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1.
Org Lett ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073919

RESUMO

Readily accessible N-sulfonylaminophthalimides were developed to be efficient sulfonyl radical precursors upon being treated with a base/oxidant under mild conditions. The method was applied to the oxysulfonylation of olefins, providing ß-ketosulfones and isobenzofurans stereoselectively. On the basis of control experiments, density functional theory calculations, and the literature, a plausible radical mechanism was proposed. The findings offered a chance to develop novel radical precursors based on diversely substituted N-aminophthalimides, which might establish a universal mild approach for the generation of various radicals.

2.
Org Lett ; 26(26): 5453-5457, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38913009

RESUMO

A copper-catalyzed intramolecular cascade reaction of conjugated enynones has been achieved via a pivotal 1,4-sulfinate migration step. This process leverages a cost-effective and ecofriendly copper salt as catalyst, enabling the efficient construction of five- and four-membered rings in a rapid, sequential manner, producing furan-tethered benzocyclobutenes in good to excellent yields under mild conditions. The reaction is characterized by 100% atom economy, outstanding efficiency, and excellent diastereoselectivity in the cases studied. The robustness of this method is evidenced by its compatibility with air exposure and the use of undistilled, commercially available solvents, further enhancing its practicality.

3.
J Clin Biochem Nutr ; 74(3): 235-244, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38799140

RESUMO

Sirtuin 3 involved in development of various diseases, but its role in inflammatory bowel disease is still unknown. We used inflammatory bowel disease biopsies, colitis animal model, and vitro cells RAW264.7 to study the role of Sirtuin 3 in the pathophysiology of inflammatory bowel disease. Sirtuin 3 negatively correlated with intestinal TNF-α. Sirt3 was less pronounced in pediatric and adult inflammatory bowel disease patients compared with corresponding control group. Sirtuin 3 activator Honokiol suppressed dextran sulfate sodium induced colonic manifestations, while Sirt3 inhibitor caused opposite results. Honokiol inhibited colonic oxidative stress by and reduced intestinal permeability. Honokiol repressed inflammatory response by reducing macrophage infiltration, pro-inflammatory cytokines TNF-α, IL-1ß, and IL-6 levels, and inhibiting activation of NF-κB p65 in the colitis mice. However, Sirt3 inhibitor amplified colonic oxidative stress and inflammatory response. In vitro study, Sirt3 inhibitor or siRNA Sirtuin 3 activated NF-κB p65 and enhanced TNF-α, IL-1ß, and IL-6 secretion from LPS stimulated RAW264.7, while Honokiol remarkably attenuated these pro-inflammatory cytokines secretion. Finally, knockdown of Sirt3 in Caco-2 cells enhanced TNF-α induced intestinal barrier integrity injury. Sirtuin 3 negatively regulates inflammatory bowel disease progression via reducing colonic inflammation and oxidative stress. Sirtuin 3 is a promising therapeutic target in clinical application for inflammatory bowel disease therapy.

4.
Front Oncol ; 14: 1401839, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800396

RESUMO

Background: Desmoid tumor (DT) is a rare locally aggressive but non-metastatic mesenchymal soft tissue neoplasm that predominantly occurs in the abdominal wall, abdominal cavity, and extremities. Its occurrence in the mesentery is relatively uncommon. Case reports: This article reports two cases of desmoid tumor treated at the Department of Gastrointestinal Surgery, Weifang People's Hospital. The first case was a 59-year-old male patient who had previously undergone surgery for esophagogastric junction cancer. Postoperatively, he developed an intra-abdominal mass that rapidly increased in size within three months. The second case was a 60-year-old male patient who incidentally discovered a mass in the left lower abdomen. Both patients underwent surgical treatment, and the postoperative pathological diagnosis was mesenteric desmoid tumor. Conclusion: The treatment of desmoid tumor remains challenging. Simple surgical resection often yields unsatisfactory outcomes, and the efficacy of adjuvant radiotherapy and chemotherapy is also limited. Further research and clinical practice are necessary to improve diagnostic and therapeutic strategies, aiming to enhance patient survival and quality of life.

