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1.
Heliyon ; 10(12): e32391, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38975114

ABSTRACT

Background: Postoperative hypothermia (POH) is a common issue in colorectal surgery patients, leading to complications. This study aimed to develop and validate a predictive model for identifying POH in colorectal surgery patients. Methods: A retrospective analysis of 1,316 patients who underwent colorectal surgery between June 2020 and September 2022 was conducted using institutional medical records. Intraoperative core temperatures and potential influencing factors were collected, and regression analysis was used to identify risk factors for POH and create a model. The model's performance was evaluated using the receiver operating characteristic curve analysis. Results: Intraoperative hypothermia occurred in 51.5 % of patients. Significant predictors of POH included gender, alcohol consumption, surgery duration, platelet count, and age. The constructed model included factors like fluid intake, platelets, cigarette use, alcohol consumption, surgery type, muscle relaxants, age, ABSI, and gender. The model showed good predictive performance with an area under the ROC curve of 0.981 and a Hosmer-Lemeshow test p-value of 0.676. The Youden index, sensitivity, specificity, and practical application rate were 0.602, 0.790, 0.812, and 98.81 %, respectively. Conclusion: This study developed a predictive model for POH in colorectal surgery patients, considering individual factors and exploring underlying causes. Understanding risk factors and consequences of POH is crucial for nurses and perioperative professionals in clinical practice.

2.
Org Biomol Chem ; 22(16): 3204-3208, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38563260

ABSTRACT

An efficient palladium-catalyzed [2 + 2 + 1] annulation of 3-iodochromones, bridged olefins, and iodomethane is described, affording a range of chromone-containing polycyclic compounds. Additionally, the corresponding deuterated products were smoothly obtained with iodomethane-d3 instead of iodomethane. Moreover, the synthetic utility of this method is further substantiated by gram scale preparation and application to late-stage modification of estrone.

3.
Angew Chem Int Ed Engl ; 63(13): e202318887, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38237082

ABSTRACT

Trifluoromethyl cationic carbyne (CF3 C+ :) possessing dual carbene-carbocation behavior emulated as trifluoromethyl metal-carbynoid (CF3 C+ =M) has not been explored yet, and its reaction characteristics are unknown. Herein, a novel α-diazotrifluoroethyl sulfonium salt was prepared and used in Rh-catalyzed three-component [2+1+2] cycloadditions for the first time with commercially available N-fused heteroarenes and nitriles, yielding a series of imidazo[1,5-a] N-heterocycles that are of interest in medicinal chemistry, in which the insertion of trifluoromethyl Rh-carbynoid (CF3 C+ =Rh) into C=N bonds of N-fused heteroarenes was involved. This strategy demonstrates synthetic applications in late-stage modification of pharmaceuticals, construction of CD3 -containing N-heterocycles, gram-scale experiments, and synthesis of phosphodiesterase 10A inhibitor analog. These highly valuable and modifiable imidazo[1,5-a] N-heterocycles exhibit good antitumor activity in vitro, thus demonstrating their potential applications in medicinal chemistry.

4.
Org Lett ; 25(27): 5049-5054, 2023 07 14.
Article in English | MEDLINE | ID: mdl-37405417

ABSTRACT

A biocatalytic approach for the synthesis of metaxalone and its analogues was developed based on the reaction of epoxides and cyanate catalyzed by halohydrin dehalogenase. Gram-scale synthesis of chiral and racemic metaxalone was achieved with 44% (98% ee) and 81% yields, respectively, by protein engineering of the halohydrin dehalogenase HHDHamb from Acidimicrobiia bacterium. Additionally, various metaxalone analogues were synthesized at 28-40% yields (90-99% ee) for chiral forms and 77-92% yields for racemic forms.


Subject(s)
Oxazolidinones , Protein Engineering , Biocatalysis , Bacteria
5.
Risk Manag Healthc Policy ; 16: 921-930, 2023.
Article in English | MEDLINE | ID: mdl-37223427

