Recent advances in palladium-catalyzed sulfonylation via SO2 insertion.

The importance of sulfonyl-group-containing compounds, such as sulfonamides, sulfones, sulfinate esters, and sulfonyl fluorides, in pharmaceuticals, bioactive molecules, and natural products cannot be overstated. The new development of palladium-catalyzed sulfonylation via SO2 insertion represents a crucial advancement in organic synthesis, enabling the direct α,α-difunctionalization of SO2 and providing efficient access to an array of structure-diverse sulfonyl-containing compounds. Although there have been numerous reviews about SO2 insertion, many of them only cover specific aspects of palladium-catalyzed reactions, leading to an oversight of some important works. Besides, these reviews often lack detailed discussions and systematic conclusion on reaction mechanisms, and fail to comprehensively summarize the significant research achievements in palladium-catalyzed reactions over the past few years. Herein, we aim to systematically consolidate the recent advances in palladium-catalyzed sulfonylation via SO2 insertion, elucidate the underlying reaction mechanism, and highlight some unsolved challenges in this segment. This review seeks to serve as a valuable resource for researchers, assisting in the continued development of palladium-catalyzed sulfonylation methodologies.

Regio- and Diastereoselective Hydrophosphination and Hydroamidation of gem-Difluorocyclopropenes.

In this study, concise, efficient, and modular hydrophosphinylation and hydroamidation of gem-difluorocyclopropenes were disclosed in a mild and transition-metal-free pattern. Through this approach, phosphorus, and nitrogen-containing gem-difluorocyclopropanes were produced in moderate to good yields with excellent regio- and diastereoselectivity. Readily available gem-difluorocyclopropenes and nucleophilic reagents, along with inexpensive inorganic bases, were employed. Multiple synthetic applications, including gram-scale and derivatization reactions and modification of bioactive molecules, were subsequently elaborated.

Modular Synthesis of 1,2-Benzothiazines and 1,2-Benzothiazine 1-Imines via Palladium-Catalyzed C-H/C-C Activation Reactions.

In this study, a modular approach toward cyclic sulfoximines and sulfondiimines via palladium-catalyzed intramolecular C-H/C-C activation reactions was reported. Various 1,2-benzothiazines including bicyclic, tricyclic, highly fused ones, ones of the seven-membered ring, along with 1,2-benzothiazine 1-imines were accessed in good yields. KIE experiment demonstrated that the C-H bond cleavage at the position ortho to the sulfoximine group is not the rate-determining step in the coupling reaction.

Effect of ropivacaine combined with dexmedetomidine in transversus abdominis plane block on postoperative stress hormone and cognitive function in patients undergoing laparoscopic radical gastrectomy / 新乡医学院学报

Objective To explore the effect of ropivacaine combined with dexmedetomidine in transversus abdominis plane block(TAPB)on postoperative stress hormones and cognitive function in patients undergoing laparoscopic radical gastrectomy.Methods A total of 80 patients undergoing laparoscopic radical gastrectomy at the First Affiliated Hospital of Xinxiang Medical University from April to October 2023 were selected as the research subjects.According to different anesthesia methods,the patients were divided into the observation group and the control group,with 40 patients in each group.Patients in the observation group were injected bilaterally with 2.5 g·L-1 ropivacaine and 0.5 μg·kg-1 dexmedetomidine for TAPB,with 20 mL injection on each side.Patients in the control group were injected bilaterally with 2.5 g·L-1 ropivacaine for TAPB,with 20 mL injection on each side.Mean arterial pressure(MAP)and heart rate(HR)were recorded at the time of admission to the operating room(T1),immediately after endotracheal intubation(T2),40 minutes after pneumoperitoneum(T3),and 15 minutes after extubation(T4).Radioimmunoprecipitation was used to detect serum cortisol(COR)level,and enzyme-linked immunosorbent assay was used to measure serum norepinephrine(NE)and epinephrine(E)levels at 1,6,12,and 24 hours after surgery.Visual analog scale(VAS)was used to assess pain at rest,and Ramsay sedation scale(RSS)was used to evaluate sedation depth.The doses of propofol and sufentanil were compared between the two groups.Serum β-amyloid(Aβ)and S100β protein levels at 1 day before surgery,1 and 3 days after surgery were detected by using the enzyme-linked immunosorbent assay,and cognitive function was assessed at the same time points by using the mini-mental state examination(MMSE).Results At T,and T2,there was no significant difference in MAP and HR between the control group and the observation group(P＞0.05).At T3 and T4,MAP and HR in the observation group were significantly lower than those in the control group(P＜0.05).At 1,6,and 12 hours postoperatively,VAS score in the observation group was significantly lower than that in the control group(P＜0.05).At 24 hours postoperatively,there was no significant difference in VAS score between the control group and observation group(P＞0.05).At 1 and 6 hours postoperatively,RSS score in the observation group was significantly higher than that in the control group(P＜0.05).At 12 and 24 hours postoperatively,there was no significant difference in RSS score between the control group and observation group(P＞0.05).At 1,6,and 12 hours postoperatively,COR,NE,and E levels in the observation group were significantly lower than those in the control group(P＜0.05).At 24 hours postoperatively,there was no significant difference in COR,NE,and E levels between the control group and observation group(P＞0.05).The doses of propofol and sufentanil in the observation group were significantly lower than those in the control group(P＜0.05).One day before surgery,there was no significant difference in MMSE score between the control group and observation group(P＞0.05).At 1 and 3 days postoperatively,MMSE score in the observation group was significantly higher than that in the control group(P＜0.05).One day before surgery,there was no significant difference in serum Aβ and S100β protein levels between the control group and observation group(P＞0.05).At 1 and 3 days postoperatively,serum Aβ and S100β protein levels in the observation group were significantly lower than those in the control group(P＜0.05).Conclusion Ropivacaine combined with dexmedetomidine in TAPB in radical gastrectomy can significantly reduce postoperative pain,increase sedative effect,prolong the duration of TAPB,and benefit patients'postoperative recovery with reduced cognitive impairment.

