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1.
J Am Chem Soc ; 146(19): 12883-12888, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709642

RESUMEN

Polyamides represent one class of materials that is important in modern society. Because of the numerous potential applications of polyamides in various fields, there is a high demand for new polyamide structures, which necessitates the development of new polymerization methods. Herein, we report a novel and efficient palladium-catalyzed hydroaminocarbonylative polymerization of dienes and diamines for the synthesis of cycloaliphatic polyamides. The method employs readily available starting materials, proceeds in an atom-economic manner, and creates a series of new functional polyamides in high yields and high molecular weights. In contrast with the traditional polyamides based on adipic acid, the cycloaliphatic polyamides have superior thermal resistance, higher glass-transition temperature, and better solubility in common organic solvents, thus probably featuring the merits of high-performance and good processability.

2.
Mediators Inflamm ; 2024: 4465592, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38707705

RESUMEN

Objective: This study aims to evaluate the impact and predictive value of the preoperative NPRI on short-term complications and long-term prognosis in patients undergoing laparoscopic radical surgery for colorectal cCancer (CRC). Methods: A total of 302 eligible CRC patients were included, assessing five inflammation-and nutrition-related markers and various clinical features for their predictive impact on postoperative outcomes. Emphasis was on the novel indicator NPRI to elucidate its prognostic and predictive value for perioperative risks. Results: Multivariate logistic regression analysis identified a history of abdominal surgery, prolonged surgical duration, CEA levels ≥5 ng/mL, and NPRI ≥ 3.94 × 10-2 as independent risk factors for postoperative complications in CRC patients. The Clavien--Dindo complication grading system highlighted the close association between preoperative NPRI and both common and severe complications. Multivariate analysis also identified a history of abdominal surgery, tumor diameter ≥5 cm, poorly differentiated or undifferentiated tumors, and NPRI ≥ 2.87 × 10-2 as independent risk factors for shortened overall survival (OS). Additionally, a history of abdominal surgery, tumor maximum diameter ≥5 cm, tumor differentiation as poor/undifferentiated, NPRI ≥ 2.87 × 10-2, and TNM Stage III were determined as independent risk factors for shortened disease-free survival (DFS). Survival curve results showed significantly higher 5-year OS and DFS in the low NPRI group compared to the high NPRI group. The incorporation of NPRI into nomograms for OS and DFS, validated through calibration and decision curve analyses, attested to the excellent accuracy and practicality of these models. Conclusion: Preoperative NPRI independently predicts short-term complications and long-term prognosis in patients undergoing laparoscopic colorectal cancer surgery, enhancing predictive accuracy when incorporated into nomograms for patient survival.


Asunto(s)
Neoplasias Colorrectales , Laparoscopía , Neutrófilos , Complicaciones Posoperatorias , Prealbúmina , Humanos , Neoplasias Colorrectales/cirugía , Masculino , Femenino , Persona de Mediana Edad , Anciano , Pronóstico , Prealbúmina/metabolismo , Factores de Riesgo , Supervivencia sin Enfermedad , Adulto , Análisis Multivariante , Modelos Logísticos
3.
Angew Chem Int Ed Engl ; 63(26): e202406226, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38618886

RESUMEN

In contrast to the kinetically favored outward isomerization-hydrocarbonylation of alkenes, the disfavored inward isomerization-hydrocarbonylation of alkenes remains an important challenge. Herein, we have developed a novel and effective palladium-catalyzed inward isomerization-hydroaminocarbonylation of unactivated alkenes and aniline hydrochlorides for the formation of synthetically valuable α-aryl carboxylic amides in high yields and high site-selectivities. The high efficiency of the reaction is attributed to a relay catalysis strategy, in which the Markovnikov-favored [PdH]-PtBu3 catalyst is responsible for inward isomerization, while the [PdH]-Ruphos catalyst is responsible for hydroaminocarbonylation of the resulting conjugated aryl alkenes. The reaction exhibits highly functional group tolerance and provides a new method for formal carbonylation of remote C(sp3)-H bond.

