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1.
Chemistry ; 30(28): e202400005, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38497560

RESUMEN

New chiral targets of orientational chirality have been designed and asymmetrically synthesized by taking advantage of N-sulfinyl imine-directed nucleophilic addition/oxidation, Suzuki-Miyaura, and Sonogashira cross-coupling reactions. Orientation of single isomers has been selectively controlled by using aryl/alkynyl levers [C(sp2)-C(sp) axis] and tBuSO2- protecting group on nitrogen as proven by X-ray diffraction analysis. The key structural characteristic of resulting orientational products is shown by remote through-space blocking manner. Seventeen examples of multi-step synthesis were obtained with modest to good chemical yields and complete orientational selectivity.

2.
J Org Chem ; 89(7): 4877-4887, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38457276

RESUMEN

General and convenient visible-light-promoted alkylsulfonylation and cyanoalkylsulfonylation of MBH adducts have been developed through the multicomponent insertion of sulfur dioxide, enabling the assembly of two C-S bonds to generate structurally diverse allylic alkylsulfones (43 examples in total). The reaction of MBH adducts with potassium alkyltrifluoroborates and 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) adduct afforded sulfones with generally good yields. Notably, the addition of N,N,N',N'-tetramethylethylenediamine as a base into the photocatalytic system led to yielding an alkyl sulfonyl unit and cyano group-anchored trisubstituted alkenes by utilizing cycloketone oxime esters as C-radical precursors. Both of these reactions have constructed two C-S bonds, and all desired products were obtained in moderate to excellent yields with complete stereospecificity.

3.
Molecules ; 29(10)2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38792134

RESUMEN

In this study, the design and asymmetric synthesis of a series of chiral targets of orientational chirality were conducted by taking advantage of N-sulfinylimine-assisted nucleophilic addition and modified Sonogashira catalytic coupling systems. Orientational isomers were controlled completely using alkynyl/alkynyl levers [C(sp)-C(sp) axis] with absolute configuration assignment determined by X-ray structural analysis. The key structural element of the resulting orientational chirality is uniquely characterized by remote through-space blocking. Forty examples of multi-step synthesis were performed, with modest to good yields and excellent orientational selectivity. Several chiral orientational amino targets are attached with scaffolds of natural and medicinal products, showing potential pharmaceutical and medical applications in the future.

4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 43-48, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38433630

RESUMEN

Objective To analyze the correlations between platelet-related parameters and the incidence of anxiety and depression in the patients undergoing peritoneal dialysis(PD),and evaluate the efficacy of the parameters in the diagnosis of anxiety and depression in PD patients. Methods A total of 245 patients undergoing PD in the First Affiliated Hospital of Hebei North University from September 2022 to February 2023 were enrolled.The generalized anxiety scale(GAD-7) and the patient health questionnaire(PHQ-9) were used to evaluate the anxiety and depression of the patients,respectively.The personal information and biochemical indicators of the patients were collected,and the platelet count(PLT),mean platelet volume(MPV),and platelet distribution width(PDW) were measured.Logistic regression was adopted to analyze the relationships of platelet-related parameters with anxiety and depression in PD patients. Results Among the 245 patients undergoing PD,the incidences of anxiety and depression were 15.9% and 38.0%,respectively.There were differences in the dialysis period(Z=-2.358,P=0.018;Z=-3.079,P=0.002),MPV(Z=-4.953,P<0.001;Z=-7.878,P<0.001),and PDW(Z=-4.587,P<0.001;Z=-7.367,P<0.001) between the anxiety group and the non-anxiety group as well as between the depression group and the non-depression group.The correlation analysis showed that MPV(r=0.358,P<0.001;r=0.489,P<0.001) and PDW(r=0.340,P<0.001;r=0.447,P<0.001) were positively correlated with anxiety and depression in the patients undergoing PD.The Logistic regression model showed that MPV(P=0.022,P=0.011),PDW(P=0.041,P=0.018),and dialysis period(P=0.011,P=0.030) were independent risk factors for the anxiety and depressive state in PD patients.The areas under the receiver operating characteristic curve of MPV in the diagnosis of anxiety and depression in PD patients were 0.750 and 0.800,respectively,and those of PDW were 0.732 and 0.780,respectively. Conclusion MPV and PDW have high efficacy in the diagnosis of anxiety and depression associated with PD and can be used as objective indicators to evaluate the anxiety and depression in the patients undergoing PD.


