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1.
Org Lett ; 26(37): 7908-7913, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39254672

RESUMEN

A highly efficient, atom-economical α-allylation reaction of NH2-unprotected amino acid esters and alkynes is achieved by chiral aldehyde/palladium combined catalysis. A diverse range of α,α-disubstituted nonproteinogenic α-amino acid esters are produced in 31-92% yields and 84-97% ee values. The allylation products are utilized for the synthesis of drug molecule BMS561392 and other chiral molecules possessing complex structures. Mechanistic investigations reveal that this reaction proceeds via a chiral aldehyde-/palladium-mediated triple cascade catalytic cycle.

2.
Biol Reprod ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39303127

RESUMEN

Recurrent miscarriage (RM) is a chronic and heterogeneous pregnancy disorder lacking effective treatment. Alterations at the maternal-fetal interface are commonly observed in RM, with the loss of certain cell subpopulations believed to be a key cause. Through single-cell sequencing of RM patients and healthy donors, we aim to identify aberrancy of cellular features in RM tissues, providing new insights into the research. Natural killer (NK) cells, the most abundant immune cells in the decidua, are traditionally classified into dNK1, dNK2, and dNK3. In this study, we identified a new subset, dNK1/2, absent in RM tissues. This subset was named because it expresses biomarkers of both dNK1 and dNK2. With further analysis, we discovered that dNK1/2 cells play roles in immunoregulation and cytokine secretion. On the villous side of the interface, a notable decrease of extravillous trophoblast (EVT) cells was identified in RM tissues. We clustered EVTs into EVT1 (absent in RM) and EVT2 (retained in RM). Pseudotime analysis revealed distinct differentiation paths, identifying CCNB1, HMGB1, and NPM1 as EVT1 biomarkers. Additionally, we found that EVT1 is involved in the regulation of cell death, while EVT2 exhibited more angiogenic activity. Cell communication analysis revealed that interaction between EVT1 and dNK1/2 mediates chemotaxis and endothelial cell regulation, crucial for spiral artery remodeling. The loss of this interaction may impair decidualization, which is associated with RM. In summary, we propose that the loss of dNK1/2 and EVT1 cells is a significant pathological feature of RM.

3.
Front Endocrinol (Lausanne) ; 15: 1429514, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39247918

RESUMEN

Background: Evidence suggests a connection between DNA methylation (DNAm) aging and reproductive aging. However, the causal relationship between DNAm and age at menopause remains uncertain. Methods: Employing established DNAm epigenetic clocks, such as DNAm Hannum age acceleration (Hannum), Intrinsic epigenetic age acceleration (IEAA), DNAm-estimated granulocyte proportions (Gran), DNAm GrimAge acceleration (GrimAgeAccel), DNAm PhenoAge acceleration (PhenoAgeAccel), and DNAm-estimated plasminogen activator inhibitor-1 levels (DNAmPAIadjAge), a bidirectional Mendelian randomization (MR) study was carried out to explore the potential causality between DNAm and menopausal age. The primary analytical method used was the inverse variance weighted (IVW) estimation model, supplemented by various other estimation techniques. Results: DNAm aging acceleration or deceleration, as indicated by Hannum, IEAA, Gran, GrimAgeAccel, PhenoAgeAccel, and DNAmPAIadjAge, did not exhibit a statistically significant causal effect on menopausal age according to forward MR analysis. However, there was a suggestive positive causal association between age at menopause and Gran (Beta = 0.0010; 95% confidence interval (CI): 0.0004, 0.0020) in reverse MR analysis. Conclusion: The observed increase in granulocyte DNAm levels in relation to menopausal age could potentially serve as a valuable indicator for evaluating the physiological status at the onset of menopause.


Asunto(s)
Metilación de ADN , Epigénesis Genética , Análisis de la Aleatorización Mendeliana , Menopausia , Humanos , Femenino , Menopausia/genética , Persona de Mediana Edad , Envejecimiento/genética , Adulto , Factores de Edad
4.
Chem Sci ; 15(32): 12983-12988, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39148795

RESUMEN

Even though catalytic asymmetric bifunctionalization of allenes has been extensively studied, almost all of the reported examples have been achieved in a two-component manner. In this study, we report a highly efficient asymmetric bifunctionalization of allenes with iodohydrocarbons and NH2-unprotected amino acid esters. The adopted chiral aldehyde/palladium combined catalytic system precisely governs the chemoselectivity, regioselectivity, and stereoselectivity of this three-component reaction. A wide range of substituted aryl iodides, allenes and amino acid esters can well participate in this reaction and deliver structurally diverse α,α-disubstituted α-amino acid esters with excellent experimental outcomes. One of the resulting products is utilized for the total synthesis of the molecule (S,R)-VPC01091.