4.
Macromol Rapid Commun ; 44(20): e2300281, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37543181

RESUMEN

Intelligent actuating materials have drawn enormous attention because of their potential applications in soft robots, smart sensors, bionics, etc. Aiming to integrate light, thermal, and humidity stimuli deformations and self-healing function into a single polymer, a smart actuating polyurethane material CPPU-50 is designed and successfully synthesized through co-polymerization of azobenzene-containing Azo-C12 , polyethylene glycol 200 (PEG200), and 4,4'-diphenylmethane diisocyanate (MDI) at a ratio of 1:1:2. The obtained polyurethane CPPU-50 exhibits good photoinduced bending, thermal responsive shape memory effect, humidity triggered deflections and self-healing properties. Furthermore, an actuator combining light and thermal stimuli is created and the self-healing CPPU-50 film can withstand the object of 1800 times without tearing. This work can pave a way for further development of long-lived multi-stimuli-responsive actuating devices and intelligent materials.


Asunto(s)
Poliuretanos , Materiales Inteligentes , Humedad , Biónica , Polietilenglicoles , Polímeros
5.
Zhonghua Nan Ke Xue ; 28(10): 886-890, 2022 Oct.
Artículo en Zh | MEDLINE | ID: mdl-37838954

RESUMEN

OBJECTIVE: To study the effect of the bladder wall neourethra (BWN) technique on early urinary continence after laparoscopic radical prostatectomy (LRP). METHODS: We prospectively selected 40 cases of LRP performed in our hospital from August 2020 to August 2021 and randomly divided them into a BWN group (n = 20) and a control group (n = 20). We recorded the urinary continence rate of the two groups of patients at 7, 30, 90 and 180 days, and measured the maximum urethral pressure (MUP), functional urethral length (FUL) and functional urethral area (UFA) and observed the shape of the neourethra closure by MRI at 1 month after catheter removal. RESULTS: The urinary continence rates were significantly higher in the BWN than in the control group at 7 days (90.0% vs 25.0%, P < 0.001), 30 days (95.0% vs 35.0%, P < 0.001), 90 days (100% vs 60.0%, P < 0.05) and 180 days (100% vs 90.0%, P > 0.05) after catheter removal. No statistically significant difference was observed in MUP between the two groups (P > 0.05). FUL and FUA were remarkably higher in the BWN than in the control group (P < 0.01). MRI showed tight closure of the neourethra in the BWN group in the urine storage period. CONCLUSION: The BWN technique can significantly prolong FUL and improve early urinary continence after LRP.


Asunto(s)
Laparoscopía , Incontinencia Urinaria , Masculino , Humanos , Vejiga Urinaria/cirugía , Incontinencia Urinaria/prevención & control , Incontinencia Urinaria/cirugía , Prostatectomía/efectos adversos , Prostatectomía/métodos , Uretra/cirugía , Laparoscopía/métodos , Recuperación de la Función
6.
J Am Chem Soc ; 143(19): 7298-7305, 2021 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-33970621

RESUMEN

Hydroaminocarbonylation of alkenes is one of the most promising yet challenging methods for the synthesis of amides. Herein, we reported the development of a novel and effective Pd-catalyzed Markovnikov hydroaminocarbonylation of 1,1-disubstituted or 1,1,2-trisubstituted alkenes with aniline hydrochloride salts to afford amides bearing an α quaternary carbon. The reaction makes use of readily available starting materials, tolerates a wide range of functional groups, and provides a facile and straightforward approach to a diverse array of amides bearing an α quaternary carbon. Mechanistic investigations suggested that the reaction proceeded through a palladium hydride pathway. The hydropalladation and CO insertion are reversible, and the aminolysis is probably the rate-limiting step.

