Results 91 to 100 of about 36,836 (288)

Facile and Green Synthesis of Saturated Cyclic Amines

Molecules, 2017
Single-nitrogen containing saturated cyclic amines are an important part of both natural and synthetic bioactive compounds. A number of methodologies have been developed for the synthesis of aziridines, azetidines, pyrrolidines, piperidines, azepanes and
Arruje Hameed, Sadia Javed, Razia Noreen, Tayyaba Huma, Sarosh Iqbal, Huma Umbreen, Tahsin Gulzar, Tahir Farooq   +7 more
doaj   +1 more source

A Bifunctional Cytochrome P450 Enzyme Catalyzes Hydroxylation and Aryl‐Aryl Ether Formation in the Biosynthesis of Emestrin

Chemistry – A European Journal, EarlyView.
Conversion of emestrin J (5) to emestrin (1) by three P450 enzymes from the cluster (eme) in Emericella quadrilineata. EmeO acts as a bifunctional enzyme for the construction of the 15‐membered lactone ring via an aryl‐aryl ether bond formation and simultaneous hydroxylation between phenolic and nonphenolic aromatic rings, while EmeE and EmeR install ...
Yu‐Chuan Chen, Jing‐Jing Wu, Ming‐Hua Chen, Shu‐Ming Li   +3 more
wiley   +1 more source

Electrochemical Three‐Component Synthesis of Vinyl Sulfonamides via Decarboxylative Sulfonylation of Cinnamic Acids

ChemSusChem, EarlyView.
An efficient, metal‐free electrochemical three‐component reaction of cinnamic acids, SO2, and amines to access (E)‐β‐styryl sulfonamides is reported. Utilizing graphite electrodes and SO2 stock solutions, this decarboxylative protocol proceeds under mild conditions with high regio‐ and stereoselectivity.
Po‐Chung Chien, Harald Kelm, Georg Manolikakes   +2 more
wiley   +1 more source

Convergent, stereoselective syntheses of the glycosidase inhibitors broussonetines D and M [PDF]

, 2011
The first syntheses of the polyhydroxylated alkaloids (iminosugars) broussonetines D and M glycosidase inhibitors of the pyrrolidine class, have been performed in a convergent, stereocontrolled way from D-serine as the chiral starting material. A cross
Carda, Miguel, Falomir, Eva, Marco, J. Alberto, Murga, Juan, Ribés Vidal, Celia   +4 more
core   +2 more sources

Facile, Regio- and Diastereoselective Synthesis of Spiro-Pyrrolidine and Pyrrolizine Derivatives and Evaluation of Their Antiproliferative Activities

Molecules, 2014
A number of novel spiro-pyrrolidines/pyrrolizines derivatives were synthesized through [3+2]-cycloaddition of azomethine ylides with 3,5-bis[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones 2a–n.
Abdulrahman I. Almansour, Raju Suresh Kumar, Farzana Beevi, Amir Nasrolahi Shirazi, Hasnah Osman, Rusli Ismail, Tan Soo Choon, Brian Sullivan, Kellen McCaffrey, Alaa Nahhas, Keykavous Parang, Mohamed Ashraf Ali   +11 more
doaj   +1 more source

Sulfur Ylides in Skeletal‐Editing—Ring Expansion Reactions

Helvetica Chimica Acta, EarlyView.
Sulfur ylides (S‐ylides) are emergent diazo surrogates that enable skeletal editing and ring expansion with safer handling and broad functional group tolerance. This perspective covers pioneer works and highlights recent advances in the field, while outlining key challenges and future directions that may redefine the role of S‐ylides in modern ...
Arsala Kamal, Olaf Tjabben, Ana Matošević, Olga García Mancheño   +3 more
wiley   +1 more source

Studies on the C-C Bond Formation Methods Based on the Activation of Secondary Amides and the Asymmetric Total Synthesis of Cylindricine D [PDF]

, 2016
有机合成方法学和天然产物全合成是有机化学的两个重要分支，直接推动并促进有机化学及药物研发等相关学科领域的发展。 本论文包含两方面的工作，一是发展基于仲酰胺活化形成C–C键方法学的研究，二是拓展叔酰胺一瓶双烷基化构筑N-杂季碳的方法学应用到Cylindricine类生物碱的不对称合成研究。 酰胺是一类重要的有机合成和药物合成中间体，也构成了蛋白质的主要结构特征。此外，酰胺基常用作胺的保护基、C–H活化反应的活化定位基团。然而，酰胺高度稳定，羰基的反应活性非常低。因此 ...
黄应红
core  

Effect of Epigallocatechin‐3‐Gallate on Depression‐Related Cytokines in Thalassemia Patients: Molecular and Cellular Evaluation

Journal of Clinical Laboratory Analysis, EarlyView.
This study investigates the effects of Epigallocatechin‐3‐Gallate (EGCG), a potent anti‐inflammatory polyphenol isolated from Winged Marigold, on cytokine expression linked to depression in β‐thalassemia patients. EGCG demonstrated dose‐dependent suppression of key inflammatory cytokines (IL‐6, IL‐1β, TNF‐α, IFN‐γ) at both gene and protein levels ...
Mohammed N. Salman, Fouad Razzaq Al‐Burki, Hazim Ali Hussein, Laith A. Younus, Fadhil A. Nasser, Hasanain A. A. Almohseni   +5 more
wiley   +1 more source

Diastereodivergent synthesis of chiral tetrahydropyrrolodiazepinediones via a one-pot intramolecular aza-Michael/lactamization sequence [PDF]

, 2018
A modular and diastereodivergent synthesis of tetrahydro-1H-pyrrolo[1,2d]diazepine-(2,5)-diones is presented. The tetrahydropyrrolodiazepinedione scaffold is obtained via a base-mediated three-step isomerization/tandem cyclization of amino acid-coupled ...
Brown, Lauren E., Chennamadhavuni, Spandan, Panek, James S., Porco, John A.   +3 more
core   +1 more source

Radical cascades using enantioenriched 7-azabenzonorbornenes and their applications in synthesis

Beilstein Journal of Organic Chemistry, 2008
Tandem deoxygenation–neophyl-type radical rearrangement–electrophile trapping using xanthates from 7-azabenzonorbornadienes gives 3-exo-substituted 2-aza-5,6-benzonorbornenes, which in some cases undergo isomerisation to (aminomethyl)indenes.
David M. Hodgson, Leonard H. Winning
doaj   +1 more source