4J70:
reference: Potent Proteasome Inhibitors Derived from the Unnatural Cis-Cyclopropane Isomer of Belactosin A: Synthesis, Biological Activity, and Mode of Action., Shuto S, Kawamura S, Unnno Y, List A, Sasaki T, Tanaka M, Arisawa M, Asai A, Groll M, J Med Chem. 2013 Apr 2. PMID: 23547757

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