38136-29-7Relevant academic research and scientific papers
A Diverse Library of Chiral Cyclopropane Scaffolds via Chemoenzymatic Assembly and Diversification of Cyclopropyl Ketones
Nam, Donggeon,Steck, Viktoria,Potenzino, Robert J.,Fasan, Rudi
, p. 2221 - 2231 (2021/02/16)
Chiral cyclopropane rings are key pharmacophores in pharmaceuticals and bioactive natural products, making libraries of these building blocks a valuable resource for drug discovery and development campaigns. Here, we report the development of a chemoenzymatic strategy for the stereoselective assembly and structural diversification of cyclopropyl ketones, a highly versatile yet underexploited class of functionalized cyclopropanes. An engineered variant of sperm whale myoglobin is shown to enable the highly diastereo- and enantioselective construction of these molecules via olefin cyclopropanation in the presence of a diazoketone carbene donor reagent. This biocatalyst offers a remarkably broad substrate scope, catalyzing this reaction with high stereoselectivity across a variety of vinylarene substrates as well as a range of different α-aryl and α-alkyl diazoketone derivatives. Chemical transformation of these enzymatic products enables further diversification of these molecules to yield a collection of structurally diverse cyclopropane-containing scaffolds in enantiopure form, including core motifs found in drugs and natural products as well as novel structures. This work illustrates the power of combining abiological biocatalysis with chemoenzymatic synthesis for generating collections of optically active scaffolds of high value for medicinal chemistry and drug discovery.
Remote Regioselective Radical C-H Functionalization of Unactivated C-H Bonds in Amides: The Synthesis of gem-Difluoroalkenes
Hu, Qu-Ping,Cheng, Jing,Wang, Ying,Shi, Jie,Wang, Bi-Qin,Hu, Ping,Zhao, Ke-Qing,Pan, Fei
supporting information, p. 4457 - 4462 (2021/05/26)
The site-selective functionalization of unactivated aliphatic amines is an attractive and challenging synthetic approach. We herein report a general strategy for the remote site-selective functionalization of unactivated C(sp3)-H bonds in amides by photogenerated amidyl radicals to form gem-difluoroalkenes with trifluoromethyl-substituted alkenes. The site selectivity is controlled by a 1,5-hydrogen atom transfer (HAT) process of the amide. This photocatalyzed transformation shows both chemo- and site-selectivity, facilitating the formation of a secondary, tertiary, or quaternary carbon center.
Direct and Enantioselective Aldol Reactions Catalyzed by Chiral Nickel(II) Complexes
Kennington, Stuart C. D.,Teloxa, Saul F.,Mellado-Hidalgo, Miguel,Galeote, Oriol,Puddu, Sabrina,Bellido, Marina,Romea, Pedro,Urpí, Fèlix,Aullón, Gabriel,Font-Bardia, Mercè
supporting information, p. 15307 - 15312 (2021/06/11)
A direct and asymmetric aldol reaction of N-acyl thiazinanethiones with aromatic aldehydes catalyzed by chiral nickel(II) complexes is reported. The reaction gives the corresponding O-TIPS-protected anti-aldol adducts in high yields and with remarkable stereocontrol and atom economy. Furthermore, the straightforward removal of the achiral scaffold provides enantiomerically pure intermediates of synthetic interest, which involve precursors for anti-α-amino-β-hydroxy and α,β-dihydroxy carboxylic derivatives. Theoretical calculations explain the observed high stereocontrol.
Decarboxylative Borylation of mCPBA-Activated Aliphatic Acids
Wei, Dian,Liu, Tu-Ming,Zhou, Bo,Han, Bing
supporting information, p. 234 - 238 (2020/01/02)
A decarboxylative borylation of aliphatic acids for the synthesis of a variety of alkylboronates has been developed by mixing m-chloroperoxybenzoic acid (mCPBA)-activated fatty acids with bis(catecholato)diboron in N,N-dimethylformamide (DMF) at room temperature. A radical chain process is involved in the reaction which initiates from the B-B bond homolysis followed by the radical transfer from the boron atom to the carbon atom with subsequent decarboxylation and borylation.
Modular Tuning of Electrophilic Reactivity of Iridium Nitrenoids for the Intermolecular Selective α-Amidation of β-Keto Esters
Lee, Minhan,Jung, Hoimin,Kim, Dongwook,Park, Jung-Woo,Chang, Sukbok
supporting information, p. 11999 - 12004 (2020/08/06)
We report herein an Ir-catalyzed intermolecular amino group transfer to β-keto esters (amides) to access α-aminocarbonyl products with excellent chemoselectivity. The key strategy was to engineer electrophilicity of the putative Ir-nitrenoids by tuning electronic property of the κ2-N,O chelating ligands, thus facilitating nucleophilic addition of enol π-bonds of 1,3-dicarbonyl substrates.
Photocatalytic Intramolecular C-H Amination Using N-Oxyureas as Nitrene Precursors
Ivanovich, Ryan A.,Polat, Dilan E.,Beauchemin, André M.
supporting information, p. 6360 - 6364 (2020/09/02)
Nitrenes are remarkable high-energy chemical species that enable direct C-N bond formation, typically via controlled reactions of metal-stabilized nitrenes. Here, in contrast, the combined use of photocatalysis with careful engineering of the precursor enabled C-H amination forming imidazolidinones and related nitrogen heterocycles from readily accessible hydroxylamine precursors. Preliminary mechanistic results are consistent with the formation of free carbamoyl triplet nitrenes as reactive intermediates.