Effect of superior cervical ganglion block on cardiac function and NLRP3 signaling pathway in a rat model of myocardial ischemia-reperfusion / 中华麻醉学杂志

Objective:To evaluate the effect of superior cervical ganglion block (SCGB) on cardiac function and nucleotide like receptor protein 3 (NLRP3) signaling pathway in a rat model of myocardial ischemia-reperfusion (I/R).Methods:Sixty healthy SPF male Sprague-Dawley rats, weighing 250-300 g, aged 2-3 months, were divided into 4 groups ( n=15 each) using a random number table method: sham operation group (sham group), myocardial I/R group (IR group), myocardial I/R + normal saline group (IR+ NS group), and myocardial I/R + SCGB group (IR+ SCGB group). Myocardial I/R model was developed by ligation of the left anterior descending branch of the coronary artery for 45 min followed by restoration of blood flow in anesthetized aninals. IR+ SCGB group received SCGB (0.25% ropivacaine 0.1 ml) at 10 min before reperfusion once a day for 2 consecutive weeks, while 0.9% sodium chloride was given instead of ropivacaine in IR+ NS group. Blood samples were collected at 24 h and 14 days of reperfusion for determination of serum concentrations of norepinephrine (NE), troponin T (TnT), tumor necrosis factor-alpha (TNF-α), interleukin-18 (IL-18) and IL-1β by enzyme-linked immunosorbent assay. Echocardiography was performed before ischemia and at 14 days of reperfusion, and left ventricular short axis shortening rate (FS), ejection fraction (EF), and cardiac output (CO) were measured. The rats were sacrificed at 14 days of reperfusion and the hearts were taken for determination of the contents of norepinephrine (NE) in myocardial tissues in the infarction area (by enzyme-linked immunosorbent assay), percentage of myocardial fibrosis area (by Masson staining), M1 macrophage marker CD68 + cell count in the infarction area (by immunohistochemical method), and expression of NLRP3 and gasdermin D (GSDMD) in myocardial tissues (by Western blot). Results:Compared with Sham group, the serum concentrations of TnT, TNF-α, IL-18 and IL-1β, percentage of myocardial fibrosis area, and NE levels in serum and myocardial tissues were significantly increased, the expression of NLRP3 and GSDMD in myocardial tissues was up-regulated, CD68 + cell count was increased, and EF, CO and FS were decreased in IR group ( P<0.05). Compared with IR group, the serum concentrations of TnT, TNF-α, IL-18 and IL-1β, percentage of myocardial fibrosis area, and NE levels in serum and myocardial tissues were significantly decreased, the expression of NLRP3 and GSDMD in myocardial tissues was down-regulated, CD68 + cell count was decreased, and EF, CO and FS were increased in IR+ SCGB group ( P<0.05), and no statistically significant changes were found in the parameters mentioned above in IR+ NS group ( P>0.05). Conclusions:SCGB can improve the cardiac function in a rat model of myocardial I/R, and the mechanism may be related to the inhibition of NLRP3 signaling pathway.

Chiral phosphoric acid-catalyzed dual-ring formation for enantioselective construction of N-N axially chiral 3,3'-bisquinazolinones.

