577-92-4Relevant academic research and scientific papers
Iron-Catalyzed Room Temperature Cross-Couplings of Bromophenols with Aryl Grignard Reagents
Xu, Li-Chen,Liu, Kun-Ming,Duan, Xin-Fang
supporting information, p. 5421 - 5427 (2019/11/14)
Herein we report a room temperature Fe-catalyzed coupling reaction of various bromophenols with aryl Grignard reagents, which exhibits a wide substrate scope and high functional group tolerance. For the first time, the combination of simple Fe(acac)3/PBu3/Ti(OEt)4 has been used as an effective catalyst for the biaryl couplings of bromophenols or their Na or K salts with debromination and etherification side reactions being well suppressed. Various biphenols including natural product garcibiphenyl C as well as pharmaceutical diflunisal and its ethyl ester were facilely synthesized using the present protocol. (Figure presented.).
Computer-Assisted Discovery and Structural Optimization of a Novel Retinoid X Receptor Agonist Chemotype
Heitel, Pascal,Gellrich, Leonie,Kalinowsky, Lena,Heering, Jan,Kaiser, Astrid,Ohrndorf, Julia,Proschak, Ewgenij,Merk, Daniel
, p. 203 - 208 (2019/01/25)
As universal heterodimer partners of many nuclear receptors, the retinoid X receptors (RXRs) constitute key transcription factors. They regulate cell proliferation, differentiation, inflammation, and metabolic homeostasis and have recently been proposed as potential drug targets for neurodegenerative and inflammatory diseases. Owing to the hydrophobic nature of RXR ligand binding sites, available synthetic RXR ligands are lipophilic, and their structural diversity is limited. Here, we disclose the computer-assisted discovery of a novel RXR agonist chemotype and its systematic optimization toward potent RXR modulators. We have developed a nanomolar RXR agonist with high selectivity among nuclear receptors and superior physicochemical properties compared to classical rexinoids that appears suitable for in vivo applications and as lead for future RXR-targeting medicinal chemistry.
Adiabatic deprotonation as an important competing pathway to ESIPT in photoacidic 2-phenylphenols
Mena, Leandro D.,Vera,Baumgartner, Maria T.,Jimenez, Liliana B.
, p. 12231 - 12240 (2019/06/20)
ESIPT (Excited State Intramolecular Proton Transfer) to C atom in 2-phenylphenol is known to be an intrinsically inefficient process. However, to the best of our knowledge, a structure-ESIPT efficiency relationship has not been elucidated yet. Here, we show that there exists a competitive interplay between photoacidity and ESIPT efficiency for the 2-phenylphenol system. The attachment of electron withdrawing groups to the phenol moiety promotes adiabatic deprotonation in the excited state and diminishes the charge transfer character of the excitations, and both these factors contribute in decreasing the ESIPT reaction yield. On the other hand, unfavorable conformational distribution in the ground state also appears as another important aspect responsible for the low ESIPT extent of 2-phenylphenol. A new derivative bearing electron donating, bulky substituents at ortho and para positions of the phenol ring shows an outstanding ESIPT performance, which demonstrates that the efficiency of the process can be significantly enhanced by modifying the substitution pattern. We anticipate that our results will help to guide the molecular designing of new compounds with high ESIPT efficiency.
Pseudocyclic Arylbenziodoxaboroles: Efficient Benzyne Precursors Triggered by Water at Room Temperature
Yoshimura, Akira,Fuchs, Jonathan M.,Middleton, Kyle R.,Maskaev, Andrey V.,Rohde, Gregory T.,Saito, Akio,Postnikov, Pavel S.,Yusubov, Mekhman S.,Nemykin, Victor N.,Zhdankin, Viktor V.
supporting information, p. 16738 - 16742 (2017/12/02)
New organohypervalent iodine compounds, arylbenziodoxaborole triflates, were prepared from 1-acetoxybenziodoxaboroles and arenes by treatment with trifluoromethanesulfonic acid under mild conditions. Single crystal X-ray crystallography of these compounds revealed a pseudocyclic structure with a short intramolecular interaction of 2.698 to 2.717 ? between oxygen and iodine in the benziodoxaborole ring. These new pseudocyclic aryliodonium salts readily generate aryne intermediates upon treatment with water at room temperature. The generated aryne intermediates react with various substrates to give the corresponding aryne adducts in moderate to good yields. Furthermore, the new benzyne precursors can also work as arylating reagents towards aromatic rings. The aryne intermediates generated from arylbenziodoxaborole triflates selectively react with tert-butyl phenol forming products of ortho arylation in moderate yields.
