190377-29-8Relevant academic research and scientific papers
Imidazole analogues of resveratrol: Synthesis and cancer cell growth evaluation
Bellina, Fabio,Guazzelli, Nicola,Lessi, Marco,Manzini, Chiara
, p. 2298 - 2305 (2015)
Novel trans-restricted analogues of resveratrol in which the C-C double bond of the natural derivative has been replaced by diaryl substituted imidazole analogues have been designed. The syntheses of 1,4-, 2,4-, and 2,5-diarylimidazoles, in which the two
Regioselective C-H arylation of imidazoles employing macrocyclic palladium(II) complex of organoselenium ligand
Gadwal, Jitendra,Joshi, Hemant,Kumar, Sunil,Makar, Parvesh,Singh, Sohan
, (2021/06/12)
In this report we have presented synthesis of a new air stable bidentate selenium ligand (L1) by the reaction of 1,8-bis(2-(chloromethyl)phenoxy)octane with sodium salt of diphenyl diselenide. The reaction of bidentate selenium ligand (L1) with Pd(CH
Method for catalyzing direct arylation of imidazole compound by using palladium complex
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Paragraph 0047-0058, (2021/07/31)
The invention relates to a method for catalyzing direct arylation of an imidazole compound by using a palladium complex, which comprises the following steps: in the presence of alkali, taking the imidazole compound and aryl halide as raw materials, taking
Palladium-Based Catalysts Supported by Unsymmetrical XYC–1 Type Pincer Ligands: C5 Arylation of Imidazoles and Synthesis of Octinoxate Utilizing the Mizoroki–Heck Reaction
Maji, Ankur,Singh, Ovender,Singh, Sain,Mohanty, Aurobinda,Maji, Pradip K.,Ghosh, Kaushik
, p. 1596 - 1611 (2020/04/29)
A series of new unsymmetrical (XYC–1 type) palladacycles (C1–C4) were designed and synthesized with simple anchoring ligands L1–4H (L1H = 2-((2-(4-methoxybenzylidene)-1-phenylhydrazinyl)methyl)pyridine, L2H = N,N-dimethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazono)methyl)aniline, L3H = N,N-diethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazono)methyl) aniline and L4H = 4-(4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazono) methyl)phenyl)morpholine H = dissociable proton). Molecular structure of catalysts (C1–C4) were further established by single X-ray crystallographic studies. The catalytic performance of palladacycles (C1–C4) was explored with the direct Csp2–H arylation of imidazoles with aryl halide derivatives. These palladacycles were also applied for investigating of Mizoroki–Heck reactions with aryl halides and acrylate derivatives. During catalytic cycle in situ generated Pd(0) nanoparticles were characterized by XPS, SEM and TEM analysis and possible reaction pathways were proposed. The catalyst was employed as a pre-catalyst for the gram-scale synthesis of octinoxate, which is utilized as a UV-B sunscreen agent.
Palladium Complexes of Thio/Seleno-Ether Containing N-Heterocyclic Carbenes: Efficient and Reusable Catalyst for Regioselective C-H Bond Arylation
Bhatt, Ramprasad,Bhuvanesh, Nattamai,Sharma, Kamal Nayan,Joshi, Hemant
, p. 532 - 540 (2020/02/11)
The synthesis of the novel S,CNHC type half-pincer ligand precursors (L1 and L2) is described herein by using the atom economy reactions of 1-(2-(phenylthio)ethyl)-1H-imidazole with benzyl bromide and bromodiphenylmethane, respectively. The analogous reaction of 1-(2-(phenylselanyl)ethyl)-1H-imidazole with 2-bromoethyl phenyl sulfide has also resulted in a imidazolium bromide (L3) which is a precursor of novel S,CNHC,Se type pincer ligand. The route of silver-NHC transmetalation was employed to get the palladium complexes [Pd(L1/L2–HBr)Cl2] (C1 and C2) and [Pd(L3–HBr)Cl]BF4 (C3). The imidazolium bromide (L1–L3) and palladium complexes (C1–C3) were characterized by using multinuclear NMR and HR-MS. The structure and bonding in the complexes C1 and C2 were validated by X-ray crystallography. Thermally robust and moisture/air insensitive palladium complexes C1–C3 have been explored in the catalysis of C–H bond arylation of imidazoles. The protocol operates under mild reaction conditions in air with an excellent regioselective C–H bond arylation at C-5 position in imidazoles. All the complexes were found to be efficient (yield up to 97 % in 12 h) in the catalysis; however, the activating pincer ligand framework containing Pd catalyst C3, was found to be utmost effective among the three catalysts. Only 0.5 mol-% catalyst loading is required to achieve admirable yield of the desired cross-coupled products. A wide range of substrates was examined, and the developed protocol was applicable to all derivatives with high functional group tolerance and greater efficiency. More importantly, the catalyst C3 has also been found recyclable up to five cycles with minor decrease in efficiency which is highly desirable feature for the development of economical and sustainable industrial reaction processes. The PPh3 and Hg poisoning tests have established the complete homogeneous nature of the catalysis.
