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1.
Chemistry ; : e202401386, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38837287

RESUMEN

Vinyl sulfones are crucial building blocks in synthetic chemistry and core structural units of pharmaceutically active molecules, thus extensive investigations have been conducted on the construction of these skeletons. In contrast to the classical synthetic approaches, the radical sulfonylation of alkynes for producing vinyl sulfones has garnered considerable interest because of its mild conditions and high efficiency. Radical sulfonation of alkynes typically begins with the sulfonyl radical attacking the alkynes, followed by further functionalization. Moreover, the association of metal-catalyst-free systems with multicomponent reactions (MCRs) offers an environmentally friendly pathway for efficiently constructing complex scaffolds from readily available partners. However, there is no comprehensive review summarizing the advancements in metal-catalyst-free multicomponent radical sulfonylation of alkynes. Hence, we provide a categorical overview based on the objects of sulfonylation of alkynes (hydrosulfonylation, carbosulfonylation, aminosulfonylation, oxysulfonylation, sulfosulfonylation, selenosulfonylation, and iodosulfonylation), along with interpretations of the reaction mechanisms.

2.
Fish Shellfish Immunol ; 144: 109320, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38122950

RESUMEN

Blood clam Tegillarca granosa is a type of economically cultivated bivalve mollusk with red blood, and it primarily relies on hemocytes in its hemolymph for immune defense. However, there are currently no reports on the isolation and identification of immune cells in T. granosa, which hinders our understanding of their immune defense. In this study, we employed single-cell transcriptome sequencing (scRNA-seq) to visualize the molecular profile of hemocytes in T. granosa. Based on differential expression of immune genes and hemoglobin genes, hemocytes can be molecularly classified into immune cells and erythrocytes. In addition, we separated immune cells using density gradient centrifugation and demonstrated their stronger phagocytic capacity compared to erythrocytes, as well as higher levels of ROS and NO. In summary, our experiments involved the isolation and functional identification of immune cells in hemolymph of T. granosa. This study will provide valuable insights into the innate immune system of red-blood mollusks and further deepen the immunological research of mollusks.


Asunto(s)
Arcidae , Bivalvos , Animales , Hemolinfa , Arcidae/genética , Bivalvos/genética
3.
Eur J Epidemiol ; 39(2): 207-218, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38198037

RESUMEN

The China Surgery and Anaesthesia Cohort (CSAC) study was launched in July 2020 and is an ongoing prospective cohort study recruiting patients aged 40-65 years who underwent elective surgeries with general anaesthesia across four medical centres in China. The general objective of the CSAC study is to improve our understanding of the complex interaction between environmental and genetic components as well as to determine their effects on a wide range of interested surgery/anaesthesia-related outcomes. To achieve this goal, we collected enriched phenotypic data, e.g., sociodemographic characteristics, lifestyle factors, perioperative neuropsychological changes, anaesthesia- and surgery-related complications, and medical conditions, at recruitment, as well as through both active (at 1, 3, 7 days and 1, 3, 6, 12 months after surgery) and passive (for more than 1 year after surgery) follow-up assessments. We also obtained omics data from blood samples. In addition, COVID-19-related information was collected from all participants since January 2023, immediately after COVID-19 restrictions were eased in China. As of July 18, 2023, 12,766 participants (mean age = 52.40 years, 57.93% were female) completed baseline data collection (response rate = 94.68%), among which approximately 70% donated blood and hair samples. The follow-up rates within 12 months after surgery were > 92%. Our initial analyses have demonstrated the incidence of and risk factors for chronic postsurgical pain (CPSP) and postoperative cognitive dysfunction (POCD) among middle-aged Chinese individuals, which may prompt further mechanistic exploration and facilitate the development of effective interventions for preventing those conditions. Additional studies, such as genome-wide association analyses for identifying the genetic determinants of CPSP and POCD, are ongoing, and their findings will be released in the future.