5.
Front Endocrinol (Lausanne) ; 15: 1422752, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39211449

RESUMEN

Diabetes and its complications significantly affect individuals' quality of life. The etiology of diabetes mellitus and its associated complications is complex and not yet fully understood. There is an increasing emphasis on investigating the effects of endocrine disruptors on diabetes, as these substances can impact cellular processes, energy production, and utilization, ultimately leading to disturbances in energy homeostasis. Mitochondria play a crucial role in cellular energy generation, and any impairment in these organelles can increase susceptibility to diabetes. This review examines the most recent epidemiological and pathogenic evidence concerning the link between endocrine disruptors and diabetes, including its complications. The analysis suggests that endocrine disruptor-induced mitochondrial dysfunction-characterized by disruptions in the mitochondrial electron transport chain, dysregulation of calcium ions (Ca2+), overproduction of reactive oxygen species (ROS), and initiation of signaling pathways related to mitochondrial apoptosis-may be key mechanisms connecting endocrine disruptors to the development of diabetes and its complications.


Asunto(s)
Diabetes Mellitus , Disruptores Endocrinos , Mitocondrias , Humanos , Disruptores Endocrinos/efectos adversos , Disruptores Endocrinos/toxicidad , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Diabetes Mellitus/inducido químicamente , Diabetes Mellitus/metabolismo , Animales , Complicaciones de la Diabetes/metabolismo , Complicaciones de la Diabetes/inducido químicamente , Especies Reactivas de Oxígeno/metabolismo , Exposición a Riesgos Ambientales/efectos adversos
6.
Sci Rep ; 14(1): 20229, 2024 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-39215059

RESUMEN

To develop a simple scoring system based on baseline inflammatory and nutritional markers to predict the long-term prognosis of patients with nasopharyngeal carcinoma (NPC). Conducted a retrospective analysis of clinical data from 1024 newly diagnosed non-metastatic NPC patients. A total of 15 pre-treatment inflammatory and nutritional markers were collected as candidate variables. Receiver operating characteristic (ROC) curves were used to determine the optimal cutoff points for each parameter. Survival analysis was performed using Kaplan-Meier method and Cox regression analysis. Besides, the Inflammation Nutrition Risk Score (INRS) was calculated for each patient by assigning each independent prognostic factor a score of 1. Multivariate Cox regression analysis showed that serum albumin (ALB), systemic immune-inflammation index, and monocyte count (M) were independent prognostic factors for OS (P < 0.05). Survival analysis showed that higher INRS was associated with a worsened prognosis. Patients in the high-risk group had shorter OS than in the low-risk group. In the training group, the 3-, 5-, and 8-years OS rates for the low-risk group versus high-risk group were 92.5% versus 87.8%, 87.4% versus 75.1%, and 84.6% versus 62.2%, respectively (P < 0.05). In the validation group, the 3-, 5-, and 8-years OS rates for the low-risk group vs. high-risk group were 95.0% versus 86.4%, 92.1% versus 82.2%, and 89.5% versus 74.3%, respectively (P < 0.05). Further subgroup analysis showed a significant difference in the OS between the high-risk group and low-risk group in patients with locally advanced disease (P < 0.05). The ROC curve demonstrated that INRS had a similar predictive value for long-term survival in NPC patients compared to TNM staging and serum EBV-DNA levels. Pretreatment ALB, M, and SIRI are independent prognostic factors for long-term survival in patients with NPC. INRS constructed based on these three factors can serve as a long-term prognostic indicator for NPC.


Asunto(s)
Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Masculino , Femenino , Carcinoma Nasofaríngeo/mortalidad , Carcinoma Nasofaríngeo/patología , Persona de Mediana Edad , Neoplasias Nasofaríngeas/mortalidad , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/sangre , Pronóstico , Adulto , Estudios Retrospectivos , Inflamación , Anciano , Curva ROC , Estimación de Kaplan-Meier , Estado Nutricional , Albúmina Sérica/análisis
7.
Chem Sci ; 15(26): 10232-10236, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38966351