ABSTRACT

Objective: To analyze the epidemiological data of patients with septic cardiomyopathy and investigate the relationship between ultrasonic parameters and prognosis of patients with sepsis. Methods: In this study, we enrolled patients with sepsis who were treated at the Department of Critical Care Medicine in the Beijing Electric Power Hospital (No.1 Taipingqiao Xili, Fengtai District, Beijing) from January 2020 to June 2022. All patients received standardized treatment. Their general medical status and 28-day prognosis were recorded. Transthoracic echocardiography was performed within 24 hours after admission. We compared the ultrasound indexes between the mortality group and the survival group at the end of 28 days. We included parameters with significant difference in the logistic regression model to identify the independent risk factors for prognosis and evaluated their predictive value using receiver operating characteristic (ROC) curve. Results: We included 100 patients with sepsis in this study; the mortality rate was 33% and the prevalence rate of septic cardiomyopathy was 49%. The peak e' velocity and right ventricular systolic tricuspid annulus velocity (RV-Sm) of the survival group were significantly higher than those of the mortality group (P < 0.05). Results of logistic regression analysis showed that the peak e' velocity and RV-Sm were independent risk factors for prognosis. The area under curve of the peak e' velocity and the RV-Sm was 0.657 and 0.668, respectively (P < 0.05). Conclusion: The prevalence rate of septic cardiomyopathy in septic patients is high. In this study, we found that the peak e' velocity and right ventricular systolic tricuspid annulus velocity were important predictors of short-term prognosis.

6.
J Org Chem ; 88(1): 371-383, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36563325

ABSTRACT

A cooperative tertiary amine/palladium-catalyzed sequential reaction process, proceeding via a [4 + 3] cyclization of isatin-derived Morita-Baylis-Hillman Expansion (MBH) carbonates and tert-butyl 2-(hydroxymethyl)allyl carbonates followed by a [1,3]-rearrangement, has been found and developed. A range of structurally diverse spiro[methylene cyclopentane-1,3'-oxindolines] bearing two adjacent ß,γ-acyl quaternary carbon stereocenters, which are difficult to obtain by conventional strategies, were obtained in good yields. Further synthetic utility of this protocol is highlighted by its excellent regio- and stereocontrol as well as the large-scale synthesis and diverse functional transformations of the synthetic compounds. Moreover, the control experiments probably established the plausible mechanism for this sequential [4 + 3] cyclization/[1,3]-rearrangement process.


Subject(s)
Carbonates , Palladium , Cyclization , Molecular Structure , Stereoisomerism , Catalysis , Amines
7.
Org Lett ; 24(51): 9392-9397, 2022 12 30.
Article in English | MEDLINE | ID: mdl-36524990

ABSTRACT

Reported herein is a novel palladium-catalyzed [2 + 2 + 1] domino annulation of 3-iodochromones, bridged olefins, and dimethyl squarate allowing the construction of chromone-containing polycyclic compounds in good to high yields. Importantly, dimethyl squarate is first employed as the solid C1 source in organic synthesis. Gram-scale experiments, late-stage modification of natural products, as well as transformations of products show potential for further synthetic elaborations.


Subject(s)
Palladium , Polycyclic Compounds , Chromones , Catalysis , Norbornanes
8.
Angew Chem Int Ed Engl ; 61(52): e202212589, 2022 12 23.
Article in English | MEDLINE | ID: mdl-36328962

ABSTRACT

Expanding the enzymatic toolbox for the green synthesis of valuable molecules is still of high interest in synthetic chemistry and the pharmaceutical industry. Chiral thiiranes are valuable sulfur-containing heterocyclic compounds, but relevant methods for their enantioselective synthesis are limited. Herein, we report a biocatalytic thionation strategy for the enantioselective synthesis of thiiranes, which was developed based on the halohydrin dehalogenase (HHDH)-catalyzed enantioselective ring-opening reaction of epoxides with thiocyanate and a subsequent nonenzymatic rearrangement process. A novel HHDH was identified and engineered for enantioselective biocatalytic thionation of various aryl- and alkyl-substituted epoxides on a preparative scale, affording the corresponding thiiranes in up to 43 % isolated yield and 98 % ee. Large-scale synthesis and useful transformations of chiral thiiranes were also performed to demonstrate the utility and scalability of the biocatalytic thionation strategy.


