4720-73-4Relevant academic research and scientific papers
Switching Selectivity in Copper-Catalyzed Transfer Hydrogenation of Nitriles to Primary Amine-Boranes and Secondary Amines under Mild Conditions
Song, Hao,Xiao, Yao,Zhang, Zhuohua,Xiong, Wanjin,Wang, Ren,Guo, Liangcheng,Zhou, Taigang
, p. 790 - 800 (2022/01/11)
A simple and efficient copper-catalyzed selective transfer hydrogenation of nitriles to primary amine-boranes and secondary amines with an oxazaborolidine-BH3 complex is reported. The selectivity control was achieved under mild conditions by switching the solvent and the copper catalysts. More than 30 primary amine-boranes and 40 secondary amines were synthesized via this strategy in high selectivity and yields of up to 95%. The strategy was applied to the synthesis of 15N labeled in 89% yield.
Synthesis and anti-parasitic activity of N-benzylated phosphoramidate Mg2+-chelating ligands
Adeyemi, Christiana M.,Hoppe, Heinrich C.,Isaacs, Michelle,Mnkandhla, Dumisani,Lobb, Kevin A.,Klein, Rosalyn,Kaye, Perry T.
, (2020/11/05)
A series of N-benzylated phosphoramidate esters, containing a 3,4-dihydroxyphenyl Mg2+-chelating group, has been synthesised in five steps as analogues of fosmidomycin, a Plasmodium falciparum 1-deoxy-1-D-xylulose-5-phosphate reductoisomerase (PfDXR) inhibitor. The 3,4-dihydroxyphenyl group effectively replaces the Mg2+-chelating hydroxamic acid group in fosmidomycin. The compounds showed very encouraging anti-parasitic activity with IC50 values of 5.6–16.4 μM against Plasmodium falciparum parasites and IC50 values of 5.2 – 10.2 μM against Trypanosoma brucei brucei (T.b.brucei). Data obtained from in silico docking of the ligands in the PfDXR receptor cavity (3AU9)5 support their potential as PfDXR inhibitors.
Preparation of the Ru3(CO)8-pyridine-alcohol cluster and its use for the selective catalytic transformation of primary to secondary amines
Singh, Ajeet,Mobin, Shaikh M.,Mathur, Pradeep
, p. 14033 - 14040 (2018/11/23)
The synthesis of pyridine alcohol based ruthenium carbonyl clusters Ru3(hep)2(CO)8 (1), Ru3(hpp)2(CO)8 (2), and Ru3(bhmp-H)2(CO)8 (3) {hep-H = 2-(2-hydroxyethyl)pyridine, hpp-H = 2-(3-hydroxypropyl)pyridine and bhmp-H2 = 2,6-bis(hydroxymethyl)pyridine} has been carried out by the reaction of the corresponding pyridine-alcohol ligands with Ru3(CO)12. Clusters 1-3 have been characterized using elemental analysis, NMR, FT-IR, mass spectrometry and single-crystal X-ray structures. The clusters were explored for the selective catalytic transformation of primary amines into secondary amines using alcohols as the mono-alkylating agents via hydrogen transfer reactions. All three display efficient catalytic activity with 1 being the most effective.
Prospective Evaluation of Free Energy Calculations for the Prioritization of Cathepsin L Inhibitors
Kuhn, Bernd,Tichy, Michal,Wang, Lingle,Robinson, Shaughnessy,Martin, Rainer E.,Kuglstatter, Andreas,Benz, J?rg,Giroud, Maude,Schirmeister, Tanja,Abel, Robert,Diederich, Fran?ois,Hert, Jér?me
, p. 2485 - 2497 (2017/04/03)
Improving the binding affinity of a chemical series by systematically probing one of its exit vectors is a medicinal chemistry activity that can benefit from molecular modeling input. Herein, we compare the effectiveness of four approaches in prioritizing building blocks with better potency: selection by a medicinal chemist, manual modeling, docking followed by manual filtering, and free energy calculations (FEP). Our study focused on identifying novel substituents for the apolar S2 pocket of cathepsin L and was conducted entirely in a prospective manner with synthesis and activity determination of 36 novel compounds. We found that FEP selected compounds with improved affinity for 8 out of 10 picks compared to 1 out of 10 for the other approaches. From this result and other additional analyses, we conclude that FEP can be a useful approach to guide this type of medicinal chemistry optimization once it has been validated for the system under consideration.
A General and Selective Rhodium-Catalyzed Reduction of Amides, N-Acyl Amino Esters, and Dipeptides Using Phenylsilane
Das, Shoubhik,Li, Yuehui,Lu, Liang-Qiu,Junge, Kathrin,Beller, Matthias
supporting information, p. 7050 - 7053 (2016/05/19)
This article describes a selective reduction of functionalized amides, including N-acyl amino esters and dipeptides, to the corresponding amines using simple [Rh(acac)(cod)]. The catalyst shows excellent chemoselectivity in the presence of different sensitive functional moieties. A selective reduction of functionalized amides, including N-acyl amino esters and dipeptides, to the corresponding amines using simple [Rh(acac)(cod)] is described (see scheme). The catalyst shows excellent chemoselectivity in the presence of different sensitive functional moieties. Even the selective reduction of a secondary amide bond in the presence of a ketone is possible.