RESUMEN

Despite the long-standing exploration of the catalytic asymmetric Tsuji-Trost allylation reaction since the mid-20th century, most reported instances have adhered to a two-component approach. Here, we present a remarkably efficient three-component asymmetric allylation reaction enabled by the collaborative action of chiral aldehyde and palladium. A diverse array of NH2-unprotected amino acid esters, aryl or alkenyl iodides, and allyl alcohol esters exhibit robust participation in this reaction, resulting in the synthesis of structurally diverse non-proteinogenic α-amino acid esters with favorable experimental outcomes. Mechanistic investigations reveal the dominance of the allylation/Heck coupling cascade in reactions involving electron-rich aryl iodides, while the Heck coupling/allylation cascade emerges as the dominant pathway in reactions involving electron-deficient aryl iodides. This chiral aldehyde/palladium combining catalytic system precisely governs the chemoselectivity of C-allylation and N-allylation, the regioselectivity of linear and branched allylation, and the enantioselectivity of C-allylation products.

8.
Adv Sci (Weinh) ; 11(28): e2402429, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38751149

RESUMEN

Axially chiral thioethers and sulfoxides emerge as two pivotal classes of ligands and organocatalysts, which have remarkable features in the stereoinduction of various asymmetric transformations. However, the lack of easy methods to access such molecules with diverse structures has hampered their broader utilization. Herein, an oxidative kinetic resolution for sulfides using a chiral bifunctional squaramide as the catalyst with cumene hydroperoxide as the terminal oxidant is established. This asymmetric approach provides a variety of axially chiral thioethers as well as sulfoxides bearing both axial and central chirality, with excellent diastereo- and enantioselectivities. This catalytic system also successfully extends to the kinetic resolution of benzothiophene-based sulfides. Preliminary mechanism investigation indicates that the multiple hydrogen bonding interactions between the bifunctional squaramide catalyst and substrates play a crucial role in determining the enantioselectivity and reactivity.

9.
Front Pharmacol ; 15: 1338902, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38434706

RESUMEN

Introduction: Linezolid is an oxazolidinone antibiotic that is active against drug-resistant Gram-positive bacteria and multidrug-resistant Mycobacterium tuberculosis. Real-world studies on the safety of linezolid in large populations are lacking. This study aimed to determine the adverse events associated with linezolid in real-world settings by analyzing data from the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). Methods: We retrospectively extracted reports on adverse drug events (ADEs) from the FAERS database from the first quarter of 2004 to that of 2023. By using disproportionality analysis including reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian Confidence Propagation Neural Network (BCPNN), along with the multi-item gamma Poisson shrinker (MGPS), we evaluated whether there was a significant association between linezolid and ADE. The time to onset of ADE was further analyzed in the general population and within each age, weight, reporting population, and weight subgroups. Results: A total of 11,176 reports of linezolid as the "primary suspected" drug and 263 significant adverse events of linezolid were identified, including some common adverse events such as thrombocytopenia (n = 1,139, ROR 21.98), anaemia (n = 704, ROR 7.39), and unexpected signals that were not listed on the drug label such as rhabdomyolysis (n = 90, ROR 4.33), and electrocardiogram QT prolonged (n = 73, ROR 4.07). Linezolid-induced adverse reactions involved 27 System Organ Class (SOC). Gender differences existed in ADE signals related to linezolid. The median onset time of all ADEs was 6 days, and most ADEs (n = 3,778) occurred within the first month of linezolid use but some may continue to occur even after a year of treatment (n = 46). Conclusion: This study reports the time to onset of adverse effects in detail at the levels of SOC and specific preferred term (PT). The results of our study provide valuable insights for optimizing the use of linezolid and reducing potential side effects, expected to facilitate the safe use of linezolid in clinical settings.

10.
Zygote ; 32(2): 130-138, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38248872

RESUMEN

Spermatogenesis is a developmental process driven by interactions between germ cells and Sertoli cells. This process depends on appropriate gene expression, which might be regulated by transcription factors. This study focused on Rreb1, a zinc finger transcription factor, and explored its function and molecular mechanisms in spermatogenesis in a mouse model. Our results showed that RREB1 was predominantly expressed in the Sertoli cells of the testis. The decreased expression of RREB1 following injection of siRNA caused impaired Sertoli cell development, which was characterized using a defective blood-testis barrier structure and decreased expression of Sertoli cell functional maturity markers; its essential trigger might be SMAD3 destabilization. The decreased expression of RREB1 in mature Sertoli cells influenced the cell structure and function, which resulted in abnormal spermatogenesis, manifested as oligoasthenoteratozoospermia, and we believe RREB1 plays this role by regulating the transcription of Fshr and Wt1. RREB1 has been reported to activate Fshr transcription, and we demonstrated that the knockdown of Rreb1 caused a reduction in follicle-stimulating hormone receptor (FSHR) in the testis, which could be the cause of the increased sperm malformation. Furthermore, we confirmed that RREB1 directly activates Wt1 promoter activity, and RREB1 downregulation induced the decreased expression of Wt1 and its downstream polarity-associated genes Par6b and E-cadherin, which caused increased germ-cell death and reduced sperm number and motility. In conclusion, RREB1 is a key transcription factor essential for Sertoli cell development and function and is required for normal spermatogenesis.