Subject(s)
Epoxy Compounds , Epoxy Compounds/chemistry , Stereoisomerism , Biocatalysis
9.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 34(7): 740-745, 2022 Jul.
Article in Chinese | MEDLINE | ID: mdl-36100414

ABSTRACT

OBJECTIVE: To investigate the epidemiological characteristics of septic cardiomyopathy and explore the relationship between the relevant indexes measured by echocardiography and the prognosis of patients with sepsis. METHODS: A case-control study was conducted. The data of patients with sepsis admitted to the department of critical care medicine of Jiangsu Subei People's Hospital Affiliated to Yangzhou University and the department of critical care medicine of Beijing Electric Power Hospital of State Grid Corporation of China from June 2018 to June 2021 were enrolled. The general information and 28-day prognosis were recorded. At the same time, ultrasonic parameters obtained by transthoracic echocardiography within 24 hours after intensive care unit (ICU) admission were recorded. The differences in ultrasound indexes between the death group and the survival group on 28 days were compared. Parameters with significant statistical differences between the death group and the survival group were included in the Logistic regression analysis to find the independent risk factors for the prognosis of patients with sepsis, the predictive value of each index for the prognosis of patients with sepsis was evaluated by receiver operator characteristic curve (ROC curve). RESULTS: A total of 145 patients with sepsis were enrolled, including 106 patients with septic shock. Among the 145 patients, septic cardiomyopathy was found in 73 patients, with the incidence of 50.3%. The incidence of left ventricular diastolic dysfunction cardiomyopathy was 41.4% (n = 60), the incidence of left ventricular systolic dysfunction cardiomyopathy was 24.8% (n = 36), and the incidence of right ventricular systolic dysfunction cardiomyopathy was 12.4% (n = 18). At 28 days, 98 patients survived and 47 died, with the mortality of 32.4%. The peak e' velocity by tissue Doppler imaging (e') and right ventricular myocardial systolic tricuspid annulus velocity (RV-Sm) of the death group were significantly lower than those of the survival group [e' (cm/s): 7.81±1.12 vs. 8.61±1.02, RV-Sm (cm/s): 12.12±2.04 vs. 13.73±1.74, both P < 0.05], left ventricular ejection fraction (LVEF) and left ventricular systolic mitral annulus velocity (LV-Sm) in the death group were slightly higher than those in the survival group [LVEF: 0.550±0.042 vs. 0.548±0.060, LV-Sm (cm/s): 8.92±2.11 vs. 8.23±1.71], without significant differences (both P > 0.05). Parameters with significant statistical differences between the two groups were included in the Logistic regression analysis and showed that e' and RV-Sm were independent risk factors for the 28-day prognosis of patients with sepsis [e': odds ratio (OR) = 0.623, 95% confidence interval (95%CI) was 0.410-0.947, P = 0.027; RV-Sm: OR = 0.693, 95%CI was 0.525-0.914, P = 0.010]. ROC curve analysis showed that the area under the ROC curve (AUC) of e' for predicting the 28-day prognosis of patients with sepsis was 0.657, 95%CI was 0.532-0.781, P = 0.016, the best cut-off value was 8.65 cm/s, the sensitivity was 62.1%, and the specificity was 73.4%. The AUC of RV-Sm for predicting the 28-day prognosis of patients with sepsis was 0.641, 95%CI was 0.522-0.759, P = 0.030, the best cut-off value was 14.80 cm/s, the sensitivity was 96.6%, and the specificity was 26.6%. CONCLUSIONS: The incidence of septic cardiomyopathy is high. The LVEF measured by early echocardiography has no predictive value for 28-day prognosis in septic patients, while RV-Sm and e' are important predictors for 28-day prognosis.


Subject(s)
Cardiomyopathies , Sepsis , Ventricular Dysfunction, Left , Cardiomyopathies/diagnostic imaging , Case-Control Studies , Echocardiography/methods , Humans , Prognosis , Stroke Volume , Ventricular Function, Left
10.
Org Lett ; 24(22): 4052-4057, 2022 Jun 10.
Article in English | MEDLINE | ID: mdl-35622347

ABSTRACT

With a Cu(OTf)2/chiral ferrocenyl P,N-ligand complex as a catalyst, the enantioselective desymmetrization of N-arylmaleimides was successfully realized by taking advantage of the asymmetric 1,3-dipolar cycloaddition reaction of N-2,2,2-trifluoroethylisatin ketimines. A series of structurally diverse F3C-containing octahydropyrrolo[3,4-c]pyrroles, bearing four contiguous carbon stereocenters and one stereogenic chiral C-N axial bond, were obtained with excellent results (≤99% yield, >20:1 dr, and 99% ee).