Influence of functionalities over polymer, trimer, dimer formation and optical properties of cadmium dithiocarbamates
Manar, Krishna K.,Yadav, Manoj K.,Anamika,Drew, Michael G.B.,Singh, Nanhai
, p. 592 - 599 (2016/07/21)
Homoleptic cadmium(II) bis(dithiocarbamate) complexes having polymeric [Cd(L)2]∞(L?=?C7H5O2CH2NCS2CH2C6H5(L1), 1; C6H4NO2CH2NCS2CH2C4H3O (L2), 2; C6H4FCH2NCS2CH2C4H3O (L3), 3), trinuclear [Cd(L4)2]3(L4?=?4-ClC6H4CH2NCS2CH2C4H3O, 4) and dinuclear [Cd(L5)2]2, (L5?=?3-ClC6H4CH2NCS2CH2C6H5, 5) structures have been synthesized and characterized by elemental analyses, spectroscopy (IR,1H and13C {1H} NMR and UV–Vis.) and their structures have been revealed by X-ray crystallography. In 1–3 the dithiocarbamate ligands are uniquely bonded to the Cd atoms in a μ2,κ2S,S-chelating-bridging fashion, portraying 1D coordination polymeric structures in which the cadmium(II) ions adopt six coordinate distorted octahedral structures. In 4 the six dithiocarbamate ligands are spectacularly arranged about the Cd atoms resulting in a centrosymmetric trinuclear complex in which the central metal adopts an octahedral geometry and the terminal Cd atoms are in square pyramidal environments. Complex 5 has the well-established centrosymmetric dimeric structure in which the metal atoms have a five-coordinate trigonal bipyramidal geometry. Complexes 1–4 are rare examples of polymeric and trinuclear cadmium dithiocarbamate complexes. 1–5 show luminescent characteristics in solution and in the solid state arising from the metal perturbed intra-ligand charge transfer (ILCT) states. Their TG analyses show a single step decomposition with the formation of CdS nanoparticles, which have been examined by PXRD and HRTEM.
Iridium-catalyzed reduction of secondary amides to secondary amines and imines by diethylsilane
Cheng, Chen,Brookhart, Maurice
, p. 11304 - 11307 (2012/09/05)
Catalytic reduction of secondary amides to imines and secondary amines has been achieved using readily available iridium catalysts such as [Ir(COE) 2Cl]2 with diethylsilane as reductant. The stepwise reduction to secondary amine proceeds through an imine intermediate that can be isolated when only 2 equiv of silane is used. This system requires low catalyst loading and shows high efficiency (up to 1000 turnovers at room temperature with 99% conversion have been attained) and an appreciable level of functional group tolerance.
Zinc-catalyzed chemoselective reduction of tertiary and secondary amides to amines
Das, Shoubhik,Addis, Daniele,Junge, Kathrin,Beller, Matthias
experimental part, p. 12186 - 12192 (2011/11/07)
General and convenient procedures for the catalytic hydrosilylation of secondary and tertiary amides under mild conditions have been developed. In the presence of inexpensive zinc catalysts, tertiary amides are easily reduced by applying monosilanes. Key to success for the reduction of the secondary amides is the use of zinc triflate and disilanes with dual Si-H moieties. The presented hydrosilylations proceed with excellent chemoselectivity in the presence of sensitive ester, nitro, azo, nitrile, olefins, and other functional groups, thus making the method attractive for organic synthesis.
Ruthenium-catalyzed nitro and nitrile compounds coupling with alcohols: Alternative route for N-substituted amine synthesis
Cui, Xinjiang,Zhang, Yan,Shi, Feng,Deng, Youquan
supporting information; experimental part, p. 2587 - 2591 (2011/04/12)
The one-pot synthesis of N-substituted secondary amines from nitrobenzenes and benzonitriles has been developed (see scheme). This report presents a versatile and simple method for the synthesis of N-substituted amines in excellent yield and high efficiency from nitro and nitrile compounds with alcohols.
Preparation of benzolactams by Pd(OAC)2-catalyzed direct aromatic carbonylation
Orito, Kazuhiko,Horibata, Akiyoshi,Nakamura, Takatoshi,Ushito, Harumi,Nagasaki, Hideo,Yuguchi, Motoki,Yamashita, Satoshi,Tokuda, Masao
, p. 14342 - 14343 (2007/10/03)
We developed a new method for Pd(II)-catalyzed direct aromatic carbonylation in a phosphine-free catalytic system using Pd(OAc)2 and Cu(OAc)2 in an atmosphere of CO gas containing air. The carbonylation proceeded with ortho-palladation, inducing a remarkable site selectivity to afford a variety of five- or six-membered benzolactams from secondary ω-arylalkylamines, such as N-alkylbenzylamines or N-alkylphenethylamines. Copyright
