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1.
J Org Chem ; 89(7): 5060-5068, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38525894

RESUMEN

Radical cyclization has been demonstrated to be an efficient method to access functionalized heterocycles from easily accessible raw materials. Described herein is the development of a photocatalytic proton-coupled electron transfer (PCET) strategy for the synthesis of isoquinoline-1,3-diones using readily prepared naphthalimide (NI)-based organic photocatalysts. The process features free metal-complex photocatalysts, acids, and mild reaction conditions. This mild radical cyclization protocol has a broad substrate scope and can be effectively applied to a variety of medicinally relevant substrates. Furthermore, control experiments were conducted to elucidate the mechanism of this visible light-induced methodology.

2.
Org Biomol Chem ; 21(47): 9428-9432, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37990946

RESUMEN

Divergent aromatic ring nitrosation and nitration of aromatic amides are reported using NOBF4 as the electrophile under silver-catalyzed conditions. The reactions proceed efficiently with a wide range of compatible functionalities providing ortho-position nitrosation products, deacylation nitrosation products, and nitration products from different tertiary and secondary aromatic amides.

3.
Zhongguo Zhong Yao Za Zhi ; 48(3): 614-624, 2023 Feb.
Artículo en Zh | MEDLINE | ID: mdl-36872224

RESUMEN

Chronic heart failure(CHF) is a series of clinical syndromes in which various heart diseases progress to their end stage. Its morbidity and mortality are increasing year by year, which seriously threatens people's life and health. The diseases causing CHF are complex and varied, such as coronary heart disease, hypertension, diabetes, cardiomyopathy and so on. It is of great significance to establish animal models of CHF according to different etiologies to explore the pathogenesis of CHF and develop drugs to prevent and treat CHF induced by different diseases. Therefore, based on the classification of the etiology of CHF, this paper summarizes the animal models of CHF widely used in recent 10 years, and the application of these animal models in traditional Chinese medicine(TCM) research, in order to provide ideas and strategies for studying the pathogenesis and treatment of CHF, and provide ideas for TCM modernization research.


Asunto(s)
Cardiopatías , Insuficiencia Cardíaca , Animales , Medicina Tradicional China , Enfermedad Crónica , Modelos Animales
4.
Org Biomol Chem ; 20(2): 282-295, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34877952

RESUMEN

Nitrogen-containing heterocycles are ubiquitous fragments of numerous natural products, pharmaceuticals, designed bioactive drug candidates and agrochemicals. During the past few decades, these compounds have received considerable attention from the synthetic chemistry community, and great efforts have been focused on the development of concise and efficient methods for the synthesis of these heterocyclic skeletons. In this review, we summarize a diverse range of synthetic methods employing ß-aminovinyl esters(ketones) as key CC-N-synthons to furnish useful bioactive heterocyclic frameworks, such as quinolines, pyridines, pyrazines, pyrroles, indoles, oxazoles, imidazoles, thiazoles, isothiazoles, pyrazoles, triazoles, and azepines, thus offering new opportunities and expanding the toolbox of synthetic chemistry reactions.

5.
Org Biomol Chem ; 20(40): 7861-7885, 2022 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-36185038

RESUMEN

In recent years, isoquinoline-1,3(2H,4H)-dione compounds have attracted extensive attention from synthetic chemists, with the aim of finding simple, mild, green and efficient synthetic methods. In this review, we summarize the diverse range of synthetic methods employing acryloyl benzamides as key substrates to furnish isoquinoline-1,3-diones using different radical precursors, such as those containing carbon, sulphur, phosphorus, nitrogen, silicon and bromine. This will stimulate the interest of readers to engage in research in this field.


Asunto(s)
Bromo , Silicio , Isoquinolinas/química , Benzamidas/química , Nitrógeno , Fósforo , Azufre , Carbono
6.
Zhongguo Zhong Yao Za Zhi ; 47(7): 1705-1729, 2022 Apr.
Artículo en Zh | MEDLINE | ID: mdl-35534243

RESUMEN

The traditional Chinese medicine(TCM) contains very complex constituents. Besides the major constituents, there are a large number of unclear trace constituents with novel skeletons and potent bioactivities, which have been regarded as one of the important therapeutic substances and the great resources of innovative drugs derived from TCM. The present review highlighted that the development of the trace therapeutic substances of TCM is closely depends on the advanced technologies for their identification, isolation, structure elucidation, and bioactivity evaluation. Additionally, this paper reviewed the novel trace compounds derived from Chinese herbal medicines which have been published in Organic Letters during 2001-2021, and summarized the important licensed drugs originated from the trace therapeutic substances and the discovery and development of trace therapeutic substances of 8 kinds of Chinese herbal medicines. This review provides references for the research and development of TCM therapeutic substances and innovative drugs.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico
7.
J Org Chem ; 86(15): 10032-10042, 2021 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-34279106

RESUMEN

An effient tandem process consisting of palladium-catalyzed double-bond isomerization of long-chain olefins and subsequent intramolecular cyclization promoted by B2(OH)2 for the synthesis of aromatic oxazaheterocycles is disclosed. This strategy can also provide rapid access to pyrido[3,4-b]indoles, trans-2-olefins, and eneamides bearing various functional groups with high regio- and stereoselectivity.


