29263-67-0Relevant articles and documents
Green synthesis method of polyaryl substituted methanol
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Paragraph 0127-0131; 0147-0151, (2021/04/17)
The invention relates to a green synthesis method of polyaryl substituted methanol, in particular to a method for efficiently synthesizing polyaryl substituted methanol in a polar aprotic solvent under the condition of an oxidizing agent by taking polyaryl substituted methane as a raw material and alkali as an additive. The method provided by the invention is green and environment-friendly, avoids using expensive metal catalysts, and has the advantages of low cost, few reaction steps, short time, high yield and the like.
Targeting the aryl hydrocarbon receptor with a novel set of triarylmethanes
Barigye, Stephen J.,Carpio, Laureano E.,Ferroud, Clotilde,Giner, Rosa M.,Goya-Jorge, Elizabeth,Gozalbes, Rafael,Loones, Nicolas,Rampal, Celine,Sylla-Iyarreta Veitía, Maité
supporting information, (2020/10/02)
The aryl hydrocarbon receptor (AhR) is a chemical sensor upregulating the transcription of responsive genes associated with endocrine homeostasis, oxidative balance and diverse metabolic, immunological and inflammatory processes, which have raised the pharmacological interest on its modulation. Herein, a novel set of 32 unsymmetrical triarylmethane (TAM) class of structures has been synthesized, characterized and their AhR transcriptional activity evaluated using a cell-based assay. Eight of the assayed TAM compounds (14, 15, 18, 19, 21, 22, 25, 28) exhibited AhR agonism but none of them showed antagonist effects. TAMs bearing benzotrifluoride, naphthol or heteroaromatic (indole, quinoline or thiophene) rings seem to be prone to AhR activation unlike phenyl substituted or benzotriazole derivatives. A molecular docking analysis with the AhR ligand binding domain (LBD) showed similarities in the binding mode and in the interactions of the most potent TAM identified 4-(pyridin-2-yl (thiophen-2-yl)methyl)phenol (22) compared to the endogenous AhR agonist 5,11-dihydroindolo[3,2-b]carbazole-12-carbaldehyde (FICZ). Finally, in silico predictions of physicochemical and biopharmaceutical properties for the most potent agonistic compounds were performed and these exhibited acceptable druglikeness and good ADME profiles. To our knowledge, this is the first study assessing the AhR modulatory effects of unsymmetrical TAM class of compounds.
Transition-Metal Free Chemoselective Hydroxylation and Hydroxylation-Deuteration of Heterobenzylic Methylenes
Fu, Yiwei,Li, Hao,Liu, Yonghai,Mang, Zhiguo,Shi, Lei,Sun, Chengyu,Yu, Yang
supporting information, p. 8127 - 8131 (2020/11/03)
We developed an approach for direct selective hydroxylation of heterobenzylic methylenes to secondary alcohols avoiding overoxidation to ketones by using a KOBu-t/DMSO/air system. Most reactions could reach completion in several minutes to give hydroxylated products in 41-76% yields. Using DMSO-d6, this protocol resulted in difunctionalization of heterobenzylic methylenes to afford α-deuterated secondary alcohols (>93% incorporation). By employing this method, active pharmaceutical ingredients carbinoxamine and doxylamine were synthesized in two steps in moderate yields.
Ligand-Free Iridium-Catalyzed Dehydrogenative ortho C?H Borylation of Benzyl-2-Pyridines at Room Temperature
Yang, Yuhuan,Gao, Qian,Xu, Senmiao
supporting information, p. 858 - 862 (2019/01/04)
A convenient and ligand-free iridium-catalyzed dehydrogenative ortho C?H borylation of benzyl-2-pyridines has been developed. The reaction proceeds smoothly at room temperature using pinacolborane as a borylating reagent in the presence of catalytic amount of [IrOMe(COD)]2. The reaction is compatible with many functional groups, providing a vast array of ortho borylated products in moderate to excellent yields with excellent selectivities. (Figure presented.).
Conformational Dynamics-Guided Loop Engineering of an Alcohol Dehydrogenase: Capture, Turnover and Enantioselective Transformation of Difficult-to-Reduce Ketones
Liu, Beibei,Qu, Ge,Li, Jun-Kuan,Fan, Wenchao,Ma, Jun-An,Xu, Yan,Nie, Yao,Sun, Zhoutong
, p. 3182 - 3190 (2019/05/15)
Directed evolution of enzymes for the asymmetric reduction of prochiral ketones to produce enantio-pure secondary alcohols is particularly attractive in organic synthesis. Loops located at the active pocket of enzymes often participate in conformational changes required to fine-tune residues for substrate binding and catalysis. It is therefore of great interest to control the substrate specificity and stereochemistry of enzymatic reactions by manipulating the conformational dynamics. Herein, a secondary alcohol dehydrogenase was chosen to enantioselectively catalyze the transformation of difficult-to-reduce bulky ketones, which are not accepted by the wildtype enzyme. Guided by previous work and particularly by structural analysis and molecular dynamics (MD) simulations, two key residues alanine 85 (A85) and isoleucine 86 (I86) situated at the binding pocket were thought to increase the fluctuation of a loop region, thereby yielding a larger volume of the binding pocket to accommodate bulky substrates. Subsequently, site-directed saturation mutagenesis was performed at the two sites. The best mutant, where residue alanine 85 was mutated to glycine and isoleucine 86 to leucine (A85G/I86L), can efficiently reduce bulky ketones to the corresponding pharmaceutically interesting alcohols with high enantioselectivities (～99% ee). Taken together, this study demonstrates that introducing appropriate mutations at key residues can induce a higher flexibility of the active site loop, resulting in the improvement of substrate specificity and enantioselectivity. (Figure presented.).
