247068-81-1Relevant articles and documents
Enzyme inhibition by hydroamination: Design and mechanism of a hybrid carmaphycin-syringolin enone proteasome inhibitor
Trivella, Daniela B.B.,Pereira, Alban R.,Stein, Martin L.,Kasai, Yusuke,Byrum, Tara,Valeriote, Frederick A.,Tantillo, Dean J.,Groll, Michael,Gerwick, William H.,Moore, Bradley S.
, p. 782 - 791 (2014)
Hydroamination reactions involving the addition of an amine to an inactivated alkene are entropically prohibited and require strong chemical catalysts. While this synthetic process is efficient at generating substituted amines, there is no equivalent in small molecule-mediated enzyme inhibition. We report an unusual mechanism of proteasome inhibition that involves a hydroamination reaction of alkene derivatives of the epoxyketone natural product carmaphycin. We show that the carmaphycin enone first forms a hemiketal intermediate with the catalytic Thr1 residue of the proteasome before cyclization by an unanticipated intramolecular alkene hydroamination reaction, resulting in a stable six-membered morpholine ring. The carmaphycin enone electrophile, which does not undergo a 1,4-Michael addition as previously observed with vinyl sulfone and α,β-unsaturated amide-based inhibitors, is partially reversible and gives insight into the design of proteasome inhibitors for cancer chemotherapy.
Macrocyclic Immunoproteasome Inhibitors as a Potential Therapy for Alzheimer's Disease
Lee, Min Jae,Bhattarai, Deepak,Jang, Hyeryung,Baek, Ahreum,Yeo, In Jun,Lee, Seongsoo,Miller, Zachary,Lee, Sukyeong,Hong, Jin Tae,Kim, Dong-Eun,Lee, Wooin,Kim, Kyung Bo
, p. 10934 - 10950 (2021/08/20)
Previously, we reported that immunoproteasome (iP)-targeting linear peptide epoxyketones improve cognitive function in mouse models of Alzheimer's disease (AD) in a manner independent of amyloid β. However, these compounds' clinical prospect for AD is limited due to potential issues, such as poor brain penetration and metabolic instability. Here, we report the development of iP-selective macrocyclic peptide epoxyketones prepared by a ring-closing metathesis reaction between two terminal alkenes attached at the P2 and P3/P4 positions of linear counterparts. We show that a lead macrocyclic compound DB-60 (20) effectively inhibits the catalytic activity of iP in ABCB1-overexpressing cells (IC50: 105 nM) and has metabolic stability superior to its linear counterpart. DB-60 (20) also lowered the serum levels of IL-1α and ameliorated cognitive deficits in Tg2576 mice. The results collectively suggest that macrocyclic peptide epoxyketones have improved CNS drug properties than their linear counterparts and offer promising potential as an AD drug candidate.
Continuous Process Improvement in the Manufacture of Carfilzomib, Part 1: Process Understanding and Improvements in the Commercial Route to Prepare the Epoxyketone Warhead
Dornan, Peter K.,Anthoine, Travis,Beaver, Matthew G.,Cheng, Guilong Charles,Cohen, Dawn E.,Cui, Sheng,Lake, William E.,Langille, Neil F.,Lucas, Susan P.,Patel, Jenil,Powazinik, William,Roberts, Scott W.,Scardino, Chris,Tucker, John L.,Spada, Simone,Zeng, Alicia,Walker, Shawn D.
, p. 481 - 489 (2020/04/10)
Epoxyketone 4 is an isolated intermediate in the manufacturing route to the commercial proteasome inhibitor carfilzomib (Kyprolis). Commercial process development and optimization efforts toward the preparation of epoxyketone 4 highlighted several opportunities for process improvement. In this article, three case studies are presented that demonstrate how a detailed understanding of the reaction mechanism led to improvements that increased the overall robustness of the process. In the first case study, the mechanism of racemization of an α-chiral enone was investigated, resulting in the development of an improved aqueous workup procedure. Next, the stability of a bleach/pyridine mixture used for the step 3 epoxidation reaction was studied, leading to the identification of pyridine as a key raw material and improved reaction conditions and control strategy to meet the conversion target. Finally, oxidized butylated hydroxytoluene (oBHT) was identified as an impurity arising from the use of BHT-stabilized tetrahydrofuran in steps preceding the oxidation. The process understanding obtained from these investigations led to the implementation of process improvements that improved the robustness of the process. The development of a second-generation route to 4 is the subject of part 2 in this series (DOI: 10.1021/acs.oprd.0c00052).