7.
J Am Chem Soc ; 143(1): 85-91, 2021 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-33373216

RESUMEN

A palladium-catalyzed asymmetric Markovnikov hydroaminocarbonylation of alkenes with anilines has been developed for the atom-economical synthesis of 2-substituted propanamides bearing an α-stereocenter. A novel phosphoramidite ligand L16 was discovered which exhibited very high reactivity and selectivity in the reaction. This asymmetric Markovnikov hydroaminocarbonylation employs readily available starting materials and tolerates a wide range of functional groups, thus providing a facile and straightforward method for the regio- and enantioselective synthesis of 2-substituted propanamides under ambient conditions. Mechanistic studies revealed that the reaction proceeds through a palladium hydride pathway.

8.
Angew Chem Int Ed Engl ; 60(43): 23117-23122, 2021 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-34240535

RESUMEN

Asymmetric hydroxycarbonylation is one of the most fundamental yet challenging methods for the synthesis of carboxylic acids. Herein, we reported the development of a palladium-catalyzed highly enantioselective Markovnikov hydroxycarbonylation of vinyl arenes with CO and water. A monodentate phosphoramidite ligand L6 plays vital role in the reaction. The reaction tolerates a range of functional groups, and provides a facile and atom-economical approach to an array of 2-arylpropanoic acids including several commonly used non-steroidal anti-inflammatory drugs. The catalytic system has also enabled an asymmetric Markovnikov hydroalkoxycarbonylation of vinyl arenes with alcohols to afford 2-arylpropanates. Mechanistic investigations suggested that the hydropalladation is irreversible and is the regio- and enantiodetermining step, while hydrolysis/alcoholysis is probably the rate-limiting step.

9.
J Org Chem ; 85(12): 7939-7951, 2020 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-32441101

RESUMEN

An iodoxybenzoic acid-mediated selected oxidative cyclization of N-hydroxyalkyl enamines was developed. Through this strategy, a variety of 2,3-disubstituted pyrroles and pyridines were produced in good selectivity involving oxidation of alcohol, followed by condensation of aldehyde and α-C of enamines. Furthermore, this metal-free method has several advantages, including the use of environmentally friendly reagents, broad substrate scope, mild reaction conditions, and high efficiency.

10.
Angew Chem Int Ed Engl ; 59(29): 12199-12205, 2020 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-32239787

RESUMEN

Reported herein is the development of the first enantioselective monodentate ligand assisted Pd-catalyzed domino Heck carbonylation reaction with CO. The highly enantioselective domino Heck carbonylation of N-aryl acrylamides and various nucleophiles, including arylboronic acids, anilines, and alcohols, in the presence of CO was achieved. A novel monodentate phosphoramidite ligand, Xida-Phos, has been developed for this reaction and it displays excellent reactivity and enantioselectivity. The reaction employs readily available starting materials, tolerates a wide range of functional groups, and provides straightforward access to a diverse array of enantioenriched oxindoles having ß-carbonyl-substituted all-carbon quaternary stereocenters, thus providing a facile and complementary method for the asymmetric synthesis of bioactive hexahydropyrroloindole and its dimeric alkaloids.

11.
Org Biomol Chem ; 16(23): 4333-4337, 2018 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-29808898

RESUMEN

A modular 2H-azirine synthesis from ketoxime acetates via Cs2CO3-mediated cyclization has been developed. The reaction utilizes easily available starting materials and provides a general synthetic route to 2,3-diaryl-2H-azirines in good to excellent yields under mild conditions, which is complementary to the conventional approaches for the synthesis of 2H-azirines. A gram-scale reaction was performed to demonstrate the scale-up applicability of this synthetic method. Importantly, 2H-azirines can be efficiently converted to various azaheterocycles.

12.
Org Biomol Chem ; 15(5): 1091-1095, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28090616

RESUMEN

A new Cu-catalyzed efficient protocol is described for the transformation of oximes to the corresponding carbonate derivatives. Diisopropyl azodicarboxylate acted as a selective new precursor for the synthesis of oxime carbonates in high yields. The O-H bond cleavage and O-C bond formation occur in the presence of a copper catalyst providing a synthetically useful process, which tolerates a wide range of functional groups.