Copper-catalyzed selective ortho-arylations of 2-naphthol and phenol derivatives with diaryliodonium salts
Qian, Xiaofei,Han, Jianwei,Wang, Limin
, p. 607 - 610 (2016/01/20)
The selective arylations of 2-naphthol and phenol derivatives catalyzed by Cu(OTf)2 with using diaryliodonium(III) salts have been developed. With this method, biaryls bearing hydroxyl groups can be easily accessed in moderate to good yields. Additionally, this protocol provided an alternative for the preparation of 3-arylated binaphthalene derivatives.
DERIVATIVES OF 6-SUBSTITUTED TRIAZOLOPYRIDAZINES AS REV-ERB AGONISTS
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Page/Page column 43; 66, (2013/04/13)
The present invention provides novel 6-substituted [1,2,4]triazolo[4,3-b]pyridazines that are agonists of Rev-Erb. These compounds, and pharmaceutical compositions comprising the same, are suitable means for treating any disease wherein the activation of Rev-Erb has therapeutic effects, for instance in inflammatory and circadian rhythm-related disorders or cardiometabolic diseases.
Synthesis of dibenzopyranones through palladium-catalyzed directed C-H activation/carbonylation of 2-arylphenols
Luo, Shuang,Luo, Fei-Xian,Zhang, Xi-Sha,Shi, Zhang-Jie
supporting information, p. 10598 - 10601 (2013/10/21)
Dibenzopyranones were synthesized by a palladium-catalyzed phenol-directed C-H activation/carbonylation of 2-phenylphenol derivatives in the presence of CO. Pd(OAc)2 was used as a catalyst and Cu(OAc)2 as a catalytic oxidant in the presence of air. Copyright
Metal-free oxidative fluorination of phenols with [18F]fluoride
Gao, Zhanghua,Lim, Yee Hwee,Tredwell, Matthew,Li, Lei,Verhoog, Stefan,Hopkinson, Matthew,Kaluza, Wojciech,Collier, Thomas Lee,Passchier, Jan,Huiban, Mickael,Gouverneur, Véronique
supporting information; experimental part, p. 6733 - 6737 (2012/08/28)
The radiochemical synthesis of [18F]4-fluorophenols is based on phenol umpolung under oxidative conditions and direct nucleophilic fluorination with [18F]fluoride (see scheme, TBAF=tetra-n-butylammonium fluoride, TFA=trifluoroacetic acid). Readily available O-unprotected 4-tert-butyl phenols are used as precursors in this one-pot protocol. The reaction is completed in less than 30 minutes at room temperature and can be performed using standard or microfluidic technology. Copyright
Pd(II)-catalyzed C-H activation/aryl-aryl coupling of phenol esters
Xiao, Bin,Fu, Yao,Xu, Jun,Gong, Tian-Jun,Dai, Jian-Jun,Yi, Jun,Liu, Lei
supporting information; experimental part, p. 468 - 469 (2010/03/25)
(Chemical Equation Presented) Although nitrogen-containing group-directed cyclopalladation reactions have been well-known, Pd(II) insertion into C-H bonds promoted by coordination of an oxygen-only group to the palladium remains rather rare. In the present study, the first cyclopalladation complex formed from a simple phenol ester was characterized by X-ray crystallography. A promising protocol for the ortho C-H activation/aryl-aryl coupling of phenol esters that was not sensitive to moisture or air was then established. The utility of the reaction was demonstrated for the synthesis of useful phenol derivatives. Copyright
