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1.
Org Biomol Chem ; 22(3): 585-589, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38131265

RESUMEN

Allylic amination is a powerful tool for constructing N-allylic amines widely found in bioactive molecules. Generally, allylic alcohols and unsaturated hydrocarbons have been considered for allylic amination reactions to minimize waste production. Herein, we present an iridium-catalysed method for reductive allylic amination of α,ß-unsaturated aldehydes with amines to afford N-allylic amines under air conditions. This protocol is demonstrated to provide products from many substrates (41 examples) in moderate-to-excellent yields. This synthetic methodology is also highlighted by the synthesis of drug molecules, optically pure products, as well as scale-up experiments.

2.
Clin Lab ; 70(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38213209

RESUMEN

BACKGROUND: Rab1A not only regulates eukaryotic secretion, autophagy and intracellular traffic, but also extensively participates in the development of cancer. Thus, we collected data to investigate the clinical value of Rab1A in cancers. METHODS: English web database was searched for appropriate studies. The role of Rab1A in cancer patients was evaluated by combining hazard ratios and odds ratios. RESULTS: There were 15 studies in 14 articles, including 1,791 cancer patients. The results showed that upregulated Rab1A led to poor prognosis in cancer patients (pooled HR = 2.545, 95% CI = 1.924 - 3.367, p < 0.001). Notably, a high level of Rab1A was associated with a poorer prognosis than patients with a low level of Rab1A in digestive system cancer (pooled HR = 2.484, 95% CI = 1.796 - 3.437, p < 0.001). In order to explore the possible carcinogenic mechanism, we further analyzed and confirmed that high expression of Rab1A was associated with worse histologic grade, deeper tumor invasion, higher TNM stage, positive LN metastasis, positive neural invasion, positive vascular invasion, and larger tumor size (p < 0.05). CONCLUSIONS: Rab1A overexpression was associated with poor prognosis and adverse clinicopathological parameters in cancer patients and had the potential to be a target for future cancer therapy.


Asunto(s)
Neoplasias del Sistema Digestivo , Humanos , Pronóstico , Modelos de Riesgos Proporcionales , Biomarcadores de Tumor/metabolismo
3.
Molecules ; 29(11)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38893441

RESUMEN

N-aryl-substituted pyrrolidines are important moieties widely found in bioactive substances and drugs. Herein, we present a practical reductive amination of diketones with anilines for the synthesis of N-aryl-substituted pyrrolidines in good to excellent yields. In this process, the N-aryl-substituted pyrrolidines were furnished via successive reductive amination of diketones via iridium-catalyzed transfer hydrogenation. The scale-up performance, water as a solvent, simple operation, as well as derivation of drug molecules showcased the potential application in organic synthesis.

4.
J Environ Manage ; 339: 117822, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37054589

RESUMEN

Triadimefon is ubiquitous in various environmental media. Although toxicity of triadimefon to individual of aquatic organisms has been confirmed, its effect on organisms at population level remain poorly understood. In this study the long-term effect of triadimefon on individual and population of Daphnia magna were studied using multi-generational experiments and matrix model. Development and reproduction of three generations of F1 and F2 were significantly inhibited with the triadimefon concentration of 0.1 mg/L (p < 0.01). Toxicity of triadimefon to the offspring was stronger than to the parent (p < 0.05). When triadimefon concentration was higher than 0.1 mg/L, both population number and intrinsic rate of increase showed a decreasing trend with the increasing exposure concentration. Age structure of the population also tended to decline. Toxicity threshold derived on population-level was between mortality-based LC50 and reproduction-based NOEC of Daphnia magna, and also between acute toxicity and chronic toxicity derived from species sensitivity distribution (SSD). The risk of population level derived from risk quotient was low for most areas, and the results derived from probability risk showed that the expected loss of intrinsic rate of increase of population was 0.0039 without considering other factors. Compared to the individual-level, the ecological risks at the population level were closer to the actual situation of the ecosystem response to the chemical pollution.