13.
J Org Chem ; 81(10): 4226-34, 2016 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-27101475

RESUMEN

A simple and efficient protocol for the fluoroacetylation of indoles is reported. The reaction uses fluorinated acetic acids as the fluoroacetylation reagents to synthesize diverse fluoromethyl indol-3-yl ketones in good yields under catalyst- and additive-free conditions. In addition, the only byproduct is water in this transformation. The synthetic utility of this reaction was also demonstrated by the concise synthesis of α-(trifluoromethyl)(indol-3-yl)methanol and indole-3-carboxylic acid.

14.
Org Biomol Chem ; 14(30): 7136-49, 2016 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-27345290

RESUMEN

Pyrroles are important synthetic targets as a result of their occurrence in numerous biologically active molecules, their important roles in diverse living processes, and their utility as versatile intermediates. As a consequence, numerous efforts focused on the development of concise and efficient methods for the construction of pyrroles. Compared with other transition metals, the group 1B metals (Cu, Ag and Au) are probably more versatile and widely used for the synthesis of pyrroles in organic chemistry. Considering the importance of both topics in organic synthesis, here we summarize recent achievements in the synthesis of pyrroles catalyzed by monometallic systems which belong to the group 1B metals (Cu, Ag and Au).


Asunto(s)
Cobre/química , Oro/química , Compuestos Organometálicos/química , Pirroles/síntesis química , Plata/química , Catálisis , Técnicas de Química Sintética/métodos , Estructura Molecular , Relación Estructura-Actividad
15.
J Org Chem ; 80(2): 1258-63, 2015 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-25560397

RESUMEN

A Pd(II)-catalyzed C-H monocarbonylation of N-alkylanilines for the synthesis of o-aminobenzoates has been developed. Various aliphatic alcohols and phenol were tolerated in the reaction to afford the corresponding o-aminobenzoates in good yields under mild balloon pressure of CO.

16.
Chemistry ; 20(7): 1839-42, 2014 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-24453126

RESUMEN

An efficient copper-promoted oxidative coupling of enamides with alkynes has been developed for the synthesis of substituted pyrroles. The reaction proceeded through C-H and N-H bond functionalization of enamides under mild conditions.


Asunto(s)
Alquinos/química , Amidas/química , Cobre/química , Pirroles/síntesis química , Catálisis , Acoplamiento Oxidativo , Pirroles/química
17.
J Org Chem ; 79(9): 4196-200, 2014 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-24720706

RESUMEN

A novel palladium-catalyzed oxidative double carbonylation of o-iodoanilines for the synthesis of isatoic anhydrides has been developed. The reaction employs readily available o-iodoanilines as the starting materials and proceeds under mild conditions. For extension, palladium-catalyzed oxidative carbonylation of anthranilic acids was developed for the synthesis of substituted isatoic anhydrides in high to excellent yields.

18.
Front Immunol ; 15: 1402548, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39192988

RESUMEN

Background: Single nucleotide polymorphisms (SNPs) in DNA repair genes can impair protein function and hinder DNA repair, leading to genetic instability and increased cancer risk. The Excision Repair Cross-Complementation (ERCC) family plays a crucial role in nucleotide excision repair, yet their comprehensive multi-omics characterization and roles in tumor prognosis and immune microenvironment remain unexplored. Methods and materials: We performed bioinformatics analysis using publicly available data from 33 cancer types to investigate associations between ERCC gene expression, patient prognosis, and clinical features. We also validated the role of ERCC2 in bladder cancer through in vitro assays, including CCK-8, colony formation, wound healing, and Transwell assays. Results: By utilizing the most recent database, we have conducted an analysis that reveals associations between variations in ERCC expression across multiple cancer types and both patient prognosis and the tumor microenvironment. To ensure the reliability of our findings, we applied the Benjamini-Hochberg procedure to adjust for multiple testing. After correction, we identified that ERCC expression levels remained significantly correlated with patient prognosis in various cancer types (p < 0.05). In addition, according to the results of drug sensitivity studies of anticancer drugs, there is a large correlation between ERCC expression and the sensitivity of different anticancer drugs. Finally, in vitro cell behavioral assays determined that knockdown of ERCC2 gene expression significantly inhibited the proliferation, migration and invasion of bladder cancer cells. Conclusion: Through in-depth exploration of ERCC differential expression and its correlation with immune-related indicators, the unique microenvironment of tumors, and patient prognosis, we verified the potential role of ERCC2 in the process of bladder cancer genesis and progression. Therefore, we believe that the ERCC family of genes is expected to be a new option for cancer treatment and deserves to be further explored in the future.