Asunto(s)
Ansiedad , Diálisis Peritoneal , Humanos , Diálisis Peritoneal/efectos adversos , Hospitales , Modelos Logísticos , Curva ROC
5.
J Org Chem ; 88(13): 8532-8541, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37220028

RESUMEN

A new Pd(II)-catalyzed annulation/iododifluoromethylation of enynones has been developed for the synthesis of versatile 1-indanones with moderate to good yields (26 examples). The present strategy enabled the concomitant incorporation of two important difluoroalkyl and iodo functionalities into 1-indenone skeletons with (E)-stereoselectivity. The mechanistic pathway was proposed, consisting of the difluoroalkyl radical-triggered α,ß-conjugated addition/5-exo-dig cyclization/metal radical cross-coupling/reductive elimination cascade.


Asunto(s)
Indanos , Ciclización , Catálisis
6.
J Org Chem ; 88(6): 3615-3625, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36855323

RESUMEN

A catalytic site-selective ring deconstruction of cyclobuteno[a]naphthalene-4-ones with alcohols is reported, enabling the direct production of a wide range of unsymmetric 1,1-diarylated olefins with good yields and complete regioselectivity. The late-stage application of these resulting terminal olefins demonstrates great possibilities to apply this strategy to complex molecules. The protocol features good functional group compatibility, broad substrate scope, and controllable site selectivity.

7.
Neurosurg Rev ; 46(1): 305, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37982900

RESUMEN

Treatment of blood blister-like aneurysms (BBAs) of the supraclinoid internal carotid artery (ICA) with flow diverters (FDs) has become widespread in recent years. However, ruptured blood blister-like aneurysm (BBA) of ICA treatment with flow diverter-assisted coil embolization (FDAC) remains controversial. Moreover, limited direct comparative studies have been conducted between the two treatment modalities, FDs and FDAC, for BBAs. The purpose of this study was to document our experience and evaluate the effectiveness and safety of FDAC. We conducted a retrospective analysis of clinical and radiological information from ten patients who experienced ruptured BBAs of the supraclinoid ICA at our center from January 2021 to February 2023. The technical details of FDAC for ruptured BBAs were described, and the technical steps were named "pipeline embolization device (PED)-Individualized shaping(microcatheter)-Semi deploying-Rivet(coils)-Massage(microwire)" as the PEISSERM technique. Clinical outcomes were assessed using the modified Rankin Scale (mRS), whereas radiological results were determined through angiography. A pooled analysis was implemented, incorporating data from literature sources that reported perioperative and long-term clinical and angiographic outcomes of ruptured BBAs treated with FD and FDAC strategies, along with our data. Data in our analysis pool were categorized into FD and FDAC strategy groups to explore the preferred treatment modalities for BBAs. The PEISSERM technique was utilized to treat ten patients, seven males, and three females, with an average age of 41.7 years. A single PED was deployed in conjunction with coils in all ten patients. All PEDs were documented to have good wall apposition. The immediate postoperative angiograms demonstrated Raymond grade I in ten aneurysms. Angiographic follow-up of nine patients at 4-25 months showed total occlusion of the aneurysms. At the most recent follow-up, the mRS scores of nine patients hinted at a good prognosis. Pooled analysis of 233 ICA-BBA cases of FD revealed a technical success rate of 91% [95% confidence interval (CI), 0.88 to 0.95], a rate of complete occlusion of 79% (95% CI, 0.73 to 0.84), a recurrence rate of 2% (95% CI, 0.00 to 0.04), a rebleed rate of 2% (95% CI, 0.00 to 0.04), and the perioperative stroke rate was 8% (95% CI, 0.04 to 0.11). The perioperative mortality was 4% (95% CI, 0.01 to 0.07). The long-term good clinical outcome rate was 85% (95% CI, 0.80 to 0.90). The mortality rate was 6% (95% CI, 0.03 to 0.09). Results from the subgroup analysis illustrated that the FDAC strategy for BBAs had a significantly higher immediate postoperative complete occlusion rate (P < 0.001), total occlusion rate (P = 0.016), and a good outcome rate (P = 0.041) compared with the FD strategy. The FDAC strategy can yield a higher rate of good outcomes than the FD strategy. The PEISSERM technique employed by the FDAC is a reliable and effective treatment approach as it can minimize the hemodynamic burden of BBA's fragile dome, thereby achieving an excellent occlusion rate. The PEISSERM technique in the FDAC strategy contributes to understanding the BBA's treatment and offers a potentially optimal treatment for BBA.