Asunto(s)
Anestesia , COVID-19 , Persona de Mediana Edad , Humanos , Femenino , Masculino , Estudio de Asociación del Genoma Completo , Estudios Prospectivos , Anestesia/efectos adversos , COVID-19/epidemiología , China/epidemiología
4.
Nucleic Acids Res ; 50(22): e131, 2022 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-36250636

RESUMEN

Recent advances in spatial transcriptomics (ST) have brought unprecedented opportunities to understand tissue organization and function in spatial context. However, it is still challenging to precisely dissect spatial domains with similar gene expression and histology in situ. Here, we present DeepST, an accurate and universal deep learning framework to identify spatial domains, which performs better than the existing state-of-the-art methods on benchmarking datasets of the human dorsolateral prefrontal cortex. Further testing on a breast cancer ST dataset, we showed that DeepST can dissect spatial domains in cancer tissue at a finer scale. Moreover, DeepST can achieve not only effective batch integration of ST data generated from multiple batches or different technologies, but also expandable capabilities for processing other spatial omics data. Together, our results demonstrate that DeepST has the exceptional capacity for identifying spatial domains, making it a desirable tool to gain novel insights from ST studies.


Asunto(s)
Aprendizaje Profundo , Perfilación de la Expresión Génica , Humanos , Benchmarking , Perfilación de la Expresión Génica/métodos , Transcriptoma
5.
Sensors (Basel) ; 24(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38931787

RESUMEN

Grating-type spectral imaging systems are frequently employed in scenes for high-resolution remote-sensing observations of the Earth. However, the entrance of the grating-type spectral imaging system is a slit or a pinhole. This structure relies on the push broom method, which presents a challenge in capturing spectral information of transiently changing targets. To address this issue, the IFU is used to slice the focal plane of the telescope system, thereby expanding the instantaneous field of view (IFOV) of the grating-type spectral imaging system. The aberrations introduced by the expansion of the single-slice field of view (FOV) of the IFU are corrected, and the conversion of the IFU's FOV from arcseconds to degrees is achieved. The design of a spectral imaging system based on an image-slicer IFU for remote sensing is finally completed. The system has a wavelength range of 1400 nm to 2000 nm, and a spectral resolution of better than 3 nm. Compared with the traditional grating-type spectral imaging system, its IFOV is expanded by a factor of four. And it allows for the capture of complete spectral information of transiently changing targets through a single exposure. The simulation results demonstrate that the system has good performance at each sub-slit, thereby validating the effectiveness and advantages of the proposed system for dynamic target capture in remote sensing.

6.
J Asian Nat Prod Res ; 26(4): 534-540, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37639617

RESUMEN

Based on the One Strain-Many Compounds (OSMAC) strategy, the secondary metabolites of Phomopsis lithocarpus FS508 were investigated. As a result, a new secondary metabolite, 4-methoxy-3-[4-(acetyloxy)-3-methyl-2-butenyl]benzoic acid (1) as well as eleven known compounds were isolated from the fermentation product of the strain FS508. Their structures were determined by NMR, IR, UV, and MS spectroscopic data analyses. All the isolated compounds were evaluated for cytotoxic and anti-inflammatory activities. Among them, compounds 3 and 9 displayed potent cytotoxicity against HepG-2 cell line, and compounds 2, 3 and 12 showed significant anti-inflammatory activities.


Asunto(s)
Antineoplásicos , Ascomicetos , Phomopsis , Ascomicetos/química , Línea Celular Tumoral , Antineoplásicos/química , Antiinflamatorios/farmacología , Estructura Molecular
7.
Compr Rev Food Sci Food Saf ; 23(1): e13273, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38284599

RESUMEN

Rosemary (Rosmarinus officinalis L.) is one of the most famous spice plants belonging to the Lamiaceae family as a remarkably beautiful horticultural plant and economically agricultural crop. The essential oil of rosemary has been enthusiastically welcome in the whole world for hundreds of years. Now, it is wildly prevailing as a promising functional food additive for human health. More importantly, due to its significant aroma, food, and nutritional value, rosemary also plays an essential role in the food/feed additive and food packaging industries. Modern industrial development and fundamental scientific research have extensively revealed its unique phytochemical constituents with biologically meaningful activities, which closely related to diverse human health functions. In this review, we provide a comprehensively systematic perspective on rosemary by summarizing the structures of various pharmacological and nutritional components, biologically functional activities and their molecular regulatory networks required in food developments, and the recent advances in their applications in the food industry. Finally, the temporary limitations and future research trends regarding the development of rosemary components are also discussed and prospected. Hence, the review covering the fundamental research advances and developing prospects of rosemary is a desirable demand to facilitate their better understanding, and it will also serve as a reference to provide many insights for the future promotion of the research and development of functional foods related to rosemary.