In contrast with the well-developed C-C and C-N axial chirality, research focusing on the catalytically asymmetric synthesis of N-N axially chiral compounds is still limited. As a privileged subunit of many antibiotics, the synthesis of N-N axially chiral 3,3'-bisquinazolinones has not been updated with atroposelective construction. Herein, we firstly report a chiral phosphoric acid-catalyzed dual-ring formation strategy leading to the aforementioned compounds with good chemical yields and enantioselectivities. Notably, metal-free reaction conditions are another advantage of this procedure.

Visible-Light Photosynthesis of CHF2 /CClF2 /CBrF2 -Substituted Ring-fused Quinazolinones in Dimethyl Carbonate.

With eco-friendly and sustainable CO2 -derived dimethyl carbonate as the sole solvent, the visible-light-induced cascade radical reactions have been established as a green and efficient tool for constructing various CHF2 /CClF2 /CBrF2 -substituted ring-fused quinazolinones.

Image segmentation of skin lesions based on dense atrous spatial pyramid pooling and attention mechanism / 生物医学工程学杂志

The skin is the largest organ of the human body, and many visceral diseases will be directly reflected on the skin, so it is of great clinical significance to accurately segment the skin lesion images. To address the characteristics of complex color, blurred boundaries, and uneven scale information, a skin lesion image segmentation method based on dense atrous spatial pyramid pooling (DenseASPP) and attention mechanism is proposed. The method is based on the U-shaped network (U-Net). Firstly, a new encoder is redesigned to replace the ordinary convolutional stacking with a large number of residual connections, which can effectively retain key features even after expanding the network depth. Secondly, channel attention is fused with spatial attention, and residual connections are added so that the network can adaptively learn channel and spatial features of images. Finally, the DenseASPP module is introduced and redesigned to expand the perceptual field size and obtain multi-scale feature information. The algorithm proposed in this paper has obtained satisfactory results in the official public dataset of the International Skin Imaging Collaboration (ISIC 2016). The mean Intersection over Union (mIOU), sensitivity (SE), precision (PC), accuracy (ACC), and Dice coefficient (Dice) are 0.901 8, 0.945 9, 0.948 7, 0.968 1, 0.947 3, respectively. The experimental results demonstrate that the method in this paper can improve the segmentation effect of skin lesion images, and is expected to provide an auxiliary diagnosis for professional dermatologists.

Ultrasound-Assisted Iodination of Imidazo[1,2-α]pyridines Via C-H Functionalization Mediated by tert-Butyl Hydroperoxide.

A novel metal catalyst-free and environmentally friendly method for the regioselective iodination of imidazo[1,2-α]pyridines at their C3 position is disclosed, which has a wide substrate scope and could be sustainable. This reaction proceeds through ultrasound acceleration in the presence of a green alcohol solvent. Compared with a conventional heating system, the reaction efficiency and the rate are significantly improved and the iodine atom economy is maximized using ultrasound techniques.

Photoinduced efficient synthesis of cyanoalkylsulfonylated oxindoles via sulfur dioxide insertion.

A visible-light-promoted radical cascade reaction of N-arylacrylamide and cyclobutanone oxime esters with sulfur dioxide insertion is established. Mainly through the exploration of the visible light wavelength, it is found that the light source has a certain influence on the formation of cyanoalkylsulfonylated oxindoles, furnishing a range of sulfones in good to excellent yields. This protocol presents good functional group compatibility and does not require transition metals, photosensitizers, external bases, or oxidants.

Electrochemically promoted oxidative α-cyanation of tertiary and secondary amines using cheap AIBN.

The electrochemical α-cyanation of tertiary and secondary amines has been developed by using a cheap cyanide reagent, azobisisobutyronitrile (AIBN). The CN radical, generated through n-Bu4NBr-meidated electrochemical oxidation, participates in a novel α-cyanation reaction under exogenous oxidant-free conditions.

Palladium-Catalyzed Atroposelective Coupling-Cyclization of 2-Isocyanobenzamides to Construct Axially Chiral 2-Aryl- and 2,3-Diarylquinazolinones.

A palladium-catalyzed imidoylative cycloamidation of N-alkyl-2-isocyanobenzamides with 2,6-disubstituted aryl iodides, affording unprecedented axially chiral 2-arylquinazolinones, has been developed with good yields and atroposelectivities. In this coupling-cyclization process, the biaryl linkage and the heteroaromatic ring are formed sequentially in one step. When N-(2,4-dimethoxyphenyl)-2-isocyanobenzamide is applied as a substrate, 2,3-diarylquinazolinones containing two stereogenic axes are produced with moderate diastereoselectivity and good enantioselectivities.