Asunto(s)
Fungicidas Industriales , Contaminantes Químicos del Agua , Animales , Daphnia/fisiología , Fungicidas Industriales/toxicidad , Fungicidas Industriales/química , Ecosistema , Contaminantes Químicos del Agua/toxicidad , Reproducción
5.
Org Biomol Chem ; 20(13): 2621-2625, 2022 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-35302576

RESUMEN

An iridium complex-catalyzed reductive etherification of α,ß-unsaturated ketones and aldehydes with primary alcohols is presented, affording allyl ethers in excellent yields. Deuterated and control experiments showed that this etherification transformation proceeded through a cascade transfer hydrogenation and alcohol condensation process. Moreover, the utility of this protocol is evidenced by the gram-scale performance.


Asunto(s)
Alcoholes , Iridio , Aldehídos , Catálisis , Hidrogenación , Cetonas , Estereoisomerismo
6.
Org Biomol Chem ; 20(32): 6394-6399, 2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-35866589

RESUMEN

Cationic iridium (Ir) complexes were found to catalyze the transfer hydrogenation of oximes to access N-alkoxy amines and hydroxylamines, and the reaction was accelerated by trifluoroacetic acid. The practical application of this protocol was demonstrated by a gram-scale transformation and two-step synthesis of the fungicide furmecyclox (BAS 389F) in overall yields of 92 and 85%, respectively. An asymmetric protocol using chiral Ir complexes to afford chiral N-alkoxy amines was demonstrated, but the low yields/ee obtained indicated that further development was required.


Asunto(s)
Aminas , Iridio , Alcoholes , Catálisis , Hidrogenación , Hidroxilaminas , Oximas , Estereoisomerismo
7.
Org Biomol Chem ; 20(26): 5239-5244, 2022 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-35723258

RESUMEN

A photoinduced radical cascade cyclization of acetylenic acid esters with oxime esters is described, providing cyanalkylated coumarins in superior yields under mild conditions. Radical capture and luminescence quenching experiments showed that this transformation was accomplished via a radical addition/5-exo spirocyclization/1,2-ester migration process.


Asunto(s)
Cumarinas , Oximas , Alquinos , Ciclización , Ésteres , Ácidos Grasos Insaturados
8.
World J Surg Oncol ; 20(1): 351, 2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36309698

RESUMEN

BACKGROUND: It has been previously reported that CD155 is often over-expressed in a variety of cancer types. In fact, it is known to be involved in cancer development, and its role in cancer has been widely established. However, clinical and mechanistic studies involving CD155 yielded conflicting results. Thus, the present study aimed to evaluate overall prognostic value of CD155 in cancer patients, using a comprehensive analysis. METHODS: Online databases were searched, data was collected, and clinical value of CD155 was evaluated by combining hazard ratios (HRs) or odds ratios (ORs). RESULTS: The present study involved meta-analysis of 26 previous studies that involved 4325 cancer patients. These studies were obtained from 25 research articles. The results of the study revealed that increased CD155 expression was significantly associated with reduced OS in patients with cancer as compared to low CD155 expression (pooled HR = 1.772, 95% CI = 1.441-2.178, P < 0.001). Furthermore, subgroup analysis demonstrated that the level of CD155 expression was significantly associated with OS in patients with digestive system cancer (pooled HR = 1.570, 95% CI = 1.120-2.201, P = 0.009), hepatobiliary pancreatic cancer (pooled HR = 1.677, 95% CI = 1.037-2.712, P = 0.035), digestive tract cancer (pooled HR = 1.512, 95% CI = 1.016-2.250, P = 0.042), breast cancer (pooled HR = 2.137, 95% CI = 1.448-3.154, P < 0.001), lung cancer (pooled HR = 1.706, 95% CI = 1.193-2.440, P = 0.003), head and neck cancer (pooled HR = 1.470, 95% CI = 1.160-1.862, P = 0.001). Additionally, a significant correlation was observed between enhanced CD155 expression and advanced tumor stage (pooled OR = 1.697, 95% CI = 1.217-2.366, P = 0.002), LN metastasis (pooled OR = 1.953, 95% CI = 1.253-3.046, P = 0.003), and distant metastasis (pooled OR = 2.253, 95% CI = 1.235-4.110, P = 0.008). CONCLUSION: Altogether, the results of the present study revealed that CD155 acted as an independent marker of prognosis in cancer patients, and it could provide a new and strong direction for cancer treatment.


