10229-22-8Relevant academic research and scientific papers
Lipase-catalyzed aminolysis and ammonolysis of β-ketoesters. Synthesis of optically active β-ketoamides.
Garcia,Rebolledo,Gotor
, p. 6935 - 6940 (1994)
Aminolysis and ammonolysis reactions of β-ketoesters catalyzed by Candida antarctica lipase are very efficient methods for the preparation of β- ketoamides. When racemic amines are used in these processes, the corresponding optically active β-ketoamides are obtained with moderate-high enantiomeric excesses.
Chiral Vanadyl(V) Complexes Enable Efficient Asymmetric Reduction of β-Ketoamides: Application toward (S)-Duloxetine
Chen, Chien-Tien,Maity, Nabin Ch.,Agarwal, Rachit,Lai, Chien-Fu,Liao, Yiya,Yu, Wei-Ru
supporting information, p. 6408 - 6419 (2020/07/14)
High-valent chiral oxidovanadium(V) complexes derived from 3,5-substituted-N-salicylidene-l-tert-leucine were used as catalysts in asymmetric reduction of N-benzyl-β-ketoamides. Among six different solvents, three different alcohol additives, and two different boranes examined, the use of pinacolborane in tetrahydrofuran (THF) with a t-BuOH additive led to the best results at -20 °C. The corresponding β-hydroxyamides can be furnished with yields up to 92percent and an enantiomeric excess (ee) up to 99percent. We have successfully extended this catalytic protocol for the synthesis of an (S)-duloxetine precursor.
Design, Synthesis, and Biochemical Characterization of Non-Native Antagonists of the Pseudomonas aeruginosa Quorum Sensing Receptor LasR with Nanomolar IC50 Values
Blackwell, Helen E.,Manson, Daniel E.,Nyffeler, Kayleigh E.,O'Reilly, Matthew C.
, (2020/03/04)
Quorum sensing (QS), a bacterial cell-to-cell communication system mediated by small molecules and peptides, has received significant interest as a potential target to block infection. The common pathogen Pseudomonas aeruginosa uses QS to regulate many of its virulence phenotypes at high cell densities, and the LasR QS receptor plays a critical role in this process. Small molecule tools that inhibit LasR activity would serve to illuminate its role in P. aeruginosa virulence, but we currently lack highly potent and selective LasR antagonists, despite considerable research in this area. V-06-018, an abiotic small molecule discovered in a high-throughput screen, represents one of the most potent known LasR antagonists but has seen little study since its initial report. Herein, we report a systematic study of the structure-activity relationships (SARs) that govern LasR antagonism by V-06-018. We synthesized a focused library of V-06-018 derivatives and evaluated the library for bioactivity using a variety of cell-based LasR reporter systems. The SAR trends revealed by these experiments allowed us to design probes with 10-fold greater potency than that of V-06-018 and 100-fold greater potency than other commonly used N-acyl-l-homoserine lactone (AHL)-based LasR antagonists, along with high selectivities for LasR. Biochemical experiments to probe the mechanism of antagonism by V-06-018 and its analogues support these compounds interacting with the native ligand-binding site in LasR and, at least in part, stabilizing an inactive form of the protein. The compounds described herein are the most potent and efficacious antagonists of LasR known and represent robust probes both for characterizing the mechanisms of LuxR-type QS and for chemical biology research in general in the growing QS field.
Catalytic Asymmetric Epoxidation of Aldehydes with Two VANOL-Derived Chiral Borate Catalysts
Gupta, Anil K.,Yin, Xiaopeng,Mukherjee, Munmun,Desai, Aman A.,Mohammadlou, Aliakbar,Jurewicz, Kelsee,Wulff, William D.
supporting information, p. 3361 - 3367 (2019/02/16)
A highly diastereo- and enantioselective method for the epoxidation of aldehydes with α-diazoacetamides has been developed with two different borate ester catalysts of VANOL. Both catalytic systems are general for aromatic, aliphatic, and acetylenic aldehydes, giving high yields and inductions for nearly all cases. One borate ester catalyst has two molecules of VANOL and the other only one VANOL. Catalysts generated from BINOL and VAPOL are ineffective catalysts. An application is shown for access to the side-chain of taxol.
Multicomponent strategy to indeno[2,1- C ]pyridine and hydroisoquinoline derivatives through cleavage of carbon-carbon bond
Feng, Xian,Wang, Jian-Jun,Xun, Zhan,Huang, Zhi-Bin,Shi, Da-Qing
, p. 1025 - 1033 (2015/01/30)
A concise and efficient three-component domino reaction has been developed for the synthesis of polyfunctionalized indenopyridine and hydroisoquinoline derivatives via the cleavage of a C-C bond under transition-metal-free conditions. This reaction provides facile access to complex nitrogen-containing heterocycles by simply mixing three common starting materials in EtOH in the presence of 20 mol % NaOH under microwave irradiation conditions.
