Clasto-Lactacystin beta-lactone

Lactacystin is a microbial metabolite isolated from Streptomyces that is now widely used as a selective inhibitor of the 20S proteasome. Clasto-lactacystin beta-lactone was later identified as the active metabolite of lactacystin, resulting from the elimination of cysteine and the formation of a reactive beta-lactone. Both lactacystin and its beta-lactone metabolite induce differentiation and inhibit cell cycle progression in several tumor cell lines. Clasto-lactacystin beta-lactone irreversibly alkylates subunit X of the 20S proteasome. It is at least 10 times more active than the parent compound, this increased activity may be a function of increased cell permeability. Inhibition of proteasome peptidase activity results in the accumulation of a variety of ubiquitinated proteins which would normally undergo rapid degradation. Thus, the effects of clasto-lactacystin beta-lactone are pleiotropic and depend substantially on the expression pattern of signaling proteins within the treated cell.Formal Name: 1R-[1S-1hydroxy-2-methylpropyl]-4R-methyl-6-oxa-2-azabicyclo[3.2.0]heptane-3,7-dione. CAS Number: 154226-60-5. Synonyms: beta-Clastolactacystin, Omuralide. Molecular Formula: C10H15NO4. Formula Weight: 213.2. Purity: >95%. Formulation: (Request formulation change), A solution in methyl acetate. Solubility: DMSO: Soluble. SMILES: O=C1C[C@@H]2OC(=O)[C@@]2(N1)C(O)C(C)C. InChi Code: InChI=1S/C9H13NO4/c1-4(2)7(12)9-5(14-8(9)13)3-6(11)10-9/h4-5,7,12H,3H2,1-2H3,(H,10,11)/t5-,7-,9-/m0/s1. InChi Key: HKJIEDVBDJEURI-GCHGDONOSA-N.