3988-77-0Relevant articles and documents
Potassium Base-Catalyzed Michael Additions of Allylic Alcohols to α,β-Unsaturated Amides: Scope and Mechanistic Insights
Kurouchi, Hiroaki,Sai, Masahiro
supporting information, p. 3585 - 3591 (2021/06/27)
We report herein the first KHMDS-catalyzed Michael additions of allylic alcohols to α,β-unsaturated amides through allylic isomerization. The reaction proceeds smoothly in the presence of only 5 mol% of KHMDS to afford a variety of 1,5-ketoamides in high yields. Mechanistic investigations, including experimental and computational studies, reveal that the KHMDS-catalyzed in-situ generation of the enolate from the allylic alcohol through a tunneling-assisted 1,2-hydride shift is the key to the success of this transformation. (Figure presented.).
Potassium Base-Promoted Diastereoselective Synthesis of 1,3-Diols from Allylic Alcohols and Aldehydes through a Tandem Allylic-Isomerization/Aldol–Tishchenko Reaction
Sai, Masahiro
supporting information, p. 4053 - 4056 (2021/10/25)
This study reports the first base-promoted aldol–Tishchenko reactions of allylic alcohols with aldehydes initiated by allylic isomerization. The reaction enables the diastereoselective synthesis of a variety of 1,3-diols with three contiguous stereogenic centers. Unlike commonly reported systems, our method allows the use of readily available allylic alcohols as nucleophiles instead of enolizable aldehydes and ketones.
Facile Synthesis of Polysubstituted 2-Pyrones via TfOH-Mediated Ring Expansion of 2-Acylcyclopropane-1-carboxylates
Shao, Jiru,An, Caiyun,Wang, Sunewang R.
, p. 4030 - 4041 (2021/07/19)
A facile route to polysubstituted 2-pyrones from readily available 2-acylcyclopropane-1-aryl-1-carboxylates mediated by TfOH is reported. The strongly donating 1-aryl group is important for directing the C-C bond cleavage of the donor-acceptor cyclopropane ring, which then leads to the formation of the 2-pyrone ring through lactonization.
Heteroleptic copper(I) complexes as energy transfer photocatalysts for the intermolecular [2 + 2] photodimerization of chalcones, cinnamates and cinnamamides
Wu, Qing-An,Ren, Chen-Chao,Chen, Feng,Wang, Tian-Qi,Zhang, Yu,Liu, Xue-Fen,Chen, Jian-Bin,Luo, Shu-Ping
supporting information, (2021/05/10)
The [2 + 2] photodimerization of chalcones, cinnamates and cinnamamides can be effectively catalyzed by heteroleptic copper(I) complexes. The reactions were carried out under mild reaction conditions and the products were obtained in 20–72% yield under visible light irradiation. The copper-based photocatalyst comprised of the rigid phenanthroline ligand with substituents at the 2,9-positions and the 4,7-positions showed high activity in the photodimerization via an energy transfer pathway.
Green method for high-selectivity synthesis of chalcone compounds
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Paragraph 0103-0106, (2021/10/02)
Under the condition of air, the water-soluble inorganic weak base is used as a catalyst to catalyze the hydrogen transfer reaction of the propargyl alcohol compound, so that the green synthesis of the high-trans selective chalcone compound is realized. Reaction temperature: 80 - 120 °C and reaction time 12 - 48 hours. To the technical scheme, any transition metal catalyst and ligand do not need to be used, inert gas protection is not needed, no other byproducts are generated, the atom economy 100%, green and environment friendliness are avoided, and the product is a high-selectivity (E)-type product. The reaction conditions are relatively low in requirement. Compared with the prior art, the alkali catalyst is obvious in advantages, and has a certain application prospect in the fields of organic synthesis, biochemistry, medicine and the like.
Apoptosis: A target for anticancer therapy with novel cyanopyridines
Ismail, Magda M.F.,Farrag, Amel M.,Harras, Marwa F.,Ibrahim, Mona H.,Mehany, Ahmed B.M.
