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1.
Mediators Inflamm ; 2024: 4465592, 2024.
Article in English | MEDLINE | ID: mdl-38707705

ABSTRACT

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.


Subject(s)
Colorectal Neoplasms , Laparoscopy , Neutrophils , Postoperative Complications , Prealbumin , Humans , Colorectal Neoplasms/surgery , Male , Female , Middle Aged , Aged , Prognosis , Prealbumin/metabolism , Risk Factors , Disease-Free Survival , Adult , Multivariate Analysis , Logistic Models
2.
J Am Chem Soc ; 146(19): 12883-12888, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38709642

ABSTRACT

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.

3.
Angew Chem Int Ed Engl ; : e202406226, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38618886

ABSTRACT

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.
Org Lett ; 25(45): 8110-8115, 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-37921830

ABSTRACT

The current investigation presents an innovative palladium-catalyzed asymmetric carbonylative Heck esterification method. This approach facilitates the efficient synthesis of various chiral γ-ketoacid esters by utilizing o-alkenyliodobenzenes and arylboronic acids as primary substrates. This reaction achieves the creation of three carbon-carbon bonds, two carbon-oxygen bonds, and the establishment of a quaternary carbon center within a single step. The α-chiral γ-ketoacid esters were obtained in yields ranging from good to high yields, displaying enantiomeric excesses (ee's) levels up to 92% under mild reaction conditions.

5.
Macromol Rapid Commun ; 44(20): e2300281, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37543181

ABSTRACT

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.


Subject(s)
Polyurethanes , Smart Materials , Humidity , Bionics , Polyethylene Glycols , Polymers
6.
Nat Commun ; 14(1): 3167, 2023 May 31.
Article in English | MEDLINE | ID: mdl-37258529

ABSTRACT

Novel strategy for acid chlorides formation that do not use carboxylic acids is particularly attractive in chemical synthesis but remains challenging. Herein, we reported the development of a highly effective Pd-catalyzed hydrochlorocarbonylation of alkenes with CO for the formation of alkyl acid chlorides. Chlorosilane and AcOH were found as a mild HCl source for the reaction. The reaction shows broad substrate scope and produces both branched and linear alkyl acid chlorides in good to high yields upon different ligands and solvents. Cooperating with follow-up acylation reactions, the Pd-catalyzed hydrochlorocarbonylation offers a complementary platform for the synthesis of diverse carbonyl compounds from alkenes. Mechanistic investigations suggested that the reaction proceeded though a palladium hydride pathway, and CO prompted reductive elimination of the acyl-Pd-Cl intermediate.

7.
Nat Commun ; 14(1): 2572, 2023 May 04.
Article in English | MEDLINE | ID: mdl-37142571

ABSTRACT

Activation and cleavage of carbon-carbon (C-C) bonds is a fundamental transformation in organic chemistry while inert C-C bonds cleavage remains a long-standing challenge. Retro-Diels-Alder (retro-DA) reaction is a well-known and important tool for C-C bonds cleavage but less been explored in methodology by contrast to other strategies. Herein, we report a selective C(alkyl)-C(vinyl) bond cleavage strategy realized through the transient directing group mediated retro-Diels-Alder reaction of a six-membered palladacycle, which is obtained from an in situ generated hydrazone and palladium hydride species. This unprecedented strategy exhibits good tolerances and thus offers new opportunities for late-stage modifications of complex molecules. DFT calculations revealed that an intriguing retro-Pd(IV)-Diels-Alder process is possibly involved in the catalytic cycle, thus bridging both Retro-Diels-Alder reaction and C-C bond cleavage. We anticipate that this strategy should prove instrumental for potential applications to achieve the modification of functional organic skeletons in synthetic chemistry and other fields involving in molecular editing.

