140653-89-0Relevant academic research and scientific papers
Asymmetric Construction of α-Substituted β-Hydroxy Lactones via Ni Catalyzed Decarboxylative Addition Reaction
He, Lingchen,Ahmed, Ebrahim-Alkhalil M. A.,Liu, Hongxin,Hu, Xingen,Xiao, Hong-Ping,Li, Juan,Jiang, Jun
, p. 4825 - 4834 (2021/04/02)
We described a Ni-bidentate oxazoline catalyzed highly enantio- and diastereoselective decarboxylative aldol reaction of 2-oxotetrahydrofuran-3-carboxylic acid/2-oxochromane-3-carboxylic acid derivatives with different kinds of carbonyls. Under optimal reaction conditions, α-substituted β-hydroxy butyrolactones and dihydrocoumarins with an all-carbon quaternary stereocenter have been generated with high levels of functional-group compatibility. Furthermore, proficient transformations of products were also described, in which an aliphatic tertiary alcohol and a multi-substituted 1,4-diol were smoothly constructed through hydrogenation and ring-opening reaction, respectively.
Stereo- and Regioselective [3+3] Annulation Reaction Catalyzed by Ytterbium: Synthesis of Bicyclic 1,4-Dihydropyridines
del Corte, Xabier,López-Francés, Adrián,de Marigorta, Edorta Martínez,Palacios, Francisco,Vicario, Javier
supporting information, p. 4761 - 4769 (2021/08/23)
An ytterbium catalyzed formal [3+3] cycloaddition of cyclic enamines and α,β-unsaturated ketones catalyzed is reported. The reaction proceeds with a ‘head to tail’ regioselectivity through a conjugate addition of the enamine moiety followed by an amine-carbonyl condensation. In addition the use of chiral enamines provided a high degree of stereoselectivity, driven by a possible balance between steric and π-stacking effects. The resulting bicyclic 1,4-dihydropyridines were evaluated as antiproliferative agents against A549 (carcinomic human alveolar basal epithelial cell) and SKOV3 (human ovarian carcinoma) human tumor cell lines. Good toxicities were found for some of the compounds against A549 and SKOV3 cell lines, with best IC50 values of 0.89 μM for A549 and 6.69 μM for SKOV3, and a very good selectivity was observed towards MRC5 (non-malignant) cell lines. (Figure presented.).
Structure-Activity Relationship Studies of α-Ketoamides as Inhibitors of the Phospholipase A and Acyltransferase Enzyme Family
Zhou, Juan,Mock, Elliot D.,Al Ayed, Karol,Di, Xinyu,Kantae, Vasudev,Burggraaff, Lindsey,Stevens, Anna F.,Martella, Andrea,Mohr, Florian,Jiang, Ming,Van Der Wel, Tom,Wendel, Tiemen J.,Ofman, Tim P.,Tran, Yvonne,De Koster, Nicky,Van Westen, Gerard J.P.,Hankemeier, Thomas,Van Der Stelt, Mario
, p. 9340 - 9359 (2020/10/19)
The phospholipase A and acyltransferase (PLAAT) family of cysteine hydrolases consists of five members, which are involved in the Ca2+-independent production of N-acylphosphatidylethanolamines (NAPEs). NAPEs are lipid precursors for bioactive N-acylethanolamines (NAEs) that are involved in various physiological processes such as food intake, pain, inflammation, stress, and anxiety. Recently, we identified α-ketoamides as the first pan-active PLAAT inhibitor scaffold that reduced arachidonic acid levels in PLAAT3-overexpressing U2OS cells and in HepG2 cells. Here, we report the structure-activity relationships of the α-ketoamide series using activity-based protein profiling. This led to the identification of LEI-301, a nanomolar potent inhibitor for the PLAAT family members. LEI-301 reduced the NAE levels, including anandamide, in cells overexpressing PLAAT2 or PLAAT5. Collectively, LEI-301 may help to dissect the physiological role of the PLAATs.
Bimetallic Catalytic Asymmetric Tandem Reaction of β-Alkynyl Ketones to Synthesize 6,6-Spiroketals
Ge, Shulin,Cao, Weidi,Kang, Tengfei,Hu, Bowen,Zhang, Hang,Su, Zhishan,Liu, Xiaohua,Feng, Xiaoming
supporting information, p. 4017 - 4021 (2019/02/26)
The enantioselective tandem reaction of β,γ-unsaturated α-ketoesters with β-alkynyl ketones was realized by a bimetallic catalytic system of achiral AuΙΙΙ salt and chiral N,N′-dioxide-MgΙΙ complex. The cycloisomerization of β-alkynyl ketone and asymmetric intermolecular [4+2] cycloaddition with β,γ-unsaturated α-ketoesters subsequently occurred, providing an efficient and straightforward access to chiral multifunctional 6,6-spiroketals in up to 97 % yield, 94 % ee and >19/1 d.r. Besides, a catalytic cycle was proposed based on the results of control experiments.
Asymmetric Catalytic Formal 1,4-Allylation of β,γ-Unsaturated α-Ketoesters: Allylboration/Oxy-Cope Rearrangement
Tang, Qiong,Fu, Kai,Ruan, Peiran,Dong, Shunxi,Su, Zhishan,Liu, Xiaohua,Feng, Xiaoming
supporting information, p. 11846 - 11851 (2019/07/19)
A highly enantioselective formal conjugate allyl addition of allylboronic acids to β,γ-unsaturated α-ketoesters has been realized by employing a chiral NiII/N,N′-dioxide complex as the catalyst. This transformation proceeds by an allylboration/oxy-Cope rearrangement sequence, providing a facile and rapid route to γ-allyl-α-ketoesters with moderate to good yields (65–92 %) and excellent ee values (90–99 % ee). The isolation of 1,2-allylboration products provided insight into the mechanism of the subsequent oxy-Cope rearrangement reaction: substrate-induced chiral transfer and a chiral Lewis acid accelerated process. Based on the experimental investigations and DFT calculations, a rare boatlike transition-state model is proposed as the origin of high chirality transfer during the oxy-Cope rearrangement.