, (2019/12/25)
One of the many methods of treating cancer is to terminate the uncontrolled growth of cancer cells. So, aiming the apoptotic pathway is an exciting approach to finding new anticancer agents. A novel series of cyanopyridines was designed and synthesized for antiproliferative evaluation. 2-Amino-6-(4-(benzyloxy)phenyl)-4-(4-(dimethylamino)phenyl) nicotinonitrile 10f was the most potent inhibitor against the growth of PC-3, and HepG-2 cancer cell lines with IC50 values of 2.04 uM (selectivity index, SI = 78.63, 43, respectively). Also, 10f was safe against the growth of normal human diploid lung fibroblasts cell line (WI-38) with an IC50 value of 160.04 uM. Its analogs, 10b, 10d, 10g, and 11b, were also active against the growth of PC-3, and HepG-2 while against MCF-7 cell line, they displayed good cytotoxic activity compared to the reference standard 5-FU. Remarkably, mechanistic studies indicated that compounds 10b, 10d, 10f, 10g, and 11b stimulated the level of active caspase 3 and boosted the BAX/BCL2 ratio 20–95 folds in comparison to the control. Our results have also indicated that 10b, 10d, 10f, 10g, and 11b exhibited a very potent inhibitory activity against PIM-1 kinase enzyme, where the IC50 values unraveled very potent molecules in the micromolar range (0.47–1.27 μM). Further investigations have shown that 10f, the most potent PIM-1 kinase inhibitor, induced a cell cycle arrest at the G2/M phase. Moreover, in silico evaluation of ADME properties indicated that all the cyanopyridine compounds are orally bioavailable with no permeation to the blood brain barrier.
N-para-sulfonium salt substituted pyrazoline derivative, photocurable composition and preparation method
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Paragraph 0148-0149; 0167-0169; 0173-0174, (2020/07/21)
The invention relates to an N-para-sulfonium salt substituted pyrazoline derivative shown as the following formula (I) in the specification, a photocurable composition, and a preparation method of theN-para-sulfonium salt substituted pyrazoline derivative shown as the following formula (I). The N-para-sulfonium salt substituted pyrazoline derivative shown as formula (I) has good absorption at a wavelength of 350nm or above, and compared with a 5-substituted sulfonium salt, the N-para-sulfonium salt substituted pyrazoline derivative has the advantages of simpler and more convenient molecule synthesis steps and reduced cost of raw materials, and is more suitable for industrial production and application.
DBU-Catalyzed Rearrangement of Secondary Propargylic Alcohols: An Efficient and Cost-Effective Route to Chalcone Derivatives
De, Rimpa,Savarimuthu, Antony,Ballav, Tamal,Singh, Pijush,Nanda, Jayanta,Hasija, Avantika,Chopra, Deepak,Bera, Mrinal K.
, p. 1587 - 1592 (2020/08/28)
A 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-catalyzed rearrangement of diarylated secondary propargylic alcohols to give α,β-unsaturated carbonyl compounds has been developed. The typical 1,3-transposition of oxy functionality, characteristic of Mayer-Schuster rearrangements, is not observed in this case. A broad substrate scope, functional-group tolerance, operational simplicity, complete atom economy, and excellent yields are among the prominent features of the reaction. Additionally, the photophysical properties and crystal-structure-packing behavior of selected compounds were investigated and found to be of interest.
Application of Polyphosphoric Acid-Mediated Acyl Migration for Regiospecific Synthesis of Diverse 2-Acylpyrroles from Chalcones
Kumar, Togiti Uday,Thigulla, Yadagiri,Rangan, Krishnan,Bhattacharya, Anupam
supporting information, p. 1283 - 1290 (2019/03/07)
A metal-free approach for the synthesis of 2-acylpyrroles is reported in this paper. Synthesis of the target molecule started from chalcones and was carried out in two steps. Initial step involved the conversion of chalcones to corresponding 4-substituted-3-acylpyrroles by reaction with TosMIC. In the subsequent step, target molecules were obtained in modest to good yields by polyphosphoric acid-mediated acyl rearrangement of 3-acylpyrroles to their 2-acyl congeners. The crucial final step was amenable to diverse substitutions on pyrrole ring. Preliminary experiment for the determination of mechanism indicated the involvement of acylium ion.
Electrochemical 1,4-reduction of α,β-unsaturated ketones with methanol and ammonium chloride as hydrogen sources
Huang, Binbin,Li, Yanan,Yang, Chao,Xia, Wujiong
supporting information, p. 6731 - 6734 (2019/06/17)
A sustainable, chemoselective 1,4-reduction of α,β-unsaturated ketones by means of an electrochemical method is presented, wherein the extremely inexpensive ammonium chloride (NH4Cl) is applied as the only additive. The reaction proceeds smoothly in the air at ambient temperature. Mechanistic studies reveal that both NH4Cl and solvent methanol work as hydrogen donors.
