Marine natural products

Natural Product Reports, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A comprehensive review of 1220 new MNPs including a novel sex inducing pheromone from the diatom Seminavis robusta .

Language: Английский

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Cu-Catalyzed Amination of Base-Sensitive Aryl Bromides and the Chemoselective N- and O-Arylation of Amino Alcohols

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(27), P. 18616 - 18625

Published: June 26, 2024

We report a general and functional-group-tolerant method for the Cu-catalyzed amination of base-sensitive aryl bromides including substrates possessing acidic functional groups small five-membered heteroarenes. The results presented herein substantially expand scope C–N coupling reactions. combination L8, an anionic N1,N2-diarylbenzene-1,2-diamine ligand, along with mild base NaOTMS leads to formation stable yet reactive catalyst that resists deactivation from coordination heterocycles or charged intermediates. This system enables use low ligand loadings. Exploiting differences in nucleophile deprotonation C–O reactions catalyzed by Cu·L8 we developed chemoselectively N- O-arylate variety amino alcohol substrates. Employing NaOt-Bu as resulted exclusively when alcohols featured primary more hindered amines aniline groups. Utilizing enabled ability override steric-based selectivity these completely promoted regardless structure alcohol. invert observed chemoselectivity is distinct previously described methods require protecting group manipulations rely entirely on steric effects control reactivity. These improve using ligands introduce new chemoselective arylate alcohols.

Language: Английский

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Asymmetric Dearomatization of Nonfunctionalized 1-Naphthols via Copper-Catalyzed Enantioselective [4 + 1] Spiroannulation

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(12), P. 9244 - 9253

Published: June 3, 2024

Catalytic asymmetric dearomatization (CADA) is a powerful tool for the rapid construction of complex chiral three-dimensional cyclic molecules featuring quaternary carbon centers from readily available arenes. However, ubiquitous nonfunctionalized 1-naphthols to afford remains challenging and undeveloped. This study reports dearomative [4 + 1] spiroannulation via copper catalysis. reaction features highly chemo-, regio-, stereoselective nucleophilic addition intramolecular annulation cascade reactive π-extended copper-allenylidene, thus enabling practical synthesis range valuable spirocyclic enones bearing stereocenter with high efficiency. Furthermore, this protocol applicable phenols. Control experiments supported substitution-annulation mechanism by excluding process involving 1,3-sigmatropic shift. Preliminary biological activity studies indicated that synthesized hold significant promise as anticancer agents inducing tumor cell apoptosis.

Language: Английский

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Palladium-Catalyzed 1,2-Alkynylarylation of Vinyl Arenes with Haloalkynes and Arylboronic Acids

Organic Letters, Journal Year: 2024, Volume and Issue: 26(12), P. 2354 - 2358

Published: March 15, 2024

We herein disclose a novel palladium-catalyzed 1,2-alkynylarylation of vinyl arenes using haloalkynes and arylboronic acids as coupling partners. This reaction is characterized by broad substrate scope, controllable sequence, excellent chemo- regioselectivities. Mechanistic investigations suggest that the initiated regioselective insertion into alkynyl-Pd(II) species, silver salt crucial for this transformation, serving both Lewis acid halide scavenger. protocol provides efficient access to new carbon skeletons, which are embedded in key biologically active motifs.

Language: Английский

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Convergent Total Synthesis of Aleutianamine

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 7, 2025

Herein, we describe a convergent total synthesis of the pyrroloiminoquinone natural product aleutianamine that exemplifies novel paradigm for by hinging upon intermolecular carbon-carbon bond forming event. Specifically, coupling pyrroloquinone monoketal and siloxythiophene fragment, each prepared in seven steps from commercially available materials, allows access to entire carbon framework only eight steps. A variety intriguing skeletal rearrangements, minimal late-stage redox adjustments, carefully choreographed sequence carbon-nitrogen formations then deliver product.

Language: Английский

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A systematic and comprehensive review of the properties and synthesis of anticancer heterocyclic natural products

Current Pharmaceutical Analysis, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Language: Английский

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Synthesis of the Pentacyclic Core of Sanguinone B Enabled by Alkyne Functionalization

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: May 15, 2025

Sanguinones A and B are recently isolated pyrroloiminoquinone alkaloids possessing a rare C4 carboxylic acid. We report synthetic approach toward the full carbon nitrogen pentacyclic core of sanguinone B, with correct oxidation at C4. Highlights this include application Larock/Buchwald-Hartwig annulation cascade to access key tricyclic intermediate alkyne functionalization using Rh(I) or Cu(I) catalysis hindered benzylic ketones.

Language: Английский

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Divergent total syntheses of pyrroloiminoquinone alkaloids enabled by the development of a Larock/Buchwald–Hartwig annulation/cyclization

Chemical Science, Journal Year: 2024, Volume and Issue: 15(31), P. 12284 - 12290

Published: Jan. 1, 2024

Pyrroloiminoquinone alkaloids are a large class of natural products that display wide range biological activities. Synthetic approaches to these typically rely on common late-stage C10-oxygenated pyrroloiminoquinone intermediate, but strategies often lead lengthy synthetic sequences not amenable divergent syntheses. We devised an alternative approach aimed at the early introduction C10 nitrogen, which we hypothesized would enable diversification. This strategy hinged upon Larock/Buchwald-Hartwig annulation/cyclization quickly access core alkaloids. report development this cascade process, was facilitated by dual ligand system in addition selective functionalization key provide efficient syntheses makaluvamines A, C, and D isobatzelline B, first total synthesis makaluvamine N.

Language: Английский

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A Divergent Synthesis of Numerous Pyrroloiminoquinone Alkaloids Identifies Promising Antiprotozoal Agents

Published: Aug. 28, 2024

On the basis of a streamlined route to pyrroloiminoquinone (PIQ) core, we made 16 natural products spread across four classes biosynthetically related alkaloid products, and multiple structural analogues, all in ≤8 steps longest linear sequence (LLS). The strategy features Larock indole synthesis as key operation five-step methoxy-PIQ intermediate. Critically, this compound was readily diverged via selective methylation either (or both) imine-like or pyrrole nitrogens, which then permitted further divergence by O-demethylation o-quinone displacement methoxy group with range amine nucleophiles. Based on single, early report their potential utility against malaria parasite, assayed these com-pounds several strains Plasmodium falciparum, well two species protozoan parasite Babesia. In combination evaluations human cytotoxicity, identified compounds potent (low-nM IC50) antimalarial antibabesial activities that are much less toxic toward mammalian cells therefore promising lead for antiprotozoal drug discovery.

Language: Английский

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Manganaelectro-Catalyzed Cyclization of o-Aminoarylketones with Ammonia: An Approach to 1,2-Dihydroquinazolines

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 12, 2024

A manganaelectro-catalyzed cyclization reaction of 2-aminoarylketones with simple alcohols and ammonia under mild conditions is reported for the first time. The cooperative catalysis effectively enhances oxidation primary into aldehydes, thus enabling synthesis substituted 1,2-dihydroquinazolines in good to excellent yields. In addition, utilities this method are highlighted construction biologically active molecules that would otherwise be difficult access through a traditional method.

Language: Английский

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