Asunto(s)
Células de Sertoli , Espermatogénesis , Factores de Transcripción , Animales , Masculino , Ratones , Barrera Hematotesticular/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Ratones Endogámicos C57BL , Receptores de HFE/genética , Receptores de HFE/metabolismo , Células de Sertoli/metabolismo , Proteína smad3/metabolismo , Proteína smad3/genética , Espermatogénesis/genética , Testículo/metabolismo , Testículo/citología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas WT1/genética , Proteínas WT1/metabolismo
11.
Cancer Med ; 13(1): e6891, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38169158

RESUMEN

BACKGROUND: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on postoperative recovery of non-small cell lung cancer (NSCLC) is need to be understood, thereby informing the optimal timing of surgical decision-making during the COVID-19 pandemic for NSCLC patients. This study reports the postoperative outcomes of surgical NSCLC patients with preoperative SARS-CoV-2 infection. METHOD: This single-center retrospective cohort study included 241 NSCLC patients who underwent lobectomy or sub-lobectomy between December 1, 2022 and February 14, 2023. Surgical outcomes of patients with preoperative SARS-CoV-2 infection (stratified by the time from diagnosis of SARS-CoV-2 infection to surgery) were compared with those without preoperative SARS-CoV-2 infection. The primary outcomes were total postoperative complications and postoperative pulmonary complications (PPCs), the secondary outcomes included operation time, total postoperative drainage and time, length of hospital stay (LOS), 30-day and 90-day postoperative symptoms. RESULTS: This study included 153 (63.5%) patients with preoperative SARS-CoV-2 infection and 88 (36.5%) patients without previous SARS-CoV-2 infection. In patients with a preoperative SARS-CoV-2 diagnosis, the incidence of total postoperative complications (OR, 3.00; 95% CI, 1.12-8.01; p = 0.028) and PPCs (OR, 4.20; 95% CI, 1.11-15.91; p = 0.035) both increased in patients infected having surgery within 2 weeks compared with non-infection before surgery. However, patients who underwent lung resection more than 2 weeks after SARS-CoV-2 diagnosis had a similar risk of postoperative complications and surgical outcomes with those non-infection before surgery. CONCLUSION: This is the first study to provide evidence regarding the optimum timing of lung resection surgery and assessing early outcomes after surgery in NSCLC patients with SARS-CoV-2 infection. Our study documents that the SARS-CoV-2 infection did not complicate surgical procedures for lung cancer, and suggest that lung surgery should be postponed at least 2 weeks after SARS-CoV-2 infection for NSCLC patients.


Asunto(s)
COVID-19 , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Neumonectomía , Complicaciones Posoperatorias , SARS-CoV-2 , Humanos , COVID-19/complicaciones , COVID-19/epidemiología , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Carcinoma de Pulmón de Células no Pequeñas/virología , Masculino , Femenino , Neoplasias Pulmonares/cirugía , Neoplasias Pulmonares/virología , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Neumonectomía/efectos adversos , Neumonectomía/métodos , Complicaciones Posoperatorias/epidemiología , Tiempo de Internación , Factores de Tiempo , Tiempo de Tratamiento
12.
Angew Chem Int Ed Engl ; 63(12): e202319089, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38277401

RESUMEN

Purely organic materials exhibiting room temperature phosphorescence (RTP) are promising candidates for oxygen sensors and information encryption owing to their cost-effective and environmentally friendly nature. Herein, we report a bimolecular RTP system where DTBU acts as the guest and TBBU serves as the host. In contrast to previously reported results, we find that both pure DTBU and TBBU do not exhibit RTP in the solid state even under N2 atmosphere. A DTBU/TBBU system with a low doping ratio (0.1 mol %) exhibits persistent yellowish-green afterglow with a lifetime of 340 ms and is highly sensitive to oxygen. A DTBU/TBBU system with a higher doping ratio (10 mol %) maintains a phosphorescence lifetime of 179 ms under air. Applications of DTBU/TBBU at varied doping ratios in both oxygen sensing and information encryption are demonstrated. We propose that the T1 state of TBBU acts as an energy transfer intermediate between Tn and T1 of DTBU, ultimately leading to the generation of persistent RTP. Overall, this work demonstrates the critical importance of material purity in the design of RTP systems, and how an understanding of host-guest doping enables their photophysical properties to be precisely tuned.