Asunto(s)
Aneurisma Roto , Arteria Carótida Interna , Femenino , Masculino , Humanos , Adulto , Arteria Carótida Interna/cirugía , Estudios Retrospectivos , Aneurisma Roto/cirugía , Angiografía , Prótesis Vascular
8.
Chemistry ; 28(7): e202200183, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35092103

RESUMEN

Invited for the cover of this issue are Guigen Li's groups at Texas Tech University and Nanjing University. The cover artwork shows that chirality patterns exist from universal to molecular levels showing light emission properties. Read the full story of multilayer 3D chirality and its asymmetric catalytic synthesis at 10.1002/chem.202104102.


Asunto(s)
Polímeros , Catálisis , Humanos
9.
Chemistry ; 28(7): e202104102, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34962686

RESUMEN

Unprecedented chiral multilayer folding 3D polymers have been assembled and regulated by uniform and differentiated aromatic chromophore units between naphthyl piers. Screening catalysts, catalytic systems and monomers were proven to be crucial for asymmetric catalytic Suzuki-Miyaura polycouplings for this assembly. X-ray crystallography of the corresponding dimers and trimers revealed the absolute configuration and the intermolecular packing pattern. Up to 61 960 Mw /41 900 Mn and m/z 4317 for polymers and oligomers, as confirmed by gel permeation chromatography (GPC) and MALDI-TOF MS, indicated that these frameworks were composed of multiple stacked layers. The resulting multiple π-assemblies exhibited remarkable optical properties in aggregated states (photoluminescence in solids and aggregation-induced emission in solutions), as well as reversible redox properties in electrochemical performance.


Asunto(s)
Polímeros , Catálisis , Cromatografía en Gel , Cristalografía por Rayos X
10.
J Org Chem ; 87(9): 5976-5986, 2022 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-35442684

RESUMEN

Asymmetric synthesis of new atropisomerically multilayered chiral targets has been achieved by taking advantage of the strategy of center-to-multilayer chirality and double Suzuki-Miyaura couplings. Diastereomers were readily separated via flash column chromatography and well characterized. Absolute configuration assignment was determined by X-ray structural analysis. Five enantiomerically pure isomers possessing multilayer chirality were assembled utilizing anchors involving electron-rich aromatic connections. An overall yield of 0.69% of the final target with hydroxyl attachment was achieved over 11 steps from commercially available starting materials.


Asunto(s)
Electrones , Estereoisomerismo
11.
Zhonghua Nan Ke Xue ; 28(8): 696-701, 2022 Aug.
Artículo en Zh | MEDLINE | ID: mdl-37838968

RESUMEN

OBJECTIVE: At present, the longest network transmission distance (NTD) for 5G remote endoscopic surgery is reportedly only about 229 km, and the NTD longer than 5 000 km has not yet been reported in clinical application. In this study, we attempted the clinical application of 5G ultra-remote robot-assisted laparoscopic surgery in spermatic vein ligation. METHODS: This retrospective study included two cases of 5G ultra-remote robot-assisted laparoscopic spermatic vein ligation using the home-made Tumai Surgical Robot System. The operation table was located in Xinjiang Kezhou People's Hospital, with an NTD of about 5 800 km (a linear distance of about 3 800 km) from the surgeon's console in the Telemedical Center of the First Affiliated Hospital of Nanjing Medical University, the apparatuses connected through the public 5G network. We observed the network connection delay, network fluctuation, and data packet loss rate of the devices at both ends of the loop through the feedback value of the Ping command by real-time monitoring. RESULTS: The total operation time of the two cases was 45 and 40 minutes respectively, with a mean blood loss of < 5 ml. The patients resumed a liquid diet and out-of-bed activity on the first day, the abdominal drainage tubes removed on the second, and both discharged from the hospital on the third day. The intraoperative average two-way network delay was 130 ms, and the average continuous data packet loss rate was 1.4%. No adverse network events, such as network interruption, occurred during the operation. CONCLUSION: Through the public 5G network and home-made Tumai Surgical Robot System, ultra-remote robot-assisted laparoscopic surgery was performed safely and successfully.