11.
J Org Chem ; 87(6): 4112-4123, 2022 03 18.
Article in English | MEDLINE | ID: mdl-35258307

ABSTRACT

An inexpensive copper-catalyzed sequential reaction process, proceeding via a nucleophilic attack of amine to Cu-carbene generated in situ from heterocyclic N-tosylhydrazone precursors followed by a 1,2-H shift/oxidative cyclization cascade of N-ylides, has been described, smoothly generating the corresponding structurally various spiro-dihydropyrrolo[1,2-a]quinoxaline derivatives. Furthermore, the significance of this protocol can be also highlighted by its diverse conversions of the synthetic compounds to the potentially bioactive molecules such as the 2-substituted pyrrolo[1,2-a]quinoxalins.


Subject(s)
Copper , Quinoxalines , Aniline Compounds , Catalysis , Cyclization , Molecular Structure
12.
Org Lett ; 23(23): 9256-9261, 2021 12 03.
Article in English | MEDLINE | ID: mdl-34802247

ABSTRACT

We present herein a visible-light-induced [3 + 2] cycloaddition of a hypervalent iodine(III) reagent with α-ketoacids for the construction of 5-CF3-1,3,4-oxadiazoles that are of importance in medicinal chemistry. The reaction proceeds smoothly without a photocatalyst, metal, or additive under mild conditions. Different from the well-established trifluorodiazoethane (CF3CHN2), the diazotrifluoroethyl radical [CF3C(·)N2], a trifluoroethylcarbyne (CF3CC:) equivalent and an unusual CF3-containing building block, is involved in the present reaction system.

13.
iScience ; 24(8): 102883, 2021 Aug 20.
Article in English | MEDLINE | ID: mdl-34401667

ABSTRACT

Asymmetric functionalization of alkenes allows the direct synthesis of a wide range of chiral compounds. Vicinal hydroxyazidation of alkenes provides a desirable path to 1,2-azidoalcohols; however, existing methods are limited by the control of stereoselectivity and regioselectivity. Herein, we describe a dual-enzyme cascade strategy for regiodivergent and stereoselective hydroxyazidation of alkenes, affording various enantiomerically pure 1,2-azidoalcohols. The biocatalytic cascade process is designed by combining styrene monooxygenase-catalyzed asymmetric epoxidation of alkenes and halohydrin dehalogenase-catalyzed regioselective ring opening of epoxides with azide. Additionally, a one-pot chemo-enzymatic route to chiral ß-hydroxytriazoles from alkenes is developed via combining the biocatalytic cascades and Cu-catalyzed azide-alkyne cycloaddition.

14.
Org Biomol Chem ; 19(21): 4720-4725, 2021 06 02.
Article in English | MEDLINE | ID: mdl-33969846

ABSTRACT

An organometal catalytic conversion of 3-aminooxindoles for the diastereo- and enantioselective synthesis of homoallylic aminooxindoles has been described. The asymmetric allylic alkylation of 3-aminooxindoles with allyl carboxylates proceeded smoothly to afford a series of chiral 3-allyl-3-aminooxindoles. This work offers an alternative route to build these scaffolds. The application of this protocol is also highlighted by a significant conversion of products to the potential applicable spiro[indoline-3,2'-pyrrolidin]-2-one derivatives.

15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(3): 327-330, 2020 Jun 30.
Article in Chinese | MEDLINE | ID: mdl-32616127

ABSTRACT

Objective To investigate cerebral autoregulation(CA)in patients with severe unilateral carotid artery stenosis by near infrared spectroscopy. Methods Thirty patients who underwent general anesthesia in our hospital from January 2015 to February 2017 were enrolled in this study.The stenosis group included 15 patients with severe unilateral internal carotid artery stenosis,and the control group included 15 patients without carotid artery stenosis.Both groups were matched in sex and age.Cerebral tissue oxygenation index(TOI)and mean arterial pressure were recorded continuously under stable general anesthesia.The Pearson correlation coefficient(r)was calculated to judge the CA status. Results TOI was not significantly different between the stenosis side and the non-stenosis side in the stenosis group(66.52±6.50 vs. 65.23±4.50;t=0.93, P=0.368)or between the stenosis side in the stenosis group and the stenosis side in the control group(66.52±6.50 vs. 64.22±3.87;t=1.18, P=0.248).The r values of stenosis side and non-stenosis side in the stenosis group were 0.36±0.12 and 0.17±0.11,respectively,and the r values of the stenosis side in the stenosis group and the stenosis side of the control group were 0.36±0.12 and 0.13±0.08,respectively.In the stenosis group,5 patients had transient ischemic attack and 2 patients had a history of stroke within 3 months before operation.When an r value of 0.342 was used as the judgment point of CA abnormality,the sensitivity and specificity were 0.625 and 0.909,respectively. Conclusion Within the range of normal blood pressure fluctuation,cerebral blood flow is linked to blood pressure at the stenosis side in patients with severe unilateral carotid artery stenosis.


