25726-04-9Relevant academic research and scientific papers
A Cooperative Ternary Catalysis System for Asymmetric Lactonizations of α-Ketoesters
Murauski, Kathleen J. R.,Walden, Daniel M.,Cheong, Paul Ha-Yeon,Scheidt, Karl A.
, p. 3713 - 3719 (2017)
A general and enantioselective N-heterocyclic carbene (NHC)-catalyzed lactonization of simple enals and α-ketoesters has been discovered using a new ternary cooperative catalytic system. The highly selective annulation was achieved by using a combination of a chiral NHC, a hydrogen-bond donor, and a metal salt, facilitating self-assembly of the reactive partners. A proposed model for this new mode of NHC chiral relay catalysis is supported by experimental and computational mechanistic studies. (Figure presented.).
C?H Insertion as a Key Step to Spiro-Oxetanes, Scaffolds for Drug Discovery
Nicolle, Simon M.,Nortcliffe, Andrew,Bartrum, Hannah E.,Lewis, William,Hayes, Christopher J.,Moody, Christopher J.
, p. 13623 - 13627 (2017)
A new route to spiro-oxetanes, potential scaffolds for drug discovery, is described. The route is based on the selective 1,4-C?H insertion reactions of metallocarbenes, generated from simple carbonyl precursors in flow or batch mode, to give spiro-β-lacto
Crystallization-induced diastereomer transformation of thiohydantoin derivatives
Mino, Takashi,Sakamoto, Masami,Uemura, Naohiro,Yoshida, Yasushi
, (2020)
Crystallization-induced diastereomer transformation of valuable thiohydantoin derivatives was developed for the first time. Three thiohydantoins synthesized from three (R)-N-phenethylthioureas and benzoylformyl chloride were obtained as diasteromeric mixt
A photo-auxiliary approach - enabling excited state classical phototransformations with metal free visible light irradiation
Iyer, Akila,Jockusch, Steffen,Sivaguru, Jayaraman
, p. 1692 - 1695 (2017)
Most traditional photoreactions require UV light to yield the desired product. To address this issue, photoreaction of hydrazide based chromophores was evaluated with visible light using a metal free photocatalyst to afford photoproducts in high yields. This hydrazide functionality itself may be removed/modified after the photoreaction, highlighting its role as a “photo-auxiliary”. A preliminary mechanistic model based on photophysical experiments is provided to highlight the generality of the strategy.
Novel positive allosteric modulators of A2B adenosine receptor acting as bone mineralisation promoters
Barresi, Elisabetta,Giacomelli, Chiara,Marchetti, Laura,Baglini, Emma,Salerno, Silvia,Greco, Giovanni,Da Settimo, Federico,Martini, Claudia,Trincavelli, Maria Letizia,Taliani, Sabrina
, p. 286 - 294 (2020/12/22)
Small-molecules acting as positive allosteric modulators (PAMs) of the A2B adenosine receptor (A2B AR) could potentially represent a novel therapeutic strategy for pathological conditions characterised by altered bone homeostasis, including osteoporosis. We investigated a library of compounds (4-13) exhibiting different degrees of chemical similarity with three indole derivatives (1-3), which have been recently identified by us as PAMs of the A2B AR able to promote mesenchymal stem cell differentiation and bone formation. Evaluation of mineralisation activity of 4-13 in the presence and in the absence of the agonist BAY60-6583 allowed the identification of lead compounds with therapeutic potential as anti-osteoporosis agents. Further biological characterisation of one of the most performing compounds, the benzofurane derivative 9, confirmed that such a molecule behaves as PAM of the A2B AR.