Palladium-catalyzed c-S activation/aryne insertion/coupling sequence: Synthesis of functionalized 2-quinolinones
Dong, Ying,Liu, Bangyu,Chen, Peng,Liu, Qun,Wang, Mang
supporting information, p. 3442 - 3446 (2014/04/03)
The insertion of an aryne into a C-S bond can suppress the addition of an S nucleophile to the aryne in the presence of palladium. Catalyzed by Pd(OAc)2, a wide range of α-carbamoyl ketene dithioacetals readily react with arynes to selectively afford functionalized 2-quinolinones in high yields under neutral reaction conditions by a C-S activation/aryne insertion/intramolecular coupling sequence. The attractive feature of the new strategy also lies in the versatile transformations of the alkythio-substituted quinolinone products. Within range: Under palladium catalysis a wide range of α-carbamoyl ketene dithioacetals readily react with arynes to selectively afford 2-quinolinones in high yields under neutral reaction conditions by the title sequence (see scheme). An attractive feature of the new strategy also lies in the versatile transformations of the alkylthio-substituted quinolinones.
Copper-Catalyzed Aerobic Oxidations of 3-N-Hydoxyaminoprop-1-ynes to Form 3-Substituted 3-Amino-2-en-1-ones: Oxidative Mannich Reactions with a Skeletal Rearrangement
Kawade, Rahul Kisan,Tseng, Chang-Chin,Liu, Rai-Shung
, p. 13927 - 13931 (2016/02/18)
Cu-catalyzed aerobic oxidations of readily available 3-N-hydroxyaminopro-1-ynes with water, alcohols, or thiols to form diverse 3-substituted 3-amino-2-en-1-ones are described. The utility of this catalysis is manifested by a wide scope of applicable N-hydroxyl propargylamines and nucleophiles, thus enabling the design of one-pot cascade or two-step sequential reactions. Besides synthetic significances, such oxidative Mannich reactions are mechanistically interesting because structurally reorganized products were obtained. Our mechanistic studies reveal that the aerobic oxidations involve initial formation of nitrone intermediates, followed by the attack of nucleophiles. Herein, water and MeOH implement the conversion of nitrone intermediates to reaction products in two distinct pathways. Go Mannich! Cu-catalyzed aerobic oxidations of 3-N-hydroxyaminopro-1-ynes with water, alcohols, or thiols to form diverse 3-substituted 3-amino-2-en-1-ones are reported (see scheme). Such oxidative Mannich reactions are mechanistically interesting, because structurally reorganized products were obtained.
Highly enantioselective epoxidation catalyzed by cinchona thioureas: Synthesis of functionalized terminal epoxides bearing a quaternary stereogenic center
Russo, Alessio,Galdi, Gerardina,Croce, Gianluca,Lattanzi, Alessandra
supporting information; experimental part, p. 6152 - 6157 (2012/06/30)
A brilliant debut! Cinchona thioureas have been reported for the first time as catalysts in the area of asymmetric oxidations. They efficiently promote an unprecedented highly enantioselective epoxidation of deactivated 1,1-disubstituted alkenes to terminal epoxides containing a quaternary stereogenic center (see scheme). Copyright
Efficient regioselective heterocyclisation leading to fluorescent fused pyrazine derivatives
Ostrowska, Katarzyna,Szymoniak, Katarzyna,Szczurek, Magdalena,Jamrozy, Krzysztof,Ra?pa?a-Kozik, Maria
experimental part, p. 5219 - 5227 (2011/07/31)
The regioselective syntheses of substituted pyrrolo[2,3-b]quinoxaline, pyrido[2,3-b]pyrrolo[2,3-e]pyrazine, pyrido[2,3-b]pyrrolo[3,2-e]pyrazine and pyrido[3,4-b]pyrrolo[3,2-e]pyrazine are reported. Differential reactivity between two amino groups in ortho-diaminopyridine can be exploited to obtain new regio-defined unsymmetrical pyridopyrrolopyrazine derivatives. Weak electron-donating methyl or moderately electron-withdrawing carboxylic groups attached to the aromatic ortho-diamines reduce the regioselectivity of obtaining unsymmetrical substituted pyrrolo[2,3-b]quinoxaline. The fluorescence properties of the resultant 1-alkyl pyridopyrrolopyrazine and substituted pyrrolo[2,3-b]quinoxaline derivatives are presented.
A new synthesis of β-keto amides by reduction of Passerini adducts
Neo, Ana G.,Delgado, Jose,Polo, Cecilia,Marcaccini, Stefano,Marcos, Carlos F.
, p. 23 - 26 (2007/10/03)
The Passerini reaction between glyoxals, isocyanides and acetic acid forms β-keto acyloxyamides, which are readily transformed in β-keto amides by reductive deacetoxylation with zinc. The versatility of this procedure, which allows introducing different groups both in position-3 and the amide nitrogen, makes it ideal for its use in diversity-oriented synthesis, in combination with subsequent complexity generation reactions.