13.
Org Lett ; 26(1): 153-159, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38133484

RESUMEN

Aiming at the reported chiral synthons leading to manzacidins A and D, here we report a highly efficient catalytic asymmetric α-allenylic alkylation reaction of NH2-unprotected amino acid esters that is promoted by combined chiral aldehyde/palladium catalysis. Fifty examples of unnatural α,α-disubstituted amino acid esters are reported with good-to-excellent yields and stereoselectivities. Based on this methodology, a key intermediate leading to manzacidin C and its other three stereoisomers is prepared accordingly.

14.
Aging Cell ; 22(12): e14028, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38015106

RESUMEN

Human aging is invariably accompanied by a decline in renal function, a process potentially exacerbated by uremic toxins originating from gut microbes. Based on a registered household Chinese Guangxi longevity cohort (n = 151), we conducted comprehensive profiling of the gut microbiota and serum metabolome of individuals from 22 to 111 years of age and validated the findings in two independent East Asian aging cohorts (Japan aging cohort n = 330, Yunnan aging cohort n = 80), identifying unique age-dependent differences in the microbiota and serum metabolome. We discovered that the influence of the gut microbiota on serum metabolites intensifies with advancing age. Furthermore, mediation analyses unveiled putative causal relationships between the gut microbiota (Escherichia coli, Odoribacter splanchnicus, and Desulfovibrio piger) and serum metabolite markers related to impaired renal function (p-cresol, N-phenylacetylglutamine, 2-oxindole, and 4-aminohippuric acid) and aging. The fecal microbiota transplantation experiment demonstrated that the feces of elderly individuals could influence markers related to impaired renal function in the serum. Our findings reveal novel links between age-dependent alterations in the gut microbiota and serum metabolite markers of impaired renal function, providing novel insights into the effects of microbiota-metabolite interplay on renal function and healthy aging.


Asunto(s)
Microbioma Gastrointestinal , Humanos , Anciano , China , Metaboloma , Envejecimiento , Biomarcadores , Riñón
15.
Front Endocrinol (Lausanne) ; 14: 1217613, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37745721

RESUMEN

Background: Tumor multifocality is frequently observed in papillary thyroid carcinoma (PTC). However, the maximum tumor diameter (MTD), currently utilized in various staging schemes, might not accurately indicate the level of aggressiveness exhibited by multifocal tumors. We aimed to investigate the relationship between total tumor diameter (TTD) and clinicopathological features of papillary thyroid carcinoma. Methods: Retrospective data analysis was done on 1936 individuals who underwent complete thyroidectomy for PTC. Patients were classified into subgroups according to unilateral multifocality, central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM). The relationships of clinicopathological features among these groups were analyzed. Results: Unilateral multifocality was observed in 117 patients. The clinicopathological features of the unilateral multifocal PTC were similar to the unifocal PTC with approximate TTD. The unilateral multifocality played no independent role in CLNM and LLNM. Moreover, the efficiency of TTD in predicting CLNM and LLNM was significantly higher than that of MTD. Conclusion: In the case of unilateral multifocal PTC, TTD is a more accurate indicator of the biological characteristics of the tumor than MTD.


Asunto(s)
Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo/cirugía , Metástasis Linfática , Puntaje de Propensión , Estudios Retrospectivos , Neoplasias de la Tiroides/cirugía
16.
Angew Chem Int Ed Engl ; 62(38): e202305175, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37527975

RESUMEN

Cyclopropane skeletons play a prominent role in the development of organic synthesis and pharmaceutical chemistry. Herein, we report the design and synthesis of a stable, multifunctional (diborylmethyl)iodide reagent (CHI(Bpin)2 ) for the photoinduced cyclopropanation of alkenes, providing an array of 1,2-substituted cyclopropylboronates in good yields. This α-haloboronic ester can be readily synthesized on a multigram scale from commercially available starting materials. Furthermore, the protocol displays high chemo- and diastereoselectivity, excellent functional-group tolerance, and allows for late-stage borylcyclopropanation of complex molecules. Mechanistic studies reveal that the borylcyclopropanation proceeds through a radical addition/polar cyclization pathway mediated by the photocatalyst fac-Ir(ppy)3 and visible light.