Asunto(s)
Neoplasias de la Mama , Neoplasias del Sistema Digestivo , Humanos , Femenino , Pronóstico , Biomarcadores de Tumor/metabolismo , Modelos de Riesgos Proporcionales
9.
World J Surg Oncol ; 19(1): 266, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34479600

RESUMEN

BACKGROUND: MicroRNA-140 (miR-140) is one of the most widely investigated miRNAs in cell carcinogenesis and cancer development. Despite present proposals of employing miR-140 as a candidate biomarker for cancer prognosis, its effectiveness in predicting patient survival and clinicopathological outcome is still under debate. METHODS: A systematic search for English literature using online databases was performed with pre-established criteria. Odds ratios (ORs) or hazard ratios (HRs) with 95% confidence intervals (CIs) were collected to delineate the correlation between miR-140 levels and cancer patient prognosis. RESULTS: For this meta-analysis, we selected 12 papers for analysis, involving 1386 participants. Based on our analysis, high levels of miR-140 were strongly correlated with enhanced patient overall survival (OS) (HR = 0.728, 95% CI = 0.601-0.882, P = 0.001). In addition, we also observed that elevated miR-140 levels significantly led to better OS in patients with cancers in different parts of the body like digestive system (HR = 0.675, 95% CI = 0.538-0.848, P = 0.001), digestive tract (HR = 0.709, 95% CI = 0.565-0.889, P = 0.003), and head and neck (HR = 0.603, 95% CI = 0.456-0.797, P < 0.001). Additionally, we verified that the low miR-140 levels was related to advanced TNM stage (OR = 0.420, 95% CI = 0.299-0.590, P < 0.001), worse histologic grade (OR = 0.410, 95% CI = 0.261-0.643, P < 0.001), and positive lymph node metastasis status (OR = 0.341, 95% CI = 0.144-0.807, P = 0.014). CONCLUSIONS: Taken together, our results suggest that elevated miR-140 levels can be employed as a favorable biomarker for cancer patient prognosis. This information can greatly benefit in the formation of an individualized therapeutic plan for the treatment of cancer patients.


Asunto(s)
MicroARNs , Neoplasias , Biomarcadores de Tumor/genética , Humanos , Metástasis Linfática , MicroARNs/genética , Neoplasias/genética , Pronóstico , Modelos de Riesgos Proporcionales
10.
J Org Chem ; 85(8): 5590-5597, 2020 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32223198

RESUMEN

Here we describe a photoredox-catalyzed oxy-/aminofluoroalkylative cyclization of alkenes for coupling available Rf-I reagents to generate fluoroalkylated 2,3-dihydrobenzofuran and indolin derivatives with good to excellent yields under mild conditions. A wide range of functional groups are tolerated. The mechanistic investigation of radical trapping and cyclic voltammetry experiments proposed that a radical/SET (single electron transfer) pathway proceeded in this reaction.