Asunto(s)
Aceites Volátiles , Rosmarinus , Humanos , Extractos Vegetales/química , Rosmarinus/química , Aditivos Alimentarios , Alimentos Funcionales , Aceites Volátiles/farmacología , Plantas
8.
J Environ Sci (China) ; 138: 189-199, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38135387

RESUMEN

Membrane distillation (MD) is a promising alternative desalination technology, but the hydrophobic membrane cannot intercept volatile organic compounds (VOCs), resulting in aggravation in the quality of permeate. In term of this, electro-Fenton (EF) was coupled with sweeping gas membrane distillation (SGMD) in a more efficient way to construct an advanced oxidation barrier at the gas-liquid interface, so that the VOCs could be trapped in this layer to guarantee the water quality of the distillate. During the so-called EF-MD process, an interfacial interception barrier containing hydroxyl radical formed on the hydrophobic membrane surface. It contributed to the high phenol rejection of 90.2% with the permeate phenol concentration lower than 1.50 mg/L. Effective interceptions can be achieved in a wide temperature range, even though the permeate flux of phenol was also intensified. The EF-MD system was robust to high salinity and could electrochemically regenerate ferrous ions, which endowed the long-term stability of the system. This novel EF-MD configuration proposed a valuable strategy to intercept VOCs in MD and will broaden the application of MD in hypersaline wastewater treatment.


Asunto(s)
Compuestos Orgánicos Volátiles , Purificación del Agua , Destilación/métodos , Membranas Artificiales , Purificación del Agua/métodos , Fenoles
9.
Small ; 19(31): e2206683, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36978241

RESUMEN

Cancer immunotherapy has become one of the current research hotspots. However, the deficiencies including restricted immunogenicity, insufficient antigen presentation, and low responsive rate limited their therapeutic applications. Own to the small size and excellent biocompatibility, carbon dots (CDs) can serve as nanovectors to improve the efficacy of cancer immunotherapy. Herein, a tumor antigen-based nanovaccines (GMal+B16F10-Ag and GMal+CT26-Ag) by the conjugation of CDs with the tumor cell-derived antigens (B16F10-Ag and CT26-Ag) is constructed. These nanovaccines can be effectively taken up by dendritic cells (DC2.4), promote DC cell maturation, cross-present the antigen to T cells, specifically target B16F10 melanoma or CT26 colon cancers, and inhibit tumor growth distinctly. This work illustrates the promise of CDs acting as versatile carriers for antigen delivery to achieve the optimal immunotherapeutic outcomes.


Asunto(s)
Vacunas contra el Cáncer , Neoplasias , Humanos , Carbono , Antígenos de Neoplasias , Neoplasias/patología , Linfocitos T , Inmunoterapia , Células Dendríticas
10.
Opt Express ; 31(26): 43198-43212, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38178419

RESUMEN

After entering the 21st century, asteroid exploration has become one of the key research directions in the field of deep space exploration. In this article, we present a navigation, imaging, and hyperspectral acquisition integrated optical system designed for asteroid exploration. Based on the pixel-level light modulation capability of the digital micromirror device (DMD), this system introduces a triple-pass total internal reflection (TIR) prism to overcome the limitation of small DMD deflection angles, achieving the co-aperture design of the high-resolution imaging branch and the hyperspectral acquisition branch. In view of the actual usage scenarios, we design a new triple-pass TIR prism and optimize it, correcting the on-axis point coma and astigmatism it introduces, and designing it to be lightweight and compact. Compared to existing optical systems for asteroid exploration, this system offers advantages such as compact structure, no moving parts, high spatial resolution, high spectral resolution, and more flexible imaging modes.

11.
Org Biomol Chem ; 21(30): 6068-6082, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37427565

RESUMEN

(4 + 2) Cycloaddition plays an important role in the synthesis of versatile carbocyclic/heterocyclic compounds with its high atom- and step-economy. Additionally, with mild conditions and indispensable functional group compatibility, the radical reaction has been recognized as a useful tool in organic chemistry. Given the enormous impact of radical-mediated (4 + 2) cycloaddition processes and their promising applications, we summarize and highlight the recent works in this attractive area. On the basis of the types of radicals that initiate different (4 + 2) cycloaddition processes, we classify them into processes involving alkenyl cations or alkenyl radicals, aryl radicals, acyl radicals, alkyl radicals, and heteroatom radicals, and this review places special emphasis on the reaction design and mechanisms, which will stimulate future developments in radical-mediated intermolecular (4 + 2) cycloaddition.