Palladium complexes of chalcogenoethanamine (S/Se) bidentate ligands: Applications in catalytic arylation of C[sbnd]H and O[sbnd]H bonds
Bhatt, Ramprasad,Bhuvanesh, Nattamai,Himanshi,Joshi, Hemant,Sharma, Alpesh K.
, (2020/05/18)
This report describes the syntheses of N,E (E = S, Se) coordinated bidentate palladium complexes, by the reaction of N-(2-bromobenzyl)-2-(phenylthio/selanyl)ethanamine (3, 4) with [PdCl2(CH3CN)2]. The new ligands and palladium complexes were characterized by techniques like 1H, 13C{1H} NMR, IR, and elemental analysis. The coordination modes of ligand with palladium precursor in complexes 5 and 6 were authenticated by single crystal X-ray diffraction. The complexes possess distorted square planar geometry around palladium center. Thermally robust and air stable complexes 5 and 6 were used as catalyst for regioselective arylation of imidazole and O-arylation of phenol. In case of regioselective arylation of imidazole, the reaction proceeds smoothly under mild reaction conditions, only 2.0 mol% of catalyst loading is required to achieve high yield (76–92%). This protocol is applicable to a broad substrate scope showing excellent tolerance towards different functional groups. Whereas for O-arylation of phenol also only 2.0 mol% catalyst loading is sufficient to give good yield (71–92%) with excellent tolerance towards a broad range of functional groups. Among sulfur and selenium coordinated ligands, selenium ligand coordinated complex, was found to outperform the catalytic reactions in both cases as compare to sulfur ligand. The mercury and triphenylphosphine poisoning tests suggest homogeneous nature of catalysis.
Imidazole-aryl coupling reaction via C[sbnd]H bond activation catalyzed by palladium supported on modified magnetic reduced graphene oxide in alkaline deep eutectic solvent
Shariatipour, Monire,Salamatmanesh, Arefe,Jadidi Nejad, Masoumeh,Heydari, Akbar
, (2019/11/20)
By employing reusable heterogeneous catalyst, modified magnetic reduced graphene oxide-supported palladium catalyst (MRGO@ DAP- AO-Pdll), the regioselective C-5 arylation of imidazoles via C[sbnd]H bond activation pathway for the preparation of
Computationally Driven Structure Optimization, Synthesis, and Biological Evaluation of Imidazole-Based Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) Inhibitors
Lammi, Carmen,Sgrignani, Jacopo,Arnoldi, Anna,Lesma, Giordano,Spatti, Claudia,Silvani, Alessandra,Grazioso, Giovanni
, p. 6163 - 6174 (2019/08/02)
Proprotein convertase subtilisin/kexin 9 (PCSK9) is responsible for the degradation of the hepatic low-density lipoprotein receptor (LDLR), which in turn regulates the circulating low-density lipoprotein cholesterol (LDL-C) level. For this reason, the PCSK9 inhibition, by small molecules or peptides, is a validated therapeutic approach for fighting hypercholesterolemia and cardiovascular diseases. In this field, we have recently reported an imidazole-based peptidomimetic that has shown PCSK9 inhibitory activity in the micromolar range. Here, by applying advanced computational techniques, the binding mechanism of that imidazole peptidomimetic was predicted. Then, among a small set of poly-imidazole analogs, compounds showing the highest theoretical affinity were suitably synthesized, relying on a van Leusen reaction based multicomponent strategy. One compound (named RIm13) displayed a PCSK9 inhibitory activity 10-fold lower than the template compound, and, remarkably, at a concentration of 1 μM, it successfully prevented the LDLR degradation mediated by PCSK9 on HepG2 cells. As well as increasing the LDL uptake at the same concentration, RIm13 represents currently one of the most potent small molecules targeting the PCSK9/LDLR protein-protein interaction.
Palladium(II) Complexes of N-Heterocyclic Carbene Amidates Derived from Chalcogenated Acetamide-Functionalized 1 H-Benzimidazolium Salts: Recyclable Catalyst for Regioselective Arylation of Imidazoles under Aerobic Conditions
Bhaskar, Renu,Sharma, Alpesh K.,Singh, Ajai K.
, p. 2669 - 2681 (2018/09/10)
The chalcogenated acetamide-functionalized 1H-benzimidazolium salt precursors [1-(CH2C(O)NH(CH2)2S/SePh)-3-R-C7H5N2]+ X (L1-L4; R = Me, CH2Ph; X = Br, I) to C,N,S/Se l
Developing Bis(imino)acenaphthene-Supported N-Heterocyclic Carbene Palladium Precatalysts for Direct Arylation of Azoles
Hu, Li-Qun,Deng, Rong-Li,Li, Yan-Fen,Zeng, Cui-Jin,Shen, Dong-Sheng,Liu, Feng-Shou
, p. 214 - 226 (2018/02/06)
On the basis of the strategy of developing highly efficient protocol for Pd-catalyzed cross-coupling reactions, a series of bulky bis(imino)acenaphthene (BIAN)-supported Pd-PEPPSI complexes were synthesized, characterized, and applied in direct arylation