5.
J Hazard Mater ; 473: 134625, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38759408

RESUMO

Development of a biotechnological system for rapid degradation of pesticides is important to mitigate the environmental, food security, and health risks that they pose. Degradation of atrazine (ATZ) and isoproturon (IPU) in rice crops promoted by the brassinosteroid (BR) signaling component BRASSINAZOLE RESISTANT4 (OsBZR4) is explored. OsBZR4 is localized in the plasma membrane and nucleus, and is strongly induced by ATZ and IPU exposure. Transgenic rice OsBZR4-overexpression (OE) significantly enhances resistance to ATZ and IPU toxicity, improving growth, and reducing ATZ and IPU accumulation (particularly in grains) in rice crops. Genetic destruction of OsBZR4 (CRISPR/Cas9) increases rice sensitivity and leads to increased accumulation of ATZ and IPU. OE plants promote phase I, II, and III metabolic reactions, and expression of corresponding pesticide degradation genes under ATZ and IPU stress. UPLC-Q-TOF-MS/MS analysis reveals increased relative contents of ATZ and IPU metabolites and conjugates in OE plants, suggesting an increased OsBZR4 expression and consequent detoxification of ATZ and IPU in rice and the environment. The role of OsBZR4 in pesticide degradation is revealed, and its potential application in enhancing plant resistance to pesticides, and facilitating the breakdown of pesticides in rice and the environment, is discussed.


Assuntos
Atrazina , Brassinosteroides , Oryza , Compostos de Fenilureia , Plantas Geneticamente Modificadas , Oryza/metabolismo , Oryza/genética , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/metabolismo , Brassinosteroides/metabolismo , Atrazina/toxicidade , Atrazina/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Herbicidas/metabolismo , Herbicidas/toxicidade , Biodegradação Ambiental , Transdução de Sinais/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
6.
Medicine (Baltimore) ; 103(8): e37223, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394531

RESUMO

INTRODUCTION: Perineal hernia (PH) is a rare complication that can occur after abdominoperineal resection for rectal cancer. Laparoscopic repair of PHs has gained increasing popularity compared to open approaches due to advantages such as superior visualization, decreased invasiveness, and faster recovery. This case report highlights the successful use of laparoscopic tension-free mesh repair for concurrent perineal and inguinal hernias after rectal cancer surgery. CASE DESCRIPTION: A 51-year-old man underwent laparoscopic-assisted abdominoperineal resection for rectal cancer. About 2 months postoperatively, he developed reducible masses in the perineal and left groin regions, associated with urinary symptoms and sensation of prolapse. Physical exam revealed protruding masses that enlarged with Valsalva. Pelvic CT confirmed PH and left inguinal hernia. INTERVENTIONS: Laparoscopic tension-free repair of the PH and inguinal hernia was performed on this patient. The repair was completed by the steps of adhesion separation, mesh placement, and fixation. OUTCOMES: The 98-minute surgery was successful without complications. The patient recovered well, ambulating on postoperative day 2 and getting discharged on day 6. CONCLUSION: This case demonstrates that laparoscopic tension-free repair with mesh is an effective approach for treating PH and concurrent inguinal hernia following rectal cancer surgery, resulting in successful outcomes and low recurrence rates. The laparoscopic technique provides benefits of minimal invasiveness and rapid recovery.


Assuntos
Hérnia Abdominal , Hérnia Inguinal , Laparoscopia , Neoplasias Retais , Masculino , Humanos , Pessoa de Meia-Idade , Hérnia Inguinal/cirurgia , Hérnia Abdominal/cirurgia , Reto/cirurgia , Neoplasias Retais/cirurgia , Laparoscopia/efeitos adversos , Herniorrafia/métodos , Telas Cirúrgicas/efeitos adversos
7.
Org Lett ; 26(4): 883-888, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38252691

RESUMO

Herein, we present a transition-metal-free, easy handling protocol for regioselective carboxylation of gem-difluorostyrenes with sodium formate as the C1 source. 30 examples of α-fluoracrylates were obtained in yields of 30 to 80% under these conditions. A defluorinative monofluorovinyl intermediate and consecutive photoinduced electron transfer mechanism were proposed after mechanism investigation.