11.
Org Biomol Chem ; 18(25): 4709-4716, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32525196

RESUMEN

Isoxazoline compounds are used as important intermediates for the synthesis of organic molecules, which are widely used in the chemical and life science industries. Oxime-participating cyclization has emerged as an efficient strategy for the construction of isoxazolines. This review is devoted to highlighting the main achievements (since 2010) in the development of methodologies for the synthesis of isoxazolines. According to the reaction mechanism, the oxime-participating synthesis of isoxazolines can be mainly classified into four reaction types: iminoxyl radical-initiated intramolecular cyclization, intermolecular radical addition-initiated cyclization, intramolecular nucleophilic cyclization, and [3 + 2] cycloaddition. Meanwhile, miscellaneous examples are also illustrated, such as [2 + 2 + 1] cycloaddition. Representative reactions will be discussed for each of the highlighted synthetic strategies. In addition, the enantioselective synthesis of isoxazolines is also illustrated in this review.

12.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(9): 942-947, 2020 Sep.
Artículo en Zh | MEDLINE | ID: mdl-32933623

RESUMEN

OBJECTIVE: To investigate the clinical features and outcome of neonatal acute respiratory distress syndrome (ARDS) in southwest Hubei, China. METHODS: According to the Montreux definition of neonatal ARDS, a retrospective clinical epidemiological investigation was performed on the medical data of neonates with ARDS who were admitted to Department of Neonatology/Pediatrics in 17 level 2 or level 3 hospitals in southwest Hubei from January to December, 2017. RESULTS: A total of 7 150 neonates were admitted to the 17 hospitals in southwest Hubei during 2017 and 66 (0.92%) were diagnosed with ARDS. Among the 66 neonates with ARDS, 23 (35%) had mild ARDS, 28 (42%) had moderate ARDS, and 15 (23%) had severe ARDS. The main primary diseases for neonatal ARDS were perinatal asphyxia in 23 neonates (35%), pneumonia in 18 neonates (27%), sepsis in 12 neonates (18%), and meconium aspiration syndrome in 10 neonates (15%). Among the 66 neonates with ARDS, 10 neonates (15%) were born to the mothers with an age of ≥35 years, 30 neonates (45%) suffered from intrauterine distress, 32 neonates (49%) had a 1-minute Apgar score of 0 to 7 points, 24 neonates (36%) had abnormal fetal heart monitoring results, and 21 neonates (32%) experienced meconium staining of amniotic fluid. Intraventricular hemorrhage was the most common comorbidity (12 neonates), followed by neonatal shock (9 neonates) and patent ductus arteriosus (8 neonates). All 66 neonates with ARDS were treated with mechanical ventilation in addition to the treatment for primary diseases. Among the 66 neonates with ARDS, 10 died, with a mortality rate of 15% (10/66), and 56 neonates were improved or cured, with a survival rate of 85% (56/66). CONCLUSIONS: Neonatal ARDS in southwest Hubei is mostly mild or moderate. Perinatal asphyxia and infection may be the main causes of neonatal ARDS in this area. Intraventricular hemorrhage is the most common comorbidity. Neonates with ARDS tend to have a high survival rate after multimodality treatment.


Asunto(s)
Síndrome de Dificultad Respiratoria del Recién Nacido , China , Femenino , Humanos , Recién Nacido , Síndrome de Aspiración de Meconio , Embarazo , Estudios Retrospectivos
13.
Angew Chem Int Ed Engl ; 58(48): 17148-17152, 2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-31489752

RESUMEN

Described here is a new and viable approach to achieve Pd catalysis for aerobic oxidation systems (AOSs) by circumventing problems associated with both the oxidation and the catalysis through an all-in-one strategy, employing a robust metal-organic framework (MOF). The rational assembly of a PdII catalyst, phenanthroline ligand, and CuII species (electron-transfer mediator) into a MOF facilitates the fast regeneration of the PdII active species, through an enhanced electron transfer from in situ generated Pd0 to CuII , and then CuI to O2 , trapped in the framework, thus leading to a 10 times higher turnover number than that of the homogeneous counterpart for Pd-catalyzed desulfitative oxidative coupling reactions. Moreover, the MOF catalyst can be reused five times without losing activity. This work provides the first exploration of using a MOF as a promising platform for the development of Pd catalysis for AOSs with high efficiency, low catalyst loading, and reusability.