Asunto(s)
Laparoscopía , Procedimientos Quirúrgicos Robotizados , Robótica , Varicocele , Masculino , Humanos , Varicocele/cirugía , Varicocele/etiología , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Resultado del Tratamiento
12.
J Org Chem ; 85(11): 7036-7044, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32383594

RESUMEN

A new single Pd-catalyzed decarboxylative allylation-nucleophilic cyclization relay is reported by using α-alkynyl arylols and vinylethylene carbonates (or vinyl carbamates), and a wide range of 3-allyl benzofurans with generally good yields were stereoselectively synthesized under mild conditions, among which the complete stereoselectivity of some cases was also observed. Notably, the present catalysts can tolerate air conditions without any ligand, additive, or base, opening new avenues to build up oxa-heterocycle frameworks through catalytic difunctionalization of internal alkynes.

13.
Chemistry ; 25(11): 2750-2756, 2019 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-30536452

RESUMEN

Developing highly luminescent and extensively stable silver cluster-assembled materials (SCAMs) from the inferior luminogens and unstable silver cluster is an important and challenging issue. Herein, a new luminescent three-dimensional SCAM (Ag12 CPPP, [Ag12 (StBu)6 (CF3 COO)6 (CPPP)2 (DMAc)12 ]n ; CPPP=2,5-bis(4-cyanophenyl)-1,4-bis(4-(pyridine-4-yl)-phenyl)-1,4-dihydropyrrolo[3,2-b]pyrrole, DMAc=dimethylacetamide) was designed and synthesized with a quadridentate rigid emission ligand (CPPP) and a silver-chalcogenolate cluster (SCC) containing 12 AgI atoms. The luminescence study indicates that CPPP is an aggregation-caused quenching (ACQ) molecule with twisted intramolecular charge transfer (TICT) character. Benefiting from the strong immobilization effect in the robust framework, the quantum yield of CPPP is greatly enhanced in Ag12 CPPP compared with that of CPPP in solution or in the solid state. As a result, Ag12 CPPP exhibits typical matrix coordination induced emission (MCIE) effect. Such efficient rigidifying methodology provides a promising approach for enhancing luminescence of ACQ molecules in an aggregated state and strengthening the silver cluster in an unstable state.

14.
Chemistry ; 25(13): 3376-3381, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30633396

RESUMEN

Silver chalcogenolate clusters (SCCs) and silver cluster-assembled materials (SCAMs) are an important category of novel luminescent materials, the emission of which can be modulated by variation of the cluster nodes and linker species. Here, the successfully synthesis of two isostructural 2D SCAMs is reported: Ag12 bpa and Ag12 bpe are formed by using two linkers with different conformational freedom (bpa=1,2-bis(4-pyridyl)ethane, bpe=1,2-bis(4-pyridyl)ethylene), with dodenuclear silver chalcogenolate clusters as secondary building units (SBUs). Interestingly, nonluminescent Ag12 bpa at room temperature could quickly transform into 1D Ag10 bpa, with concomitant dissociation of two silver atoms and the remaining ten silver atoms rearranging in the cluster, thus exhibiting an intense yellow phosphorescence after being triggered by acetonitrile (CH3 CN). Similarly, stimulating Ag12 bpe with CH3 CN, by contrast, gave another 2D structure Ag12 bpe-1b with the distorted SBUs and different topology structure, and both of them are merely red-emissive at low temperature. To note, after exchanging ligands, room-temperature nonluminescent 2D Ag12 bpe-1b can be transformed into intensely luminescent 1D Ag10 bpa. This linker-flexibility-dependent structural transformation and cluster-based SBU controlled luminescence remains scarce. Our work provides new insights into structure-luminescence relationship in clustered metal-organic frameworks and intelligent stimulus-responsive luminescent materials.