Effects of stellate ganglion block on activation of M1 microglia during cerebral ischemia-reperfusion in rats / 中华麻醉学杂志

Objective:To evaluate the effects of stellate ganglion block (SGB) on the activation of M1 microglia during cerebral ischemia-reperfusion (I/R) in rats.Methods:Fifty-four SPF healthy male Sprague-Dawley rats, aged 8-10 weeks, weighing 240-270 g, were divided into 3 groups ( n=18 each) using a random number table method: sham operation group (group Sham), cerebral I/R group (group IR) and SGB group.Blood vessels were only exposed, without occlusion in group Sham.Cerebral I/R was induced by occlusion of the middle cerebral artery for 90 min followed by reperfusion in group IR.Cervical sympathetic trunk transaction was performed to induce left SGB immediately after onset of reperfusion in group SGB.Blood samples were collected from the apex of the heart at 6, 12 and 24 h of reperfusion for determination of the concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β in the serum (using enzyme-linked immunosorbent assay). The animals were sacrificed after the neurological function was evaluated at 24 of reperfusion, and brain tissues were removed for microscopic examination of the pathological changes in cortex, for determination of percentage of cerebral infarct size (by TTC staining), for assessment of cell apoptosis and apoptosis rate in cortex (by TUNEL), and for determination of the expression of microglial biomarker Iba-1 and activated M1 microglia biomarker CD68 (by Western blot). Results:Compared with group Sham, the neurological function score, percentage cerebral infarct size, apoptosis rate in cortex, concentrations of TNF-α, IL-6 and IL-1β in the serum, and the expression of Iba-1 and CD68 were significantly increased in IR and SGB groups ( P<0.05). Compared with group IR, the neurological function score, percentage cerebral infarct size, apoptosis rate in cortex, concentrations of TNF-α, IL-6 and IL-1β in the serum, and the expression of Iba-1 and CD68 were significantly decreased in group SGB ( P<0.05), and the pathological changes of brain tissues were significantly attenuated in group SGB. Conclusion:The mechanism by which SGB reduces cerebral I/R injury is related to inhibiting activation of M1 microglia in rats.

Relay Palladium/Copper Catalysis Enabled Silylative [5 + 1] Benzannulation Using Terminal Alkynes as One-Carbon Units.

Using terminal alkyne as a nontraditional one-carbon (C1) unit and silylborane as an external silicon pronucleophile, a relay palladium/copper-catalyzed silylative [5 + 1] benzannulation of 3-acetoxy-1,4-enynes for producing polysubstituted arylsilanes, especially including bioactive motif-based analogues, in a single reaction step through benzene ring skeleton assembly and silyl intermolecular incorporation cascades is developed. Mechanistic studies show that this reaction allows the terminal sp-hybridized carbon atom in terminal alkynes as a C1 unit via cleavage of two π-bonds and one C(sp)-H bond.

Pd-Catalyzed Domino Imidoylation/Heck/C(sp2)-H Cyclization: Isocyanide Relay Strategy toward Tricyclic-Fused Heterocycles Containing an All-Carbon Quaternary Center.

A palladium-catalyzed domino process for the quick assembly of tricyclic-fused heterocycles starting from aryl iodides and functionalized isocyanides containing a disubstituted terminal alkene has been developed. The process is triggered by intermolecular isocyanide insertion, followed by Heck-type carbopalladation of the intramolecular alkene moiety and subsequent C(sp2)-H activation. Moreover, an asymmetric version of this reaction could also be realized in good yield with moderate enantioselectivity after preliminary exploration of chiral ligands.

[2 + 2 + 1] Heteroannulation of Alkenes with Enynyl Benziodoxolones and Silver Nitrite Involving C≡C bond Oxidative Cleavage: Entry to 3-Aryl-Δ2-isoxazolines.

A copper-catalyzed [2 + 2 + 1] heteroannulation of alkenes with enynyl benziodoxolones and AgNO2 involving oxidative cleavage of the C≡C bond promoted by cooperative Zn(OTf)2, KOAc, and 4 Å MS for producing 3-aryl Δ2-isoxazolines is reported. Mechanistic studies indicate that AgNO2 serves as the N/O two-atom unit source, enabling the formation of three bonds through NO2 addition across the C≡C bond, NO-transfer, C≡C bond cleavage, and annulation cascades.