17.
Org Lett ; 25(31): 5790-5794, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37523673

RESUMEN

A chiral aldehyde/palladium catalysis-enabled asymmetric α-allylation of NH2-unprotected amino acid esters with 1,3-disubstituted allyl acetates is described in this work. With the utilization of different chiral phosphine ligands, both the anti- and syn-selective allylation reactions are achieved enantioselectively. A series of α,α-disubstituted amino acid esters bearing two adjacent chiral centers are produced in moderate-to-excellent yields, diastereoselectivities, and enantioselectivities.

18.
Chem Sci ; 14(21): 5665-5671, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37265737

RESUMEN

The direct catalytic α-hydrocarbylation of readily available amino acids with halohydrocarbons is one of the most straightforward methods leading to α,α-disubstituted non-proteinogenic α-amino acid compounds. However, all the reported methodologies depend on N-protected amino acids as starting materials. Herein, we report on three highly efficient aldehyde-catalyzed direct α-hydrocarbylations of N-unprotected amino acid esters with aryl-, allyl-, and benzyl halides. By promoting a simple chiral BINOL-aldehyde catalyst or combining catalysts of a chiral aldehyde and Lewis acid ZnCl2, the asymmetric α-arylation, α-allylation, and α-benzylation of amino acid esters with the corresponding halohydrocarbons proceed smoothly, producing α,α-disubstituted α-amino acids in moderate-to-high yields and good-to-excellent enantioselectivities. The asymmetric α-arylation reaction can be applied in the formal synthesis of the clinical candidate compound (+)-AG-041R. Based on the results given by control experiments, three reaction models are proposed to illustrate the stereoselective-control outcomes.

19.
Angew Chem Int Ed Engl ; 62(32): e202301186, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37189285

RESUMEN

Artificial lighting currently consumes approximately one-fifth of global electricity production. Organic emitters with white persistent RTP have potential for applications in energy-efficient lighting technologies, due to their ability to harvest both singlet and triplet excitons. Compared to heavy metal phosphorescent materials, they have significant advantages in cost, processability, and reduced toxicity. Phosphorescence efficiency can be improved by introducing heteroatoms, heavy atoms, or by incorporating luminophores within a rigid matrix. White-light emission can be achieved by tuning the ratio of fluorescence to phosphorescence intensity or by pure phosphorescence with a broad emission spectrum. This review summarizes recent advances in the design of purely organic RTP materials with white-light emission, describing single-component and host-guest systems. White phosphorescent carbon dots and representative applications of white-light RTP materials are also introduced.

20.
Transl Lung Cancer Res ; 12(3): 446-459, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37057109

RESUMEN

Background: With an increasing amount of small nodules being detected, segmentectomy has recently received a great deal of attention. We have previously reported the feasibility and safety of uniportal segmentectomy. This study aims to further compare the perioperative and oncological outcomes of uniportal and three-port thoracoscopic segmentectomy in lung cancer patients. Methods: Patients undergoing thoracoscopic segmentectomy for lung cancer from January 2014 to March 2021 were enrolled. Clinical data were collected from the Western China Lung Cancer Database, a prospectively maintained database at the Department of Thoracic Surgery, West China Hospital. Propensity score matching (PSM) was used to reduce the heterogeneity in baseline characteristics. Perioperative outcomes, 1-, 3-, and 5-year overall survival (OS), and progression-free survival (PFS) were compared. Results: Of the 10,063 lung cancer patients who underwent thoracoscopic lung resection, 2,630 patients receiving segmentectomy were selected (uniportal: 400; three-port: 2,230). After matching, similar results were found between the 2 groups (uniportal: 400; three-port: 1,200) regarding the number of lymph nodes harvested, the length of postoperative hospital stays, chest tube drainage volume, and postoperative complication rate. The mean follow-up duration was 27 months. Uniportal regimen showed similar 1- (100% vs. 99.9%, P=0.36), 3- (100% vs. 90.4%, P=0.20), 5-year OS (97.7% vs. 99.4%, P=0.78), as well as PFS, with the three-port regimen. Conclusions: Uniportal video-assisted thoracoscopic segmentectomy is proven to be safe and feasible, and the perioperative outcomes and oncological results were similar between the uniportal and three-port regimens.

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