14.
Inorg Chem ; 57(3): 1203-1212, 2018 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-29309133

RESUMEN

The development of well-defined multimetallic porous metal-organic frameworks (MOFs) will add a new dimension to the application of MOF catalysis. From this perspective, the understanding and tailoring of the catalytic metal sites in MOFs are key fundamental challenges that could reveal the intrinsic potential of these materials. In this work, a series of porphyrin-salen chiral MOFs (ps-CMOFs 2-7) have been synthesized through postsynthetic metalation (PSMet) of the parent ps-CMOF via single-crystal to single-crystal transformation. Crystal structures of these ps-CMOF analogues revealed the same topological structure but varied metal entities compared to those of the parent framework. Note that the PSMet process involves three methods involving cation exchange at the nodes, cation exchange at the metalated porphyrin, and cation addition at the free porphyrin, which has been systematically investigated using single-crystal X-ray diffraction and other physicochemical methods. The N2 adsorption tests, thermogravimetric analysis, and powder X-ray diffraction of 2-7 showed curves or patterns similar to those of 1, indicating the maintenance of the crystallinity, porosity, and thermal stability of the framework during the PSMet process. In addition, 2-7 showed distinctly improved adsorption capacities and isosteric heats of adsorption (Qst) for CO2 compared to those of their parent counterpart. Lastly, as a representative example of the ps-CMOF catalytic platform, 5 proved to be an efficient recyclable heterogeneous catalyst for the asymmetric addition reaction of CO2 with epoxides under mild conditions. Furthermore, because of the constrained chiral environment within ps-CMOF, the enantioselectivity of this reaction appears to be dependent on substrate size.

15.
Biochem Biophys Res Commun ; 494(3-4): 511-517, 2017 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-29106957

RESUMEN

Deleted in Breast Cancer 1 (DBC1) is a regulatory protein involved in cell metabolism and cancer progression. Nevertheless, the expression and prognostic values of DBC1 in hepatocellular carcinoma (HCC) are still not well understood. The following study investigated the clinical significance and biological function of DBC1 in HCC. Briefly, overexpression of DBC1 at transcriptional and translational levels in human HCC tissues compared to adjacent normal tissues was observed using quantitative real-time polymerase chain reaction (qRT-PCR), western blot (WB) and immunohistochemistry (IHC) approach. Furthermore, upregulated DBC1 was significantly correlated with tumor size (p = 0.005), N stage (p = 0.016), M stage (p = 0.011), tumor differentiation (p < 0.001), and American Joint Committee on Cancer (AJCC) stage (p = 0.001). Moreover, Kaplan-Meier survival analysis revealed that DBC1 was an independent prognosis predictor for disease-free survival (DFS) (p < 0.001) and overall survival (OS) (p < 0.001). In addition, by using Cell Counting Kit-8 (CCK8) assays and colony formation assays, we found that the knockdown of DBC1 significantly suppressed the proliferation of HCC cells in vitro. To conclude, these findings demonstrated that DBC1 was essential in tumorigenesis and proliferation. Moreover, it was identified as a potential therapeutic target for HCC.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidad , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidad , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , China/epidemiología , Supervivencia sin Enfermedad , Humanos , Neoplasias Hepáticas/patología , Persona de Mediana Edad , Terapia Molecular Dirigida/métodos , Prevalencia , Pronóstico , Factores de Riesgo , Estadística como Asunto , Tasa de Supervivencia , Regulación hacia Arriba
16.
J Org Chem ; 82(20): 10912-10919, 2017 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-28879764

RESUMEN

An efficient and practical protocol for the synthesis of (E)-allylethers from readily available olefins with alcohols or phenols was developed. This aerobic oxidative allylic C-H oxygenation protocol features mild conditions, broad substrate scope, and high atom and step economy, making it a valuable and convenient synthetic method. Notably, molecular oxygen is the sole oxidant in this novel transformation.