8.
J Agric Food Chem ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37905821

RESUMO

The rice cytochrome P450 gene has been comprehensively studied in the present study. This gene encodes CYP90D5 in promoting the degradation of isoproturon (IPU) and acetochlor (ACT) in rice tissues and grains. It has here been found that CYP90D5 improved the resistance of the plant to IPU and ACT, which was reflected in the improvement of the growth of the overexpression (OE) lines. CYP90D5 also reduced the levels of IPU and ACT accumulation in rice, and the CRISPR-Cas9 (Cas9) lines displayed the opposite effects. This function of CYP90D5 for pesticide degradation was also confirmed by the transformation of CYP90D5 in Pichia pastoris. Compared with the control yeast, it grew better and could degrade more pesticides. In addition, the relative contents of the IPU and ACT derivatives increased in the OE rice, while they decreased in the Cas9 rice. This suggested that CYP90D5 plays a pivotal role in the pesticide detoxification and degradation.

9.
Org Biomol Chem ; 21(29): 5935-5938, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37435711

RESUMO

A facile and efficient synthetic method for 3-aminoquinolines has been reported. The straightforward process starts from easily available triazoles and 2-aminobenzaldehydes. Low catalyst loading and good functional group compatibility are the other two merits of this transformation. Easy decoration of the 3-aminoquinoline motifs enabled the convenient synthesis of bioactive molecules, demonstrating the potential of this protocol in organic synthesis.

10.
J Org Chem ; 88(13): 9543-9553, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37307412

RESUMO

A catalyst-free cascade reaction of 3-(2-isocyanoethyl)indoles and 1-sulfonyl-1,2,3-triazoles was realized. This dearomative spirocyclization provided an efficient protocol to synthesize a series of polycyclic indolines bearing spiro-α-carboline in moderate to high yields in one step under thermal reaction conditions.


Assuntos
Indóis , Triazóis , Estereoisomerismo , Catálise
11.
Org Lett ; 25(26): 4886-4891, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37350627

RESUMO

Valuable piperidin-4-one derivatives were synthesized in excellent yields via an α-imino carbene-initiated cascade reaction involving 1,2-aryl/alkyl migration and annulation. The excellent selectivity of alkyl migration was attributed to the neighboring group participation of 2-bromoethyl. Features such as high efficiency, excellent migrating selectivity, broad substrate scope, and convenient one-pot procedure qualified this protocol as an effective tool for piperidine derivative synthesis. The product could be transformed to a bioactive molecule easily. The migration-annulation reaction of α-imino carbene provided a powerful strategy for heterocycle construction.

12.
J Econ Entomol ; 116(4): 1329-1341, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37253084

RESUMO

Fall armyworm, Spodoptera frugiperda (J. E. Smith), has become an important agricultural pest worldwide. S. frugiperda is mainly controlled by the chemical insecticides, whereas the frequent application of insecticides would result in the resistance development. Insect uridine diphosphate-glucuronosyltransferases (UGTs), as phase II metabolism enzymes, play vital roles in the breakdown of endobiotic and xenobiotics. In this study, 42 UGT genes were identified by RNA-seq, including 29 UGT genes were elevated compared to the susceptible population, and the transcript levels of 3 UGTs (UGT40F20, UGT40R18, and UGT40D17) were increased by more than 2.0-fold in the field populations. Expression pattern analysis revealed that S. frugiperda UGT40F20, UGT40R18, and UGT40D17 were increased by 6.34-, 4.26-, and 8.28-fold, compared the susceptible populations, respectively. The expression of UGT40D17, UGT40F20, and UGT40R18 was affected after exposure to phenobarbital, chlorpyrifos, chlorfenapyr, sulfinpyrazone, and 5-nitrouracil. The induced expression of UGT genes may have improved UGT enzymatic activity, while the inhibition of UGTs genes expression may decreased UGT enzymatic activity. Sulfinpyrazone, and 5-nitrouracil, significantly increased the toxicity of chlorpyrifos and chlorfenapyr, as well as phenobarbital significantly reduced the toxicity of chlorpyrifos and chlorfenapyr against the susceptible populations and field populations of S. frugiperda. The suppression of UGTs (UGT40D17, UGT40F20, and UGT40R18) significantly increased the insensitivity of the field populations to chlorpyrifos and chlorfenapyr. These findings strongly supported our viewpoint that UGTs may play a critical role in insecticide detoxification. This study provides a scientific basis for the management of S. frugiperda.