Asunto(s)
Indoles , Paladio , Alquenos , Catálisis , Ciclización , Isomerismo , Estructura Molecular
8.
Chemistry ; 25(70): 16099-16105, 2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-31588599

RESUMEN

Covalent attachment of a 1,2,4-triazole iridium complex to mesoporous MCM-41 generated a heterogeneous catalyst that was found to be effective in the synthesis of 2-aryl isoindolines, quinolines, cyclic amines, and symmetrical secondary amines through a cascade borrowing hydrogen strategy. Interestingly, the supported heterogeneous iridium catalyst prepared from the 1,2,4-triazole iridium complex and mesoporous MCM-41 exhibited high catalytic activity in the preparation of 2-aryl isoindoline derivatives and symmetrical secondary amines. The catalyst system is highly recyclable for at least five times. Besides the important effect of the triazole, iridium sites grafted on siliceous supports can act as multifunctional catalytic centers and thus greatly enhance the catalytic activity of the catalysts. Furthermore, mechanistic experiments revealed that the reaction is initiated by an initial alcohol dehydrogenation and promoted by an iridium hydride intermediate. Importantly, the direct detection of a diagnostic iridium hydride signal confirmed that the synthesis of 2-aryl isoindolines occurs by a borrowing hydrogen process. This work provides an efficient example of isoindolines synthesis through a borrowing hydrogen strategy.

9.
Planta ; 248(3): 705-714, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29948125

RESUMEN

MAIN CONCLUSION: We provide evidence that Aspergillus oryzae not only acts as an endophyte in Raphanus sativus, but also works as a plant growth promoter and provides some protection against its herbivore, Plutella xylostella affecting its feeding rate, mortality and fitness parameters, thereby contributing to the pest population suppression. Seed inoculation of radish seeds with the fungus Aspergillus oryzae allowed its establishment as an endophyte promoting plant growth and negatively affecting fitness parameters of its major herbivore, diamondback moth, Plutella xylostella. Endophytic fungi may contribute to the growth of their host plants and enhance resistance to herbivores and diseases. We evaluated the effect of A. oryzae (Ahlburg) E. Cohn as an endophyte in radish (Raphanus sativus L.) on growth and development of the plants themselves and their major herbivore, the diamondback moth P. xylostella (L). A. oryzae colonization rates in leaves were significantly higher than in roots and stems, with a rate of 80% in leaves, 40% in stems and 20% in roots 1 week after seed inoculation. Colonization gradually decreased in the various plant tissues, and disappeared completely in roots, stems and leaves within 2, 5 and 7 weeks, respectively. A. oryzae did not affect seed germination; however, it promoted radish growth with endophytic plants attaining average heights of 116 mm compared to 99.6 mm in the controls at the third week post-inoculation. The P. xylostella fitness parameters, consumption, larval and pupal weights, and feeding on the endophytic plants were significantly lower than the controls, while larval mortality was significantly higher. Larvae fed on endophytic plants consumed 0.46 mg less leaf matter in the first week post seed inoculation and weighed 0.83 mg less as mature 4th instars than controls. We have demonstrated that A. oryzae can establish as an endophyte in R. sativus through seed inoculation providing some plant growth promotion and protection against its herbivore by increasing its mortality and negatively affecting its fitness parameters, suggesting that adopting seed treatments with A. oryzae may be beneficial in the commercial cultivation of radish.


Asunto(s)
Aspergillus oryzae/fisiología , Endófitos/fisiología , Mariposas Nocturnas/fisiología , Enfermedades de las Plantas/microbiología , Raphanus/microbiología , Animales , Herbivoria , Larva/fisiología , Hojas de la Planta/microbiología , Raíces de Plantas/microbiología , Raphanus/crecimiento & desarrollo
10.
Org Biomol Chem ; 16(24): 4547-4557, 2018 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-29873652

RESUMEN

A series of ferrocenyl triazole ligands have been synthesized and characterized, which proved to be effective for the Mn-catalyzed 1,6-conjugate addition/aromatization of para-quinone methides with good to high yields under mild conditions. This protocol provided an efficient and practical route to the synthetically interesting functionalized quinones, methines and their analogues.

11.
J Org Chem ; 82(16): 8455-8463, 2017 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-28731357

RESUMEN

The dual transition metal-visible light photoredox catalysis for the synthesis of quinoline derivatives by using dioxygen as an oxygen source is developed. By using visible light, the direct oxidative cyclization of aromatic enamines with alkynes or alkenes can be achieved at mild conditions with an aid of copper or palladium catalysts, and a variety of multisubstituted quinoline derivatives could be obtained in good to moderate yields under mild reaction conditions.