Hydroxamate-Based Selective Macrophage Elastase (MMP-12) Inhibitors and Radiotracers for Molecular Imaging
Gona, Kiran,Toczek, Jakub,Ye, Yunpeng,Sanzida, Nowshin,Golbazi, Arvene,Boodagh, Parnaz,Salarian, Mani,Jung, Jae-Joon,Rajendran, Saranya,Kukreja, Gunjan,Wu, Terence L.,Devel, Laurent,Sadeghi, Mehran M.
, p. 15037 - 15049 (2020/11/30)
Macrophage elastase [matrix metalloproteinase (MMP)-12] is the most upregulated MMP in abdominal aortic aneurysm (AAA) and, hence, MMP-12-targeted imaging may predict AAA progression and rupture risk. Here, we report the design, synthesis, and evaluation of three novel hydroxamate-based selective MMP-12 inhibitors (CGA, CGA-1, and AGA) and the methodology to obtain MMP-12 selectivity from hydroxamate-based panMMP inhibitors. Also, we report two 99mTc-radiotracers, 99mTc-AGA-1 and 99mTc-AGA-2, derived from AGA. 99mTc-AGA-2 displayed faster blood clearance in mice and better radiochemical stability compared to 99mTc-AGA-1. Based on this, 99mTc-AGA-2 was chosen as the lead tracer and tested in murine AAA. 99mTc-AGA-2 uptake detected by autoradiography was significantly higher in AAA compared to normal aortic regions. Specific binding of the tracer to MMP-12 was demonstrated through ex vivo competition. Accordingly, this study introduces a novel family of selective MMP-12 inhibitors and tracers, paving the way for further development of these agents as therapeutic and imaging agents.
Discovery of TD-0212, an Orally Active Dual Pharmacology AT1 Antagonist and Neprilysin Inhibitor (ARNI)
McKinnell, R. Murray,Fatheree, Paul,Choi, Seok-Ki,Gendron, Roland,Jendza, Keith,Olson Blair, Brooke,Budman, Joe,Hill, Craig M.,Hegde, Laxminarayan G.,Yu, Cecile,McConn, Donavon,Hegde, Sharath S.,Marquess, Daniel G.,Klein, Uwe
supporting information, p. 86 - 91 (2019/01/04)
Dual inhibition of angiotensin-converting enzyme (ACE) and neprilysin (NEP) by drugs such as omapatrilat produces superior antihypertensive efficacy relative to ACE inhibitors but is associated with a higher risk of life-threatening angioedema due to bradykinin elevations. We hypothesized that dual AT1 (angiotensin II type 1 receptor) blockade and NEP inhibition with a single molecule would produce similar antihypertensive efficacy to omapatrilat without the risk of angioedema since ACE (the rate limiting enzyme in bradykinin metabolism) would remain uninhibited. Merging the structures of losartan (an AT1 antagonist) and thiorphan (a NEP inhibitor) led to the discovery of a novel series of orally active, dual AT1 antagonist/NEP inhibitors (ARNIs) exemplified by compound 35 (TD-0212). In models of renin-dependent and -independent hypertension, 35 produced blood pressure reductions similar to omapatrilat and combinations of AT1 receptor antagonists and NEP inhibitors. Upper airway angioedema risk was assessed in a rat tracheal plasma extravasation (TPE) model. Unlike omapatrilat, 35 did not increase TPE at antihypertensive doses. Compound 35 therefore provides the enhanced activity of dual AT1/NEP inhibition with a potentially lower risk of angioedema relative to dual ACE/NEP inhibition.
Synthetic Utility of N-Benzoyloxyamides as an Alternative Precursor of Acylnitrenoids for γ-Lactam Formation
Huh, Soohee,Hong, Seung Youn,Chang, Sukbok
supporting information, p. 2808 - 2812 (2019/04/17)
Described herein is the development of a new entry of acylnitrenoid precursors for γ-lactam synthesis via an intramolecular C-H amidation reaction. Upon Ir catalysis, N-benzoyloxyamides serve as efficient substrates to afford 5-membered amides. Mechanistic studies revealed that the generation of a putative Ir-carbonylnitrenoid via N-O bond cleavage is facilitated by the chelation of countercations. This protocol offers a convenient and step-economic route to γ-lactams starting from the corresponding carboxylic acids.
Rational design of a new class of toll-like receptor 4 (tlr4) tryptamine related agonists by means of the structure- and ligand-based virtual screening for vaccine adjuvant discovery
Honegr, Jan,Dolezal, Rafael,Malinak, David,Benkova, Marketa,Soukup, Ondrej,De Almeida, Joyce S. F. D.,Franca, Tanos C. C.,Kuca, Kamil,Prymula, Roman
, (2018/01/26)
In order to identify novel lead structures for human toll-like receptor 4 (hTLR4) modulation virtual high throughput screening by a peta-flops-scale supercomputer has been performed. Based on the in silico studies, a series of 12 compounds related to tryptamine was rationally designed to retain suitable molecular geometry for interaction with the hTLR4 binding site as well as to satisfy general principles of drug-likeness. The proposed compounds were synthesized, and tested by in vitro and ex vivo experiments, which revealed that several of them are capable to stimulate hTLR4 in vitro up to 25% activity of Monophosphoryl lipid A. The specific affinity of the in vitro most potent substance was confirmed by surface plasmon resonance direct-binding experiments. Moreover, two compounds from the series show also significant ability to elicit production of interleukin 6.