Subject(s)
Carotid Stenosis , Ischemic Attack, Transient , Blood Pressure , Cerebrovascular Circulation , Homeostasis , Humans
16.
Chembiochem ; 21(13): 1820-1825, 2020 07 01.
Article in English | MEDLINE | ID: mdl-32012422

ABSTRACT

A self-sufficient cytochrome P450 monooxygenase from Deinococcus apachensis (P450DA) was identified and successfully overexpressed in Escherichia coli BL21(DE3). P450DA would be a member of the CYP102D subfamily and assigned as CYP102D2 according to the phylogenetic tree and sequence alignment. Purification and characterization of the recombinant P450DA indicated both NADH and NADPH could be used by P450DA as a reducing cofactor. The recombinant E. coli (P450DA) strain was functionally active, showing excellent enantioselectivity for benzylic hydroxylation of methyl 2-phenylacetate. Further substrate scope studies revealed that P450DA is able to catalyze benzylic hydroxylation of a variety of compounds, affording the corresponding chiral benzylic alcohols in 86-99 % ee and 130-1020 total turnover numbers.


Subject(s)
Bacterial Proteins/metabolism , Benzyl Alcohol/metabolism , Cytochrome P-450 Enzyme System/metabolism , Deinococcus/metabolism , Amino Acid Sequence , Bacterial Proteins/classification , Bacterial Proteins/genetics , Benzyl Alcohol/chemistry , Biocatalysis , Cytochrome P-450 Enzyme System/classification , Cytochrome P-450 Enzyme System/genetics , Escherichia coli/metabolism , Hydroxylation , NADP/chemistry , NADP/metabolism , Phylogeny , Recombinant Proteins/biosynthesis , Recombinant Proteins/metabolism , Sequence Alignment , Stereoisomerism , Substrate Specificity
17.
Org Biomol Chem ; 18(6): 1112-1116, 2020 02 14.
Article in English | MEDLINE | ID: mdl-31984976

ABSTRACT

A palladium-catalyzed [2 + 2 + 1] domino annulation of 3-iodochromones, α-bromo carbonyl compounds, and tetracyclododecene (TCD) is described. This approach provides a facile, efficient and atom-economical route to a variety of chromone-containing polycyclic compounds bearing fused/bridged-ring systems in good yields (up to 81%) with excellent diastereoselectivities (99 : 1 dr in all cases).

18.
Org Lett ; 21(21): 8751-8755, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31642680

ABSTRACT

A new method for the ex situ generation of difluorodiazoethane (CF2HCHN2) and a procedure for its efficient use in [3 + 2] cycloaddition with nitroolefins by the AcOH/O2 catalyst system were developed by using a simple two-chamber system. The method provides a facile and straightforward access to a series of 4-substituted 5-difluoromethyl-3-nitro-1H-pyrazoles that are of interest in medicinal chemistry. Interestingly, the key factor for the success of this method is the efficient preparation of CF2HCHN2 by an ex situ process.

19.
Org Lett ; 21(21): 8857-8860, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31638817

ABSTRACT

A palladium-catalyzed three-component [2 + 3 + 1] domino annulation among 3-iodochromones, α-bromoacetophenones, and norbornene is presented, affording various chromone-containing polycyclic compounds bearing fused/spiro/bridged-ring systems. For the first time, the 2,2-bifunctionalization of norbornene was realized in palladium-catalyzed domino reaction. This cyclization characterizes three new bonds (two C-C and one C-O) in a single operation and produces nontrivial spiro-norbornane fragments in comparison with a traditional palladium-catalyzed process involving norbornene.

20.
Org Biomol Chem ; 17(29): 6998-7001, 2019 07 24.
Article in English | MEDLINE | ID: mdl-31304944

ABSTRACT

A novel and efficient Cu(i)-catalyzed homo-coupling of indanone derivatives using diaziridinone as an oxidant is described. A variety of 1,4-dicarbonyl compounds bearing two adjacent quaternary stereocenters were obtained in high yields with high diastereoselectivities via a base-free and operationally simple process under mild reaction conditions.


Subject(s)
Aziridines/chemistry , Coordination Complexes/chemistry , Copper/chemistry , Indans/chemical synthesis , Catalysis , Indans/chemistry , Molecular Structure , Stereoisomerism
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