12.
J Org Chem ; 81(3): 1277-84, 2016 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-26760053

RESUMEN

A silver-catalyzed decarboxylative addition/aryl migration/desulfonylation of N-phenyl-N-(phenylsulfonyl)methacrylamide with primary, secondary, and tertiary carboxylic acids was described. The protocol provides an efficient approach for the synthesis of α-all-carbon quaternary stereocenters amides and isoquinolinediones. It was proposed that the radical generated from the silver-catalyzed decarboxylation was involved in the sequence reaction.

13.
J Org Chem ; 81(24): 12482-12488, 2016 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-27978757

RESUMEN

A facile copper-catalyzed radical aminoarylation of acrylamide with N-fluorobenzenesulfonimide (NFSI) is described. In the presence of copper acetate and 1,10-phenanthroline, a range of isoquinoline-1,3-diones can be constructed in moderate to good yields using NFSI as the amination reagent. Mechanistic studies demonstrated the reaction went through a sequential radical addition and cyclization pathway, which was supported by DFT calculations.

15.
J Org Chem ; 80(1): 290-5, 2015 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-25489792

RESUMEN

A novel and facile oxyazidation of alkenes under metal-free and mild conditions has been reported. A remarkable feature of the developed procedure is consecutive construction of C-O and C-N bonds in one step. The process allows quick and selective assembly of alkyl azide from readily available starting materials, where N-hydroxyphthalimide was used as an oxygen-radical precursor and TMSN3 as the N3 source. A range of aromatic alkenes bearing synthetically useful functional groups was tolerated.


Asunto(s)
Alquenos/química , Azidas/síntesis química , Ftalimidas/química , Azidas/química , Estructura Molecular , Estereoisomerismo
16.
J Org Chem ; 80(11): 5572-80, 2015 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-25970323

RESUMEN

An efficient catalytic approach for the synthesis of substituted peroxides, alcohols, and ketones through a catalyst-controlled highly selective dioxygenation of olefins has been demonstrated. The reported methods are mild and practical, can be switched by the selection of different catalytic systems, and employ peroxide as an oxidant and a reagent at room temperature.

17.
Chemistry ; 20(17): 5087-91, 2014 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-24623595

RESUMEN

A new and efficient Pd(II) -catalyzed intermolecular annulation of N-benzoylsulfonamide with allenes for the synthesis of 3,4-dihydroisoquinolin-1(2H)-ones is reported. This CH functionalization is compatible with ambient air and moisture, and it can be applied to terminal or internal allenes with different synthetically attractive functional groups. Control experiments and a kinetic isotope effect study are conducted and a plausible mechanism is proposed.

18.
Org Biomol Chem ; 12(48): 9909-13, 2014 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-25356631

RESUMEN

Arylalkynes can be converted into α-diketones with the use of a copper catalyst, and also be transformed into vinyl acetates under metal-free conditions, both in the presence of PhI(OAc)2 as an oxidant at room temperature. A series of substituted α-diketones were prepared in moderate to good yields. A variety of vinyl halides could be regio- and stereo-selectively synthesized under mild conditions, and I, Br and Cl could be all easily embedded into the alkynes.


Asunto(s)
Alquinos/química , Cetonas/síntesis química , Oxígeno/química , Compuestos de Vinilo/síntesis química , Cristalografía por Rayos X , Cetonas/química , Modelos Moleculares , Estructura Molecular , Compuestos de Vinilo/química
19.
Org Lett ; 26(18): 3982-3986, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38690829

RESUMEN

Described herein is the development of a visible-light-induced photoredox 1,6-enyne reductive cyclization via selective reduction of a triple bond instead of an activated double bond. The selective 1,6-enyne radical cyclization/carbon═carbon double bond cleavage provided a straightforward route to structurally valuable α,ß-unsaturated γ-lactams. TEMPO-trap experiments, control experiments, and DFT calculations have offered evidence supporting the possible catalytic cycle.

20.
Fitoterapia ; 176: 105981, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38685513

RESUMEN

An investigation of EtOAc extract from the roots of Paeonia lactiflora yielded three new 30-noroleanane triterpenoids paeonenoides L-N (1-3) and one new oleanane triterpenoid paeonenoide O (4) together with 7 known compounds (5-11). Extensive spectrographic experiments were applied to identify the structures of 1-4, and their absolute configurations were unambiguously determined by theoretical calculations of ECD spectra, as well as the single-crystal X-ray diffraction analysis. Compounds 8, 9 and 10 were isolated from the Paeonia genus for the first time. Moreover, compounds 8, 9 and 11 showed inhibitory activities against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages with the IC50 values of 72. 17 ± 4.74, 30.02 ± 2.03 and 28.34 ± 1.85 µM, respectively.


Asunto(s)
Óxido Nítrico , Ácido Oleanólico , Paeonia , Fitoquímicos , Raíces de Plantas , Raíces de Plantas/química , Paeonia/química , Ratones , Animales , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacología , Ácido Oleanólico/aislamiento & purificación , Ácido Oleanólico/química , Células RAW 264.7 , Estructura Molecular , Óxido Nítrico/metabolismo , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Triterpenos/farmacología , Triterpenos/aislamiento & purificación , Triterpenos/química , China , Macrófagos/efectos de los fármacos
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