12.
Environ Sci Technol ; 57(47): 18647-18657, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36722492

RESUMEN

Ozone (O3), as an environmentally friendly oxidant, is widely used to remove emerging pollutants and ensure the safety of the water supply, whereas the restricted accessibility of O3 and limited collision frequency between pollutants and O3 will inevitably reduce the ozonation efficiency. To promote the chemical reactions between O3 and target pollutants, here we developed a novel gas-solid-liquid reaction interface dominated triphase ozonation system using a functional hydrophobic membrane with an adsorption layer as the O3 distributor and place where chemical reactions occurred. In the triphase system, the functional hydrophobic membrane simultaneously improved the interface adsorption performance of emerging pollutants and the access pathway of O3, leading to a marked enhancement of interfacial pollutant concentration and O3 levels. These synergistic qualities result in high ciprofloxacin (CIP) removal efficiency (94.39%) and fast apparent reaction rate constant (kapp, 2.75 × 10-2 min-1) versus a traditional O3 process (41.82% and 0.48 × 10-2 min-1, respectively). In addition, this triphase system was an advanced oxidation process involving radical participation and showed excellent degradation performance of multiple emerging pollutants. Our findings highlight the importance of gas-solid-liquid triphase reaction interface design and provide new insight into the efficient removal of emerging pollutants by the ozonation process.


Asunto(s)
Contaminantes Ambientales , Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Descontaminación , Contaminantes Químicos del Agua/análisis , Oxidación-Reducción
13.
Environ Sci Technol ; 57(47): 19023-19032, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37556354

RESUMEN

The industrial effluent from glyphosate production has high salinity and refractory organic contaminants. The removal of organics and the recycling of inorganic salts from this kind of water are challenging issues. In this study, electro-Fenton (EF) and membrane distillation (MD) were coupled in a single reactor utilizing a membrane-based electrode (Mem-GDE) with the ability to bidirectionally transfer vapor and oxygen and electrochemically synthesize H2O2. The operating thermal conditions for MD significantly promoted Fenton reactions and, thus, the removal of glyphosate. During operation, Fe species deposited on the Mem-GDE and enhanced its catalytic activity and adsorptive capacity, which markedly increased the apparent reaction rate constant of glyphosate by 6 times. This novel EF-MD process simultaneously removed organics and concentrated the inorganics, which is very meaningful for decreasing the costs for subsequent crystallization and achieving high-quality crystal salts. This study provides an efficient method for the treatment of organic-inorganic hybrid wastewater.


Asunto(s)
Destilación , Contaminantes Químicos del Agua , Peróxido de Hidrógeno/química , Sales (Química) , Aguas Residuales , Contaminantes Químicos del Agua/química , Oxidación-Reducción , Glifosato
14.
Cell Mol Biol (Noisy-le-grand) ; 69(12): 150-155, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38063101