Assuntos
Clorpirifos , Inseticidas , Mariposas , Animais , Spodoptera/genética , Inseticidas/farmacologia , Clorpirifos/farmacologia , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Sulfimpirazona , Resistência a Inseticidas/genética , Mariposas/genética , Mariposas/metabolismo , Larva
13.
Org Lett ; 25(12): 2145-2150, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36921249

RESUMO

Here, we disclose a general approach for the diverse synthesis of alkenylsilanes in a highly efficient, stereoselective, and atom-economic manner by leveraging the palladium-catalyzed disilylation reaction of 2-bromostyrene derivatives with hexamethyldisilane, which is suitable for the preparation of a series of disubstituted, trisubstituted, and tetrasubstituted alkenylsilanes. Furthermore, the resulting tetrasubstituted alkenylsilanes could be readily transformed into the corresponding diarylated benzosiloles, which have been proven to be a potential AIE material and a fluorene material.

14.
Chem Commun (Camb) ; 58(87): 12244-12247, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36254714

RESUMO

Triggered by formation of α-imino carbene, the regioselective synthesis of dihydropyrroles was achieved via a cascade 1,3-sulfinate migration/annulation. The sulfinate group was converted into sulfone during the group migration, and a stable anion bearing two electron-withdrawing groups was thus formed. The addition of a catalytic amount of iodide is believed to assist the cleavage of the C-O bond, and the formation of a more stable carbocation. Thermodynamic product dihydropyrroles were produced efficiently rather than kinetic product cyclopropanes. This dual catalysis system would afford chemists a new strategy to control the annulation selectivity of zwitterions bearing multiple reactive sites and may be employed in flexible and divergent synthesis of different ring systems.


Assuntos
Ciclopropanos , Pirróis , Catálise , Pirróis/química , Ciclização , Ciclopropanos/química
15.
Org Lett ; 24(39): 7118-7122, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36153761

RESUMO

Herein, a photoinitiated radical relay reaction of quinoxalin-2(1H)-ones, with acyloxy nitroso compounds as a source of radicals, is described. Although the C-H functionalization of quinoxalin-2(1H)-ones has been investigated, its difunctionalization, the simultaneous construction of C-C and N-N bonds directly via the radical relay reaction, has rarely been reported. Moreover, the obtained products underwent sequential reactions to access C7-NO2 of quinoxalin-2(1H)-ones under mild conditions.

16.
Org Lett ; 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35852457

RESUMO

Formal 1,3-migration of hydroxy and acyloxy groups initiated by α-imino rhodium carbene was achieved, and the following selective annulations of the corresponding zwitterions could efficiently afford azepane derivatives. Benefiting from a time-saving procedure as well as a good functional group tolerance, this unique migration-annulation protocol could provide an efficient tool for synthesizing seven-membered N-heterocycles. The plausible mechanism is discussed.

17.
Org Lett ; 24(15): 2950-2954, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35416678

RESUMO

Formal intramolecular 1,3-OH migration of α-imino carbene was achieved producing a unique zwitterion, and the subsequent selective annulation afforded α-amino cyclobutanone. Features such as readily available substrates, mild reaction conditions, a time-saving procedure, excellent functional group compatibility, and valuable transformations of the products qualified this unique protocol as an efficient tool for the synthesis of strained cyclic compounds. Density functional theory calculations were in good agreement with experimental observations, and a plausible mechanism is presented.


Assuntos
Ródio , Catálise , Metano/análogos & derivados , Metano/química , Ródio/química
18.
Org Biomol Chem ; 20(14): 2802-2807, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35311858

RESUMO

Tetrahydrocarbazoles and pyrrolo[3,4-b]carbazoles could be synthesized conveniently through sequential reactions of ester-tethered 1-sulfonyl-1,2,3-triazoles and indoles. The reaction conditions were mild and the procedures were quite simple. Moreover, the key intermediate α,ß-unsaturated imine acted as a [2C] synthon in the [4 + 2] cycloaddition reaction, and the imino group could be used as a nucleophile to construct the fourth ring.


Assuntos
Carbazóis , Indóis , Reação de Cicloadição , Ésteres , Triazóis
19.
Org Biomol Chem ; 19(26): 5758-5761, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34124725

RESUMO

A facile synthesis of multi-functionalized benzothiazonine was achieved by the rhodium-catalyzed denitrogenative annulation of 1-sulfonyl-1,2,3-triazole and thiochromone. In view of the excellent atom economy, broad substrate scope and easy availability of starting materials, the protocol provided an efficient strategy for the construction of medium N,S-heterocycles.

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