Potassium 2-oxo-3-enoates as Effective and Versatile Surrogates for α, β-Unsaturated Aldehydes in NHC-Catalyzed Asymmetric Reactions
Gao, Yaru,Ma, Yafei,Xu, Chen,Li, Lin,Yang, Tianjian,Sima, Guoqing,Fu, Zhenqian,Huang, Wei
supporting information, p. 479 - 484 (2017/12/26)
Potassium 2-oxo-3-enoates, which are readily prepared at scale and easily stored, have been found to be effective and versatile surrogates for α,β-unsaturated aldehydes in NHC-catalyzed asymmetric reactions. Promoted by chiral N-heterocyclic carbenes combined with LiCl, these easy-to-handle solid salts could release of CO2 and then undergo asymmetric reactions via homoenolate and α, β-unsaturated acyl azolium intermediate. The reactions have broad substrate scopes with high enantioselectivities. (Figure presented.).
Facile synthesis of substituted diaryl sulfones: Via a [3 + 3] benzannulation strategy
Tang, Xiang-Zheng,Tong, Lang,Liang, Hua-Ju,Liang, Jie,Zou, Yong,Zhang, Xue-Jing,Yan, Ming,Chan, Albert S. C.
supporting information, p. 3560 - 3563 (2018/05/26)
A base-mediated [3 + 3] benzannulation strategy for the conversion of 1,3-bis(sulfonyl)propenes and β,γ-unsaturated α-ketoesters to diaryl sulfones has been developed. This method provides facile, metal-free and efficient access to highly substituted diaryl sulfones in good to excellent yields. In addition, the sulfonyl group could be easily removed or converted to other functional groups via an organostannane intermediate.
Enantioselective NHC-catalysed redox [4+2]-hetero-Diels-Alder reactions using α-aroyloxyaldehydes and unsaturated ketoesters
Taylor, James E.,Davies, Alyn T.,Douglas, James J.,Churchill, Gwydion,Smith, Andrew D.
, p. 355 - 366 (2017/02/15)
N-Heterocyclic carbene (NHC)-catalysed redox [4+2]-hetero-Diels-Alder reactions of α-aroyloxyaldehydes with either β,γ-unsaturated α-ketoesters or α,β-unsaturated γ-ketoesters generates substituted syn-dihydropyranones in good yield with excellent enantioselectivity (up to >99:1 er). The product diastereoselectivity is markedly dependent upon the nature of the unsaturated enone substituent. The presence of either electron-neutral or electron-rich aryl substituents gives excellent diastereoselectivity (up to >99:5 dr), while electron-deficient aryl substituents give reduced diastereoselectivity. In these cases, the syn-dihydropyranone products are more susceptible to base-promoted epimerisation at the C(4)-position under the reaction conditions, accounting for the lower diastereoselectivity obtained.
Boosting Chemical Stability, Catalytic Activity, and Enantioselectivity of Metal-Organic Frameworks for Batch and Flow Reactions
Chen, Xu,Jiang, Hong,Hou, Bang,Gong, Wei,Liu, Yan,Cui, Yong
supporting information, p. 13476 - 13482 (2017/10/05)
A key challenge in heterogeneous catalysis is the design and synthesis of heterogeneous catalysts featuring high catalytic activity, selectivity, and recyclability. Here we demonstrate that high-performance heterogeneous asymmetric catalysts can be engineered from a metal-organic framework (MOF) platform by using a ligand design strategy. Three porous chiral MOFs with the framework formula [Mn2L(H2O)2] are prepared from enantiopure phosphono-carboxylate ligands of 1,1′-biphenol that are functionalized with 3,5-bis(trifluoromethyl)-, bismethyl-, and bisfluoro-phenyl substituents at the 3,3′-position. For the first time, we show that not only chemical stability but also catalytic activity and stereoselectivity of the MOFs can be tuned by modifying the ligand structures. Particularly, the MOF incorporated with -CF3 groups on the pore walls exhibits enhanced tolerance to water, weak acid, and base compared with the MOFs with -F and -Me groups. Under both batch and flow reaction systems, the CF3-containing MOF demonstrated excellent reactivity, selectivity, and recyclability, affording high yields and enantioselectivities for alkylations of indoles and pyrrole with a range of ketoesters or nitroalkenes. In contrast, the corresponding homogeneous catalysts gave low enantioselectivity in catalyzing the tested reactions.
Efficient enantioselective synthesis of dihydropyrans using a chiral N, N ′-dioxide as organocatalyst
Feng, Juhua,Fu, Xuan,Chen, Zhenling,Lin, Lili,Liu, Xiaohua,Feng, Xiaoming
supporting information, p. 2640 - 2643 (2013/07/19)
The bifunctional organocatalyst C3 N,N′-dioxide has been successfully applied to the asymmetric cascade Michael/hemiacetalization reaction of α-substituted cyano ketones and β,γ-unsaturated α-ketoesters for the synthesis of multifunctionalized chiral dihydropyrans. The corresponding products were obtained in excellent yields (up to 99%) with high to excellent enantioselectivities (up to 99% ee).