RESUMEN

To investigate the effect of micro ribonucleic acid (miR)-211 on the apoptosis of nerve cells in rats with cerebral infarction through phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway. A total of 36 Sprague-Dawley (SD) rats were randomly divided into sham operation group (n=12), model group (n=12) and miR-211 mimics group (n=12). Only the common carotid artery, external carotid artery, and internal carotid artery were exposed in sham operation group, and the models of cerebral infarction were constructed via suture method in the other two groups. After modeling, the rats in sham operation group and model group were intraperitoneally injected with normal saline, while those in miR-211 mimics group were given miR-211 mimics via intraperitoneal injection. At 2 weeks after intervention, samples were collected. Neurological deficit in rats was assessed using the Zea-longa score, and Nissl staining assay was performed to observe neuronal morphology. Western blotting (WB), quantitative polymerase chain reaction (qPCR) assay and enzyme-linked immunosorbent assay (ELISA) were employed to measure the relative protein expressions of PI3K and phosphorylated AKT (p-AKT), mRNA expression of miR-211 and content of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax), respectively. Additionally, the apoptosis was detected via terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) assay. The neuronal morphology was normal in sham operation group, while it was disordered in model group, with damaged neurons. In miR-211 mimics group, the morphology of neurons was improved. The Zea-longa score was obviously higher in model group and miR-211 mimics group than that in sham operation group (P<0.05), while it was notably lower in miR-211 mimics group than that in model group (P<0.05). Compared with those in sham operation group, the relative protein expression levels of PI3K and p-AKT remarkably declined in model group and miR-211 mimics group (P<0.05), whereas they were clearly higher in miR-211 mimics group than those in model group (P<0.05). The relative expression level of miR-211 was lower in model group and miR-211 mimics group than that in sham operation group (P<0.05), while it was markedly higher in miR-211 mimics group than that in model group (P<0.05). In comparison with sham operation group, model group and miR-211 mimics group had remarkably increased content of Bax and evidently lowered content of Bcl-2 (P<0.05), whereas compared with model group, miR-211 mimics group displayed clearly reduced Bax content and notably raised Bcl-2 content (P<0.05). The apoptosis rate was distinctly higher in model group and miR-211 mimics group than that in sham operation group (P<0.05), while it was visibly lower in miR-211 mimics group than that in model group (P<0.05). MiR-211 represses the apoptosis of nerve cells in rats with cerebral infarction by up-regulating the PI3K/AKT signaling pathway, thereby protecting nerves.


Asunto(s)
Infarto Cerebral , MicroARNs , Animales , Ratas , Apoptosis/genética , Proteína X Asociada a bcl-2/metabolismo , Infarto Cerebral/genética , Infarto Cerebral/metabolismo , Modelos Animales de Enfermedad , MicroARNs/metabolismo , Neuronas/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Transducción de Señal
15.
Arch Gynecol Obstet ; 308(6): 1691-1696, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36856820

RESUMEN

PURPOSE: The ongoing coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has imposed a heavy burden on medical systems. In addition to the respiratory system, the virus also causes injuries to other organs and systems such as the gastroenteric system, kidneys, and reproductive system. Female reproductive health requires more attention in this context. METHODS: We have performed a thorough review of the relevant literature that addresses the impacts of SARS-CoV-2 infection and COVID-19 vaccination on the female reproductive system. RESULTS: Most evidence shows that SARS-CoV-2 does not infect the female reproductive system. However, the virus may indirectly influence sex hormone concentrations through inflammation associated with cytokine storms and nervous system damage. Menstrual disorders in women infected with SARS-CoV-2 may be caused by down-regulation of angiotensin-converting enzyme 2, abnormal hormone levels, medications, and stress. There is no significant difference in ovarian follicle quality and in vitro fertilization parameters between the pre- and post-COVID-19 vaccination groups. In addition, most symptoms due to side effects of vaccination could recover within a short period of time. CONCLUSION: SARS-CoV-2 infection affects female reproductive system function through multiple mechanisms. It is recommended that women of childbearing age be vaccinated with COVID-19 vaccine.


Asunto(s)
COVID-19 , Femenino , Humanos , COVID-19/prevención & control , SARS-CoV-2 , Pandemias/prevención & control , Vacunas contra la COVID-19 , Salud Reproductiva , Peptidil-Dipeptidasa A/fisiología
16.
Int J Mol Sci ; 24(6)2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36982520