Relationship between TP53 gene mutation and overall survival time of myelodysplastic syndromes: a Meta-analysis / 白血病·淋巴瘤

Objective:To investigate the relationship between TP53 gene mutation and overall survival (OS) time of myelodysplastic syndrome (MDS).Methods:Databases, including PubMed, Cochrane Library and Embase were searched for relevant studies published up to 20 October, 2019. The corresponding hazard ratio ( HR) and their 95% confidence interval ( CI) for OS from multivariate Cox proportional hazard models were extracted. The combined HR with their 95% CI was calculated by using fixed or random effect models. Meta-analysis was performed by using Revman 5.3 software. Results:A total of 1 033 patients from 6 studies were enrolled. Meta-analysis results showed that OS time in TP53 gene mutation group was shorter than that in wild type group for patients with MDS ( HR = 2.16, 95% CI 1.52-3.07, P < 0.01). The prognostic risk for post-transplantation patients with MDS ( HR = 2.69, 95% CI 1.63-4.43, P < 0.01) was lower compared with that for patients treated by azacitidine( HR = 2.89, 95% CI 1.37-6.08, P = 0.005). Conclusion:TP53 gene mutation is a risk factor affecting OS of MDS patients.

Relationship between TP53 gene mutation and overall survival time of myelodysplastic syndromes: a Meta-analysis / 白血病·淋巴瘤

Objective:To investigate the relationship between TP53 gene mutation and overall survival (OS) time of myelodysplastic syndrome (MDS).Methods:Databases, including PubMed, Cochrane Library and Embase were searched for relevant studies published up to 20 October, 2019. The corresponding hazard ratio ( HR) and their 95% confidence interval ( CI) for OS from multivariate Cox proportional hazard models were extracted. The combined HR with their 95% CI was calculated by using fixed or random effect models. Meta-analysis was performed by using Revman 5.3 software. Results:A total of 1 033 patients from 6 studies were enrolled. Meta-analysis results showed that OS time in TP53 gene mutation group was shorter than that in wild type group for patients with MDS ( HR = 2.16, 95% CI 1.52-3.07, P < 0.01). The prognostic risk for post-transplantation patients with MDS ( HR = 2.69, 95% CI 1.63-4.43, P < 0.01) was lower compared with that for patients treated by azacitidine( HR = 2.89, 95% CI 1.37-6.08, P = 0.005). Conclusion:TP53 gene mutation is a risk factor affecting OS of MDS patients.

Arsenic-Containing Qinghuang Powder () is an Alternative Treatment for Elderly Acute Myeloid Leukemia Patients Refusing Low-Intensity Chemotherapy / 中国结合医学杂志

OBJECTIVE@#To analyze the overall survival (OS) of elderly acute myeloid leukemia (AML) patients treated with oral arsenic-containing Qinghuang Powder (, QHP) or low-intensity chemotherapy (LIC).@*METHODS@#Forty-two elderly AML patients treated with intravenous or subcutaneous LIC (1 month for each course, at least 3 courses) or oral QHP (3 months for each course, at least 2 courses) were retrospectively analyzed from January 2015 to December 2017. The main endpoints of analysis were OS and 1-, 2-, 3-year OS rates of patients, respectively. And the adverse reactions induding bone marrow suppression, digestive tract discomfort and myocardia injury were observed.@*RESULTS@#Out of 42 elderly AML patients, 22 received LIC treatment and 20 received QHP treatment, according to patients' preference. There was no significant difference on OS between LIC and QHP patients (13.0 months vs. 13.5 months, >0.05). There was no significant difference on OS rates between LIC and QHP groups at 1 year (59.1% vs. 70.0%), 2 years (13.6% vs. 15%), and 3 years (4.6% vs. 5.0%, all >0.05). Furthermore, there was no significant difference of OS on prognosis stratification of performance status > 2 (12 months vs. 12 months), age> 75 year-old (12.0 months vs. 12.5 months), hematopoietic stem cell transplant comorbidity index >2 (12 months vs. 13 months), poor cytogenetics (12 months vs. 8 months), and diagnosis of secondary AML (10 months vs. 14 months) between LIC and QHP patients (>0.05).@*CONCLUSION@#QHP may be an alternative treatment for elderly AML patients refusing LIC therapy.

One-Carbon Incorporation Using Cyclobutanone Oxime Ester Enabled [2 + 2 + 1] Carboannulation of 1,7-Enynes by C-C/N-O Bond Cleavage and C-H Functionalization.

A NiCl2-promoted [2 + 2 + 1] carboannulation of 1,7-enynes with internally oxidative cyclobutanone oximes to produce canyo-functionalized 4H-cyclopenta[c]quinolin-4-ones is disclosed. Through C-C/N-O bond cleavage and C-H functionalization, the process enables one-carbon incorporation using cyclobutanone oximes to achieve [2 + 2 + 1] carboannulation of 1,7-enynes, which is highlighted by allowing the formation of four new bonds with high selectivity and broad substrate scope.