8.
Org Lett ; 25(15): 2571-2576, 2023 Apr 21.
Article in English | MEDLINE | ID: mdl-37023046

ABSTRACT

Herein, we report a palladium-catalyzed hydroalkoxycarbonylation and hydroxycarbonylation of cyclopent-3-en-1-ols to form bridged bicyclic lactones and ß,γ-unsaturated carboxylic acid. The divergent reactivity of cyclopent-3-en-1-ols is mainly tuned by the palladium catalyst and ligands. The reaction occurs additive-free and has a broad substrate scope. Several valuable synthetic and medical intermediates are accessible through this protocol.

9.
Org Lett ; 24(35): 6397-6401, 2022 09 09.
Article in English | MEDLINE | ID: mdl-36018318

ABSTRACT

An asymmetric organocatalyzed three-component Povarov reaction to construct azaspirocycles has been developed. A chiral phosphoric acid OCF-CPA bearing o-CF3-aryl on the H8-BINOL-framework is highly efficient in the reaction. The reaction was carried out under mind conditions for synthesis of a range of azaspirocycles in high yields and high to excellent enantioselectivities, thus expending the substrate scope of the traditional Povarov reaction.


Subject(s)
Stereoisomerism , Catalysis
10.
J Cancer ; 13(7): 2138-2149, 2022.
Article in English | MEDLINE | ID: mdl-35517427

ABSTRACT

Docetaxel resistance seriously affects its clinical application in prostate cancer (PCa). Long noncoding RNAs (lncRNAs) influence the chemosensitivity of various cancers. However, the potential involvement of lncRNAs in docetaxel sensitivity remains largely unknown in PCa. In the present study, we used RNA sequencing to compare the expression profiles of lncRNAs in docetaxel-resistant PCa cells and their parental cells and identified a novel lncRNA, ENSG00000234147, termed as PCa docetaxel resistance-associated lncRNA1 (PCDRlnc1). Our results indicated that PCDRlnc1 is closely associated with docetaxel resistance in PCa, and PCDRlnc1 knockout markedly sensitized the resistant cells to docetaxel in vitro and in vivo. In addition, PCDRlnc1 inhibition markedly suppressed docetaxel-induced autophagy. Conversely, PCDRlnc1 overexpression promoted autophagy. Mechanistically, PCDRlnc1 interacted with UHRF1 (ubiquitin-like with plant homeodomain and ring finger domains 1) and promoted its transcription level in PCa cells, leading to the activation of autophagic Beclin-1 signaling. Together, our data demonstrate that PCDRlnc1 is a novel key regulator of PCa docetaxel resistance, suggesting that it may be used as a potential biomarker of docetaxel resistance and therapeutic target in PCa.

11.
Zhonghua Nan Ke Xue ; 28(10): 886-890, 2022 Oct.
Article in Chinese | MEDLINE | ID: mdl-37838954

ABSTRACT

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.


Subject(s)
Laparoscopy , Urinary Incontinence , Male , Humans , Urinary Bladder/surgery , Urinary Incontinence/prevention & control , Urinary Incontinence/surgery , Prostatectomy/adverse effects , Prostatectomy/methods , Urethra/surgery , Laparoscopy/methods , Recovery of Function
12.
Org Lett ; 23(23): 9241-9245, 2021 12 03.
Article in English | MEDLINE | ID: mdl-34767367

ABSTRACT

Rhodium-catalyzed asymmetric desymmetrization Pauson-Khand reaction of C4-alkynyl-tethered cyclohexadienones has been developed as a novel strategy for access to fused 6-5-5 tricycles bearing three consecutive stereogenic centers. An array of chiral tricyclo[6.2.1.04,11]undecenes have been synthesized in high yields and enantioselectivities in a single step under mild conditions. This strategy employs readily accessible internal-olefin-containing 1,6-enynes, providing a potentially powerful tool for constructing chiral polycyclic scaffolds of complex molecules containing cyclopentenones and cyclohexenones.

