3005-60-5Relevant academic research and scientific papers
Expedient access to pre-organized α-helix mimetics based on an isocinchomeronic acid core
Drennen, Brandon,MacKerell, Alexander D.,Fletcher, Steven
, p. 6819 - 6822 (2015)
A previously reported terephthalamide-based α-helix mimetic was modified by introducing a pyridine nitrogen and converting a tertiary amide to a secondary amide, which afforded a second intramolecular hydrogen bond to further influence the projection of t
Cathepsin K inhibitors based on 2-amino-1,3,4-oxadiazole derivatives
Gontijo, Talita B.,Lima, Patrícia S.,Icimoto, Marcelo Y.,Neves, Raquel Le?o,de Alvarenga, érika C.,Carmona, Adriana K.,de Castro, Alexandre A.,Ramalho, Teodorico C.,da Silva Júnior, Eufranio N.,de Freitas, Rossimiriam P.
, (2021/02/26)
Two new series of hitherto unknown dipeptides, containing an electrophilic nitrile or a non-electrophilic 2-amino-1,3,4-oxadiazole moiety were synthesized and evaluated in vitro as Cathepsin K (Cat K) inhibitors. From 14 compounds obtained, the oxadiazole derivatives 10a, 10b, 10e, and 10g acted as enzymatic competitive inhibitors with Ki values between 2.13 and 7.33 μM. Molecular docking calculations were carried out and demonstrated that all inhibitors performed hydrogen bonds with residues from the enzyme active site, such as Asn18. The best inhibitors (10a, 10b, 10g) could also perform these bonds with Cys25, and 10a showed the most stabilizing interaction energy (?134.36 kcal mol?1) with the active cavity. For the first time, derivatives based in 2-amino-1,3,4-oxadiazole scaffolds were evaluated, and the results suggested that this core displays a remarkable potential as a building block for Cat K inhibitors.
Amidation of Aldehydes with Amines under Mild Conditions Using Metal-Organic Framework Derived NiO@Ni Mott-Schottky Catalyst
Goel, Bharat,Vyas, Ved,Tripathi, Nancy,Kumar Singh, Ajit,Menezes, Prashanth W.,Indra, Arindam,Jain, Shreyans K.
, p. 5743 - 5749 (2020/09/09)
Here we report a facile method for the synthesis of nickel oxide-nickel (NiO@Ni) Mott-Schottky catalyst employing metal-organic framework (MOF) as the precursor. A direct amidation protocol of aldehydes with amines has been optimized under mild conditions using NiO@Ni Mott-Schottky catalyst and it shows far better catalytic activity than the NiO?Ni nanoparticles prepared from simple Ni2+ salt under similar reaction conditions. The heterogeneous catalyst is robust, recyclable and efficient to provide comparable yield to costly ligand-based homogeneous Ni catalysts. The scope of the reaction protocol has been explored with variably substituted substrates. The reaction initiates by homolytic cleavage of peroxide and proceeds through radical mechanism.
Selective conversion of primary amides to esters promoted by KHSO4
Sattenapally, Narsimha,Sharma, Jhanvi,Hou, Yuqing
, p. 174 - 183 (2018/09/10)
Primary amides, either aliphatic or aromatic, are easily converted to the corresponding esters via reflux in lower primary alcohols in the presence of KHSO4. Secondary amides lead to complicated mixtures under analogous conditions, whereastertiary amides were inert. Use of isopropyl alcohol resulted inthe formation of product atslower rate and lower yieldalong withside products, whereas, use of tertiary alcoholsdid not give successful conversion andallyl and benzyl alcohol provided complex mixtures.
Synthesis of Hydrazones from Amino Acids and their Antimicrobial and Cytotoxic Activities
Abid, Obaid-Ur-Rahman,Khatoon, Ghamama,Arfan, Muhammad,Sajid, Imran,Langer, Peter,Rehman, Wajid,Rahim, Fazal,Yasir, Muhammad,Waqar, Muhammad,Haleem, Kashif Syed
, p. 1079 - 1087 (2017/09/26)
Hydrazones 6a–6n were synthesized from different amino acids with various aldehydes under reflux in methanol/ethanol. The structures of synthesized compounds were ascertained by elemental analysis and spectroscopic techniques. A comparative study of the antimicrobial activity and cytotoxicity was carried out of the N-protected amino acids, their esters, hydrazides, and the respective hydrazones, providing good results in cytotoxicity studies.
A new type of chiral-pyridoxamines for catalytic asymmetric transamination of α-keto acids
Chen, Jianfeng,Zhao, Junyu,Gong, Xing,Xu, Dongfang,Zhao, Baoguo
supporting information, p. 4612 - 4615 (2016/09/23)
A new type of chiral pyridoxamines bearing an adjacent chiral stereocenter has been developed via multi-step synthesis. The pyridoxamines displayed catalytic activity in asymmetric transamination of α-keto acids to give a variety of optically active amino acids in 27–78% yields with 34–62% ee's under very mild conditions. This work provides a synthetic strategy to construct new chiral pyridoxamines using bromopyridine 7 as a key synthon and also represents an early example of the applications of chiral pyridoxamines in asymmetric catalysis.
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.
Highly efficient dehydrogenative cross-coupling of aldehydes with amines and alcohols
Deshidi, Ramesh,Rizvi, Masood Ahmad,Shah, Bhahwal Ali
, p. 90521 - 90524 (2015/11/11)
A common protocol for the synthesis of amides, esters and α-ketoesters via cross dehydrogenative coupling of aldehydes and amines/alcohols has been developed. The method is applicable to a wide variety of alcohols and amines as well as aliphatic and aromatic aldehydes. Also, the use of acetaldehyde for acetylation and ethyl glyoxalate to access 2-oxo-amino esters is presented for the first time.
N-heterocyclic carbene-catalyzed oxidative amidation of aldehydes with amines
Alanthadka, Anitha,Maheswari, C. Uma
supporting information, p. 1199 - 1203 (2015/04/22)
The N-heterocyclic carbene (NHC)-catalyzed oxidative amidation of aromatic aldehydes with amines in the presence of N-bromosuccinimide (NBS) as an oxidant has been developed for the synthesis of amides. This amidation strategy is tolerant to both the electronic and the steric nature of the aryl aldehydes employed. The present methodology was extended to chiral amino acid derivatives to generate the corresponding amides in good yields and excellent ee values (>98%).
Peptide-catalyzed conversion of racemic oxazol-5(4 H)-ones into enantiomerically enriched α-amino acid derivatives
Metrano, Anthony J.,Miller, Scott J.
, p. 1542 - 1554 (2014/03/21)
We report the development and optimization of a tetrapeptide that catalyzes the methanolytic dynamic kinetic resolution of oxazol-5(4H)-ones (azlactones) with high levels of enantioinduction. Oxazolones possessing benzylic-type substituents were found to perform better than others, providing methyl ester products in 88:12 to 98:2 er. The mechanism of this peptide-catalyzed process was investigated through truncation studies and competition experiments. High-field NOESY analysis was performed to elucidate the solution-phase structure of the peptide, and we present a plausible model for catalysis.
