A three-step mechanism involving the formation and rearrangement of an intermediate with indoline-azetidine spirocyclic core structure was shown by DFT computations to account for the electrophilic cyclization of tryptophan derivatives to hexahydropyrrolo[2,3-b]indoles. The corresponding 3a-bromo derivatives have been obtained in high yields and synthetically useful exo/endo ratios.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/ol702732j | DOI Listing |
Org Biomol Chem
January 2025
Laboratory of Asymmetric Synthesis, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, 319 Honghe Ave., Yongchuan, Chongqing, 402160, PR China.
A mild and efficient FeCl-catalyzed oxidative diselenylation of pyrrole-tethered indoles has been achieved by using RSeSeR as the source of selenium and -chloroperoxybenzoic acid (CPBA) as the oxidant (17-70% yields). In addition, this selenylation reaction system can be expanded to the functionalization of tryptophan derivatives and melatonin at the C-2 position of the indole moiety (55-58% yields).
View Article and Find Full Text PDFJ Biol Chem
January 2025
Department of Chemistry, The University of Texas at San Antonio, Texas 78249, United States. Electronic address:
MarE, a heme-dependent enzyme, catalyzes a unique 2-oxindole-forming monooxygenation reaction from tryptophan metabolites. To elucidate its enzyme-substrate interaction mode, we present the first X-ray crystal structures of MarE in complex with its prime substrate, (2S,3S)-β-methyl-L-tryptophan and cyanide at 1.89 Å resolution as well as a truncated yet catalytically active version in complex with the substrate at 2.
View Article and Find Full Text PDFmBio
January 2025
Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, University of Vienna, Vienna, Austria.
Unlabelled: In the gut, microRNAs (miRNAs) produced by intestinal epithelial cells are secreted into the lumen and can shape the composition and function of the gut microbiome. Crosstalk between gut microbes and the host plays a key role in irritable bowel syndrome (IBS) and inflammatory bowel diseases, yet little is known about how the miRNA-gut microbiome axis contributes to the pathogenesis of these conditions. Here, we investigate the ability of miR-21, a miRNA that we found decreased in fecal samples from IBS patients, to associate with and regulate gut microbiome function.
View Article and Find Full Text PDFJ Agric Food Chem
January 2025
National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals of Guizhou University, Guiyang 550025, China.
Sulfonamide derivatives have been widely used for pesticide research in recent years. Herein, 1,3,4-oxadiazole sulfonamide derivatives containing a pyrazole structure were synthesized, and their structure-activity relationship was studied. Bioactivity tests showed the remarkable efficacy of most synthesized compounds.
View Article and Find Full Text PDFMol Neurobiol
January 2025
Cellular and Molecular Neurobiology and Drug Targeting Laboratory, Department of Zoology, Indira Gandhi National Tribal University, Amarkantak-484 887, MP, India.
Depression is one of the most disabling mental disorders worldwide and characterized by symptoms including worthlessness, anhedonia, sleep, and appetite disturbances. Recently, studies have suggested that tryptophan (Trp) metabolism plays a key role in depressed mood through serotonin and kynurenine pathway involving enzyme tryptophan 5-monooxygenase (TPH) and indoleamine-2,3-dioxygenase (IDO) respectively. Moreover, during neuroinflammation, IDO is activated by proinflammatory cytokines and affects neurogenesis, cognition, disturbed hypothalamic-pituitary-adrenal (HPA) axis, and gut homeostasis by altering the gut bacteria and its metabolites like Trp derivatives.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!