RESUMEN

Candida albicans is the main causal pathogen of fungal infections in human beings. Although diverse anti-C. albicans drugs have been explored, the drug resistance and side effects of these drugs are intensifying. Thus, it is urgent to explore new anti-C. albicans compounds from natural products. In this study, we identified trichoderma acid (TA), a compound from Trichoderma spirale with a strong inhibitory effect on C. albicans. Transcriptomic and iTRAQ-based proteomic analyses of TA-treated C. albicans in combination with scanning electronic microscopy and reactive oxygen species (ROS) detection were performed to investigate the potential targets of TA. The most significant differentially expressed genes and proteins after TA treatment were verified through Western blot analysis. Our results revealed that mitochondrial membrane potential, endoplasmic reticulum, ribosomes in the mitochondria, and cell walls were disrupted in TA-treated C. albicans, leading to the accumulation of ROS. The impaired enzymatic activities of superoxide dismutase further contributed to the increase in ROS concentration. The high concentration of ROS led to DNA damage and cell skeleton destruction. The expression levels of Rho-related GTP-binding protein RhoE (RND3), asparagine synthetase (ASNS), glutathione S-transferase, and heat shock protein 70 were significantly up-regulated in response to apoptosis and toxin stimulation. These findings suggest that RND3, ASNS, and supereoxide dismutase 5 are the potential targets of TA, as further demonstrated through Western blot analysis. The combination of transcriptomic, proteomic, and cellular analyses would provide clues for the anti-C. albicans mechanism of TA and the defensive response mechanism of C. albicans. TA is thus recognized as a promising new anti-C. albicans leading compound that alleviates the hazard of C. albicans infection in human beings.


Asunto(s)
Candida albicans , Trichoderma , Humanos , Antifúngicos/farmacología , Antifúngicos/metabolismo , Trichoderma/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteómica , Pruebas de Sensibilidad Microbiana
17.
J Org Chem ; 87(21): 14487-14495, 2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36251701

RESUMEN

An efficient direct nucleophilic addition reaction of C(sp2)-H bonds to aldehydes catalyzed by a dimeric manganese has been developed. This reaction has a broad range of substrates, and high yields were also obtained with inert aliphatic aldehydes as substrates. A dimeric Mn2(CO)8Br2 was proven to be a more efficient catalyst precursor than the monomeric Mn(CO)5Br.

18.
Org Biomol Chem ; 20(47): 9272-9281, 2022 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-36383141

RESUMEN

Radical annulation has emerged as one of the most efficient and straightforward methods for synthesizing cyclic/polycyclic compounds as the core structures can be constructed through a single procedure comprising multiple bond-forming steps. Particularly, radical annulation using a radical reagent as a cyclization partner and two-carbon unit greatly expands the diversity of cyclic skeletons and the functionality of radical reagents. We herein have highlighted the representative processes reported in the past decade for radical annulation using a radical reagent as a two-carbon unit, including [2 + 2 + 2], [3 + 2], [4 + 2], and [5 + 2] modes, with an emphasis on their reaction mechanisms. These studies not only pave the way toward annulation but also provide insight into the exploration of a new reaction mode for radical chemistry.


Asunto(s)
Carbono , Indicadores y Reactivos
19.
Org Biomol Chem ; 20(24): 4900-4904, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35694954

RESUMEN

Cytospone A (1), a pyrone and isocoumarin hetero-dimer possessing an unprecedented skeleton with a polyoxygen-hetero 6/6/6/6 tetracyclic fused ring system, and three other biosynthetic precursors cytospones B-D (2-4), along with eleven known compounds were purified from Cytospora rhizophorae A761. The deduced structure of cytospone A represents the first family of natural hetero-dimers comprising pyrone and isocoumarin moieties. A plausible biogenetic pathway involving an intriguing Knoevenagel condensation/6π electrocyclization cascade sequence as the key chemical transformation is proposed.


Asunto(s)
Ascomicetos , Pironas , Ascomicetos/química , Isocumarinas , Estructura Molecular , Pironas/química
20.
Org Biomol Chem ; 20(21): 4376-4384, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35579069

RESUMEN

Three novel phomactin diterpenes neocucurbins A-C (1-3) and their derivatives, neocucurbins D-G (4-7), were isolated from the marine-derived fungus Neocucurbitaria unguis-hominis FS685. Among them, neocucurbins A-C represent the first examples of the phomactin family with an unprecedented skeleton sharing a novel polyoxygen-hetero 5/6/12 or 5/6/13 fused tricyclic ring system; whereas neocucurbins D-G feature a 5/6 fused bicyclic ring system with the opening of the macrocyclic ring, which was found in the phomactin family for the first time. Moreover, spectroscopic data analyses, single-crystal X-ray diffraction experiments, and ECD calculations were conducted to illustrate the absolute configurations of their structures. Furthermore, all seven compounds (1-7) were evaluated for their cytotoxic and antimicrobial activities.


Asunto(s)
Antineoplásicos , Ascomicetos , Diterpenos , Cristalografía por Rayos X , Diterpenos/química , Estructura Molecular
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