15.
Int Heart J ; 60(2): 419-428, 2019 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-30745541

RESUMEN

The role of autophagy in the cardioprotection conferred by ischemic preconditioning (IPC) has been well described. This study aimed to investigate the changes in autophagy levels during the cardioprotective effects initiated by exercise preconditioning (EP).Rats were randomly divided into 4 groups: group C (control), group EP, group EE (exhaustive exercise), and group EP + EE (EP pretreatment at 0.5 hours before EE). The EP protocol included 4 periods of 10 minutes of treadmill running each at 30 m/minute with intervening 10 minute periods of rest. Hematoxylin-basic fuchsin-picric acid (HBFP) staining and plasma levels of cardiac troponin I (cTnI) were used to evaluate the ischemia-hypoxia injury in rat myocardium. Alteration levels in several autophagy proteins in the left ventricular myocardium were analyzed by Western blot. The phasic alterations of autophagy levels during EP-initiated cardioprotective phase were also examined.Compared with group C, the ischemia-hypoxia positive areas and IOD value in HBFP-staining and cTnI plasma levels increased significantly in group EE. Compared with group EE, the ischemia-hypoxia injury was markedly attenuated in group EP + EE. Compared with group C, the LC3-II/LC3-I ratio, a marker of autophagosome formation, was reduced in group EE, but the LC3-II/LC3-I ratio remained unaltered in group EP + EE. Furthermore, the LC3-II/LC3-I ratio increased significantly at 2 hours during the cardioprotective phase after EP.These results suggest that the activated autophagy level during the EP-initiated cardioprotective phase may be partly involved in the cardioprotective effects by maintaining a normal autophagy basal level during the subsequent exhaustive exercise in rat myocardium.


Asunto(s)
Autofagia/fisiología , Precondicionamiento Isquémico Miocárdico/métodos , Proteínas Asociadas a Microtúbulos/metabolismo , Isquemia Miocárdica , Miocardio/metabolismo , Condicionamiento Físico Animal/fisiología , Animales , Autofagosomas/metabolismo , Vasos Coronarios , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatología , Isquemia Miocárdica/prevención & control , Ratas , Ratas Sprague-Dawley , Troponina I/sangre
16.
J Am Chem Soc ; 140(2): 594-597, 2018 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-29281275

RESUMEN

To realize the molecular design of new functional silver(I) clusters, a new synthetic approach has been proposed, by which the weakly coordinating ligands NO3- in a Ag20 thiolate cluster precursor can be substituted by carboxylic ligands while keeping its inner core intact. By rational design, novel atom-precise carboxylic or amino acid protected 20-core Ag(I)-thiolate clusters have been demonstrated for the first time. The fluorescence and electrochemical activity of the postmodified Ag20 clusters can be modulated by alrestatin or ferrocenecarboxylic acid substitution. More strikingly, when chiral amino acids were used as postmodified ligands, CD-activity was observed for the Ag20 clusters, unveiling an efficient way to obtain atom-precise chiral silver(I) clusters.

17.
Org Biomol Chem ; 16(39): 7104-7108, 2018 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-30234224

RESUMEN

A first atom-economic [2 + 2] cycloaddition/1,6-conjugate addition cascade of yne-allenones with C-nucleophiles including 1,3-dicarbonyls and α,α-dicyanoolefins under base-promoted conditions has been established, enabling the direct construction of C(sp3)-C(sp3) bonds to generate cyclobuta[a]naphthalen-1-ols with generally good yields. These resulting products have a cyclobutene unit that contains both an aryl and alkyl group.

19.
Angew Chem Int Ed Engl ; 56(49): 15570-15574, 2017 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-28913917

RESUMEN

A metal-free [2+2] cycloaddition and 1,4-addition sequence induced by S-centered radicals has been achieved by treating benzene-linked allene-ynes with aryldiazonium tetrafluoroborates and DABCO-bis(sulfur dioxide) in a one-pot procedure. The reaction provides a greener and more practical access to functionalized cyclobuta[a]naphthalen-4-ols with valuable applications. More than 50 examples are demonstrated with excellent diastereoselectivity and chemical yields. The reaction pathway is proposed to proceed by the following steps:[2+2] cycloaddition, insertion of SO2 , 1,4-addition, diazotization, and tautomerization.

20.
Front Chem ; 12: 1371978, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38595704

RESUMEN

The first photocatalytic trichloromethyl radical-triggered annulative reactions of amide-linked 1,7-diynes with polyhalomethanes were established for the flexible assembly of functionalized quinolin-2(1H)-ones with generally acceptable yields. With the installation of the aryl group (R1) into the alkynyl moiety, C-center radical-initiated Kharasch-type addition/nucleophilic substitution/elimination cascade to produce quinolin-2(1H)-ones-incorporating gem-dihaloalkene, whereas three examples of polyhalogenated quinolin-2(1H)-ones were afforded when amide-linked 1,7-diynes bearing two terminal alkyne units were subjected to BrCX3 by exploiting dry acetonitrile as a solvent.

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