13.
Sci Rep ; 11(1): 20754, 2021 10 21.
Article in English | MEDLINE | ID: mdl-34675270

ABSTRACT

Silver nanoparticles (Ag. NPs) have shown a biological activity range, synthesized under different environment-friendly approaches. Ag. NPs were synthesized using aqueous crude extract (ACE) isolated from Plantago lanceolata. The ACE and Ag. NPs were characterized and assessed their biological and antioxidant activities. The existence of nanoparticles (NPs) was confirmed by color shift, atomic force microscopy (AFM), and UV-Vis's spectroscopy. The FT-IR analysis indicated the association of biomolecules (phenolic acid and flavonoids) to reduce silver (Ag+) ions. The SEM study demonstrated a sphere-shaped and mean size in the range of 30 ± 4 nm. The EDX spectrum revealed that the Ag. NPs were composed of 54.87% Ag with 20 nm size as identified by SEM and TEM. AFM has ended up being exceptionally useful in deciding morphological elements and the distance across of Ag. NPs in the scope of 23-30 nm. The TEM image showed aggregations of NPs and physical interaction. Ag. NPs formation also confirmed by XPS, DRS and BET studies. Ag. NPs showed efficient activity as compared to ACE, and finally, the bacterial growth was impaired by biogenic NPs. The lethal dose (LD50) of Ag. NPs against Agrobacterium tumefaciens, Proteus vulgaris, Staphylococcus aureus, and Escherichia coli were 45.66%, 139.71%, 332.87%, and 45.54%, with IC50 (08.02 ± 0.68), (55.78 ± 1.01), (12.34 ± 1.35) and (11.68 ± 1.42) respectively, suppressing the growth as compared to ACE. The antioxidant capacity, i.e., 2,2-diphenyl-1-picrylhydrazyl (DPPH) of Ag. NPs were assayed. ACE and Ag. NPs achieved a peak antioxidant capacity of 62.43 ± 2.4 and 16.85 ± 0.4 µg mL-1, compared to standard (69.60 ± 1.1 at 100 µg mL-1) with IC50 (369.5 ± 13.42 and 159.5 ± 10.52 respectively). Finally, the Ag. NPs synthesized by P. lanceolata extract have an excellent source of bioactive natural products (NP). Outstanding antioxidant, antibacterial activities have been shown by NPs and can be used in various biological techniques in future research.


Subject(s)
Anti-Bacterial Agents/chemistry , Antioxidants/chemistry , Metal Nanoparticles/chemistry , Plantago/chemistry , Silver/chemistry , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/pharmacology , Antioxidants/chemical synthesis , Antioxidants/pharmacology , Bacteria/drug effects , Bacterial Infections/drug therapy , Humans , Metal Nanoparticles/ultrastructure , Nanotechnology
14.
Angew Chem Int Ed Engl ; 60(43): 23117-23122, 2021 10 18.
Article in English | MEDLINE | ID: mdl-34240535

ABSTRACT

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.

15.
J Am Chem Soc ; 143(19): 7298-7305, 2021 05 19.
Article in English | MEDLINE | ID: mdl-33970621

ABSTRACT

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.

16.
J Am Chem Soc ; 143(1): 85-91, 2021 01 13.
Article in English | MEDLINE | ID: mdl-33373216

ABSTRACT

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.

17.
J Org Chem ; 85(12): 7939-7951, 2020 06 19.
Article in English | MEDLINE | ID: mdl-32441101

ABSTRACT

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.

18.
Angew Chem Int Ed Engl ; 59(29): 12199-12205, 2020 07 13.
Article in English | MEDLINE | ID: mdl-32239787

ABSTRACT

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.

20.
Org Lett ; 20(12): 3627-3630, 2018 06 15.
Article in English | MEDLINE | ID: mdl-29863885

ABSTRACT

A K2S2O8/TEMPO-induced oxidative cyclization of N-unprotected enaminoesters and enaminones that gave 1 H-pyrrol-2(3 H)-ones in good yields with broad functional group compatibility is reported. This method provides easy access to 1,2-carbon migration of ester or acyl group under transition-metal-free conditions.

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