Iridium-Catalyzed Highly Enantioselective Transfer Hydrogenation of Aryl N-Heteroaryl Ketones with N-Oxide as a Removable ortho-Substituent
Liu, Qixing,Wang, Chunqin,Zhou, Haifeng,Wang, Baigui,Lv, Jinliang,Cao, Lu,Fu, Yigang
, p. 971 - 974 (2018/02/23)
A highly enantioselective transfer hydrogenation of non-ortho-substituted aryl N-heteroaryl ketones, using readily available chiral diamine-derived iridium complex (S,S)-1f as a catalyst and sodium formate as a hydrogen source in a mixture of H2O/i-PrOH (v/v = 1:1) under ambient conditions, is described. The chiral aryl N-heteroaryl methanols were obtained with up to 98.2% ee by introducing an N-oxide as a removable ortho-substituent. In contrast, no more than 15.1% ee was observed in the absence of an N-oxide moiety. Furthermore, the practical utility of this protocol was also demonstrated by gram-scale asymmetric synthesis of bepotastine besilate in 51% total yield and 99.9% ee.
Rhodium Catalyzed Asymmetric Hydrogenation of 2-Pyridine Ketones
Yang, Hailong,Huo, Ningning,Yang, Ping,Pei, Hao,Lv, Hui,Zhang, Xumu
, p. 4144 - 4147 (2015/09/15)
Catalyzed by [Rh(COD)Binapine]BF4, the asymmetric hydrogenation of 2-pyridine ketones has been achieved with excellent enantioselectivities (enantiomeric excesses up to 99%) under mild conditions. This method is suitable for various kinds of 2-pyridine ketones and their derivatives. A number of enantiomerically pure chiral 2-pyridine-aryl/alkyl alcohols were prepared through hydrogenation, which can be used directly in organic synthesis.
Iron-catalyzed C-H bond functionalization for the exclusive synthesis of pyrido[1,2-a]indoles or triarylmethanols
Karthikeyan, Iyyanar,Sekar, Govindasamy
supporting information, p. 8055 - 8063 (2015/01/09)
The efficient and selective iron-catalyzed C-H activation of 2-benzhydrylpyridine derivatives was employed for the preparation of pyrido[1,2-a]indoles through an intramolecular C-H amination reaction. In the presence of molecular oxygen as the sole oxidant, the same 2-benzhydrylpyridines were also used for the synthesis of the corresponding tertiary alcohols. In these approaches, the iron catalyst was used to selectively activate the C(sp2)-H bond of 2-benzhydrylpyridine, in the case of the intramolecular ring-closing C-H amination reaction in which the pyridine nitrogen atom was a directing group as well as a nucleophile, and the C(sp3)-H bond of the same compound, in the case of the oxidation reaction to give the corresponding triaryl carbinol.
Facile one-pot synthesis of [1,2,3]triazolo[1,5-a]pyridines from 2-acylpyridines by copper(II)-catalyzed oxidative N-N bond formation
Hirayama, Tasuku,Ueda, Satoshi,Okada, Takahiro,Tsurue, Norihiko,Okuda, Kensuke,Nagasawa, Hideko
supporting information, p. 4156 - 4162 (2014/04/17)
An efficient and simple method for the synthesis of various [1,2,3]triazolo[1,5-a]pyridines has been established. The method involves a copper(II)-catalyzed oxidative N-N bond formation that uses atmospheric oxygen as the terminal oxidant following hydrazonation in one pot. The use of ethyl acetate as the solvent dramatically promotes the oxidative N-N bond-formation reaction and enables the application of oxidative cyclization in the efficient one-pot reaction. A mechanism for the reaction was proposed on the basis of the results of a spectroscopic study. In the same pot: [1,2,3]Triazolo[1,5-a] pyridines are synthesized from the corresponding 2-acylpyridines by a one-pot method, consisting of hydrazonation followed by oxidative cyclization through copper(II)-catalyzed N-N bond formation (see scheme).
Effective dehydrogenation of 2-pyridylmethanol derivatives catalyzed by an iron complex
Kamitani, Masahiro,Ito, Masaki,Itazaki, Masumi,Nakazawa, Hiroshi
supporting information, p. 7941 - 7944 (2014/07/08)
An unprecedented iron complex-catalyzed dehydrogenation of alcohols was achieved using CpFe(CO)2Cl with a base or CpFe(CO)(Py)(Ph) as a catalyst without sacrificing the hydrogen acceptors. This reaction effectively (up to TON 67000) converted 2-pyridylmethanol derivatives to the corresponding ketones or aldehydes. The mechanistic study is also discussed. the Partner Organisations 2014.