17.
Curr Microbiol ; 74(5): 641-649, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28299440

RESUMEN

Agaricus bisporus (J. E. Lange) Imbach, well known as the common cultivated mushroom or white button mushroom, is widely cultivated all over the world. We used iTRAQ-MS/MS (i.e., isobaric tags for relative and absolute quantification-coupled two-dimensional liquid chromatography-tandem mass spectrometry) to identify protein expression changes that occur during the post-harvest maturation of Agaricus bisporus fruitbodies at 0, 6, 12, and 48 h after harvest. A total of 5878 unique peptides, representing 1063 proteins, were identified. Quantitative data were obtained from 1012 out of the 1063 proteins. A total of 102, 106, and 160 differentially expressed proteins (>twofolds differences) were identified from samples collected at 6, 12, and 48 h compared to sample from 0 h post harvest, accounting for 10.1, 10.5, and 15.8% of the total proteins identified, respectively. All identified proteins including the differentially expressed proteins among different post-harvest stages were subjected to bioinformatic analysis. Furthermore, seven representative proteins either up or down-regulated at different post-harvest stages were analyzed by real-time PCR. Three out of the seven proteins, the mismatched base pair and cruciform DNA recognition protein, hydrophobin-B and protein transporter, exhibited similar expression patterns as their corresponding proteins. The 260 differentially expressed proteins identified from our study laid a foundation for future studies aiming to understand the post-harvest maturation process of A. bisporus and eventually, might help in the development of breeding program to identify strains with extended shelf life.


Asunto(s)
Agaricus/metabolismo , Proteínas Fúngicas/metabolismo , Proteoma , Proteómica , Agaricus/genética , Cromatografía Liquida , Cuerpos Fructíferos de los Hongos , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Fenotipo , Proteómica/métodos , Espectrometría de Masas en Tándem
18.
Angew Chem Int Ed Engl ; 56(5): 1289-1293, 2017 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-27966816

RESUMEN

Demonstrated herein is a highly effective 3 starting materials-4 component reaction (3SM-4CR) strategy for the synthesis of pyrimidine carboxamides from amidines, styrene, and N,N-dimethylformamide (DMF) by a palladium-catalyzed oxidative process. This transformation represents the first example of employing DMF as a dual synthon, a one-carbon-atom synthon and amide synthon, and was proven by isotope-labeling experiments. Additionally, the combination of C-H bond functionalization and cross-dehydrogenative coupling processes affords four chemical bond formations. This sequential 3SM-4CR strategy features inexpensive, readily available starting materials, green oxidants, as well as atom and step economy. It leads to the preparation of pyrimidine carboxamides and has potential applications in the pharmaceutical industry.

19.
J Org Chem ; 81(3): 1304-9, 2016 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-26757241

RESUMEN

An efficient procedure for the preparation of allylic trifluoromethanesulfones with high regioselectivity from aromatic allylic alcohols/esters and NaSO2CF3 under transition-metal-free conditions is described. A wide range of functional groups were tolerated. This is the first example to realize different types of allylic alcohols, including primary, secondary, and tertiary allylic alcohols, all of which transferred to the corresponding products efficiently in good to excellent yields with readily available and inexpensive NaSO2CF3. The synthetic utility of the method was demonstrated by performing the reaction at gram scale.

20.
J Org Chem ; 81(13): 5538-46, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27275869

RESUMEN

Various polysubstituted pyrimidines are smoothly formed via a base-promoted intermolecular oxidation C-N bond formation of allylic C(sp(3))-H and vinylic C(sp(2))-H of allyllic compounds with amidines using O2 as the sole oxidant. This protocol features protecting group free nitrogen sources, good functional group tolerance, high atom economy, and environmental advantages.

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