Asunto(s)
Biología Computacional , Microambiente Tumoral , Neoplasias de la Vejiga Urinaria , Proteína de la Xerodermia Pigmentosa del Grupo D , Humanos , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/inmunología , Proteína de la Xerodermia Pigmentosa del Grupo D/genética , Biología Computacional/métodos , Pronóstico , Línea Celular Tumoral , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Regulación Neoplásica de la Expresión Génica , Proteínas de Unión al ADN/genética , Biomarcadores de Tumor/genética , Polimorfismo de Nucleótido Simple , Proliferación Celular/genética , Reparación del ADN
19.
Transl Androl Urol ; 13(6): 994-1003, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38983476

RESUMEN

Background: In recent years, despite several surgical techniques having been applied, the early incontinence rate after radical prostatectomy (RP) remains high. In this study, we reconstructed an internal urethral sphincter (IUS) with anterior bladder neck tube (ABNT) to improve early return of continence and find a more effective technique for early urinary incontinence after RP. Methods: In this study, 96 previous patients who did not receive an ABNT between October 2018 and May 2020 were compared as historical controls (the control group). A total of 210 consecutive patients underwent robotic or laparoscopic RP with ABNT between May 2020 and February 2023 (the ABNT group). The inclusion criteria included Eastern Cooperative Oncology Group (ECOG) score 0-1 and localized prostate cancer (clinical stages cT1-3, cN0, cM0). The exclusion criteria included patients with diabetes, neurologic diseases, previous pelvic operations, symptoms of urinary incontinence, prior radiation, focal therapy, or androgen deprivation therapy for prostate cancer. ABNT was reconducted with a U-shaped flap from the anterior wall of the bladder neck, and was then anastomosed with the urethra. In the control group, the bladder outlet was directly anastomosed with the urethra. Continence, as defined if 0 pads were used per day and International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) score ≤6, was assessed at 1, 4, 8, 12, and 24 weeks after catheter removal. At 2 weeks after catheter removal, urethral pressure profilometry (UPP) and upright urethrography were performed to evaluate the function of ABNT in the ABNT group. Results: More patients in the ABNT group were continent than those in the control group at 1 week (85.2% vs. 22.9%, P<0.001), 4 weeks (91.4% vs. 27.1%, P<0.001), 8 weeks (95.2% vs. 40.6%, P<0.001), 12 weeks (100% vs. 71.9%, P<0.001), and at 24 weeks (100% vs. 87.5%, P<0.001) after catheter removal. Stricture was presented in 5.2% and 2.1% (P=0.34) in the ABNT group and control group, respectively. UPP showed that a functional IUS was reconstructed with ABNT. Upright urethrography showed that the ABNT was filled with contrast medium in the urination period and with no contrast medium during the storage period and interruption of urination. Conclusions: The ABNT technique significantly improved early return of continence in comparison with the no ABNT technique, especially the immediate continence. The ABNT technique reconstructed the functional IUS with acceptable urethral stricture. The limitations of the present study include that the comparison was conducted retrospectively with a historical cohort and lack of randomization, and the single center setting. A prospective, randomized, and multicenter evaluation is expected.

20.
Chemistry ; 19(30): 9789-94, 2013 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-23775567

RESUMEN

Iodide in copper's pathway: A new, efficient, and practical copper-catalyzed synthesis of Z-iodoenamides from readily available ketoximes has been developed (see scheme). The reaction was believed to proceed through a single-electron-transfer pathway. The corresponding Z-iodoenamides have been applied to the synthesis of substituted oxazoles, dienes, ß-phenoxyl enamides, eneynes, ß-acylenamides, and pyrroles (DCE = 1,2-dichloroethane).

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