Non-Bonding 1,4-Sulphur-Oxygen Interaction Governs the Reactivity of α-Ketothioesters in Triphenylphosphine-Catalyzed Cyclization with Acetylenedicarboxylates
Bankura, Abhijit,Saha, Jayanta,Maity, Rajib,Das, Indrajit
supporting information, p. 1014 - 1021 (2020/12/31)
α-Ketothioesters undergo triphenylphosphine (PPh3)-catalyzed cyclization with acetylenedicarboxylate esters smoothly, in contrast to α-ketooxoesters which require more drastic conditions with the limited substrate scope. The reaction works well
Diversification of α-ketoamides: Via transamidation reactions with alkyl and benzyl amines at room temperature
Junaid, Qazi Mohammad,Kandasamy, Jeyakumar,Popuri, Sureshbabu,Sabiah, Shahulhameed,Singh, Shweta
supporting information, p. 7134 - 7140 (2021/08/30)
A wide range of N-tosyl α-ketoamides underwent transamidation with various alkyl amines in the absence of a catalyst, base, or additive. On the other hand, transamidation in N-Boc α-ketoamides was achieved in the presence of Cs2CO3. The reactions proceede
Synthesis of N-trifluoromethyl amides from carboxylic acids
Flavell, Robert R.,Liu, Jianbo,Parker, Matthew F. L.,Toste, F. Dean,Wang, Sinan,Wilson, David M.
supporting information, p. 2245 - 2255 (2021/08/12)
Found in biomolecules, pharmaceuticals, and agrochemicals, amide-containing molecules are ubiquitous in nature, and their derivatization represents a significant methodological goal in fluorine chemistry. Trifluoromethyl amides have emerged as important functional groups frequently found in pharmaceutical compounds. To date, there is no strategy for synthesizing N-trifluoromethyl amides from abundant organic carboxylic acid derivatives, which are ideal starting materials in amide synthesis. Here, we report the synthesis of N-trifluoromethyl amides from carboxylic acid halides and esters under mild conditions via isothiocyanates in the presence of silver fluoride at room temperature. Through this strategy, isothiocyanates are desulfurized with AgF, and then the formed derivative is acylated to afford N-trifluoromethyl amides, including previously inaccessible structures. This method shows broad scope, provides a platform for rapidly generating N-trifluoromethyl amides by virtue of the diversity and availability of both reaction partners, and should find application in the modification of advanced intermediates.
Stereoselective [4+2]-Cycloaddition with Chiral Alkenylboranes
Brown, M. Kevin,Houk, K. N.,Ni, Dongshun,Witherspoon, Brittany P.,Zhang, Hong,Zhou, Chen
supporting information, p. 11432 - 11439 (2020/05/18)
A method for the stereoselective [4+2]-cycloaddition of alkenylboranes and dienes is presented. This transformation was accomplished through the introduction of a new strategy that involves the use of chiral N-protonated alkenyl oxazaborolidines as dieneophiles. The reaction leads to the formation of products that can be readily derivatized to more complex structural motifs through stereospecific transformations of the C?B bond such as oxidation and homologation. Detailed computation evaluation of the reaction has uncovered a surprising role of the counterion on stereoselectivity.
Carbene-Catalyzed Enantioselective Aromatic N-Nucleophilic Addition of Heteroarenes to Ketones
Liu, Yonggui,Luo, Guoyong,Yang, Xing,Jiang, Shichun,Xue, Wei,Chi, Yonggui Robin,Jin, Zhichao
supporting information, p. 442 - 448 (2019/11/25)
The aromatic nitrogen atoms of heteroarylaldehydes are activated by carbene catalysts to react with ketone electrophiles. Multi-functionalized cyclic N,O-acetal products are afforded in good to excellent yields and optical purities. Our reaction involves the formation of an unprecedented aza-fulvene-type acylazolium intermediate. A broad range of N-heteroaromatic aldehydes and electron-deficient ketone substrates works effectively in this transformation. Several of the chiral N,O-acetal products afforded through this protocol exhibit excellent antibacterial activities against Ralstonia solanacearum (Rs) and are valuable in the development of novel agrichemicals for plant protection.
