of the tryptic and peptidylglutamyl activities of the proteosome.

Celastrol is an inhibitor of HSP90 with antioxidant and anti-inflammatory activities.

PI-1840 is a potent and selective inhibitor for chymotrypsin-like (CT-L) (IC50 value = 27 ± 0.14 nM) over trypsin-like and peptidylglutamyl peptide hydrolyzing (IC50 values > 100 μM) activities of the proteasome.

Epoxomicin is a potent anti-tumor agent isolated from Actinomycetes that is used as a selective and irreversible inhibitor of the 20S proteasome.