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Two-dimensional (2D) organic-inorganic metal halide perovskites have gained immense attention as alternatives to three-dimensional (3D) perovskites in recent years. The hydrophobic spacers in the layered structure of 2D perovskites make them more moisture-resistant than 3D perovskites. Moreover, they exhibit unique anisotropic electrical transport properties due to a structural confinement effect. In this study, four lead-free Dion-Jacobson (DJ) Sn-based phase perovskite single crystals, 3AMPSnI4, 4AMPSnI4, 3AMPYSnI4, and 4AMPYSnI4 [AMP = (aminomethyl)-piperidinium, AMPY = (aminomethyl)pyridinium] are reported. Results reveal structural differences between them impacting the resulting optical properties. Namely, higher octahedron distortion results in a higher absorption edge. Density functional theory (DFT) is also performed to determine the trends in energy band diagrams, exciton binding energies, and formation energies due to structural differences among the four single crystals. Finally, a field-effect transistor (FET) based on 4AMPSnI4 is demonstrated with a respectable hole mobility of 0.57 cm2 V-1 s-1 requiring a low threshold voltage of only -2.5 V at a drain voltage of -40 V. To the best of our knowledge, this is the third DJ-phase perovskite FET reported to date.
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Tin (Sn)-based perovskites are being investigated in many optoelectronic applications given their similar valence electron configuration to that of lead-based perovskites and the potential environmental hazards of lead-based perovskites. However, the formation of high-quality Sn-based perovskite films faces several challenges, mainly due to the easy oxidation of Sn2+ to Sn4+ and the fast crystallization rate. Here, to develop an environmentally friendly process for Sn-based perovskite fabrication, a series of natural antioxidants are studied as additives and ascorbic acid (VitC) is found to have a superior ability to inhibit the oxidation problem. A common cyclic molecule, 18-Crown-6, is further added as a second additive, which synergizes with VitC to significantly reduce the nonradiative recombination pathways in the PEA2SnI4 film. This synergistic effect greatly improves the performance of 2D red Sn-based PeLED, with a maximum external quantum efficiency of 1.87% (≈9 times that of the pristine device), a purer color, and better bias stability. This work demonstrates the potential of the dual-additive approach in enhancing the performance of 2D Sn-based PeLEDs, while the use of these environmentally friendly additives contributes to their future sustainability.
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Two-dimensional (2D) tin (Sn)-based perovskites have recently received increasing research attention for perovskite transistor application. Although some progress is made, Sn-based perovskites have long suffered from easy oxidation from Sn2+ to Sn4+ , leading to undesirable p-doping and instability. In this study, it is demonstrated that surface passivation by phenethylammonium iodide (PEAI) and 4-fluorophenethylammonium iodide (FPEAI) effectively passivates surface defects in 2D phenethylammonium tin iodide (PEA2 SnI4 ) films, increases the grain size by surface recrystallization, and p-dopes the PEA2 SnI4 film to form a better energy-level alignment with the electrodes and promote charge transport properties. As a result, the passivated devices exhibit better ambient and gate bias stability, improved photo-response, and higher mobility, for example, 2.96 cm2 V-1 s-1 for the FPEAI-passivated films-four times higher than the control film (0.76 cm2 V-1 s-1 ). In addition, these perovskite transistors display non-volatile photomemory characteristics and are used as perovskite-transistor-based memories. Although the reduction of surface defects in perovskite films results in reduced charge retention time due to lower trap density, these passivated devices with better photoresponse and air stability show promise for future photomemory applications.
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In this study, we prepared three benzo[ghi]perylenetriimide (BPTI) conjugated molecules as electron-transporting surface-modifying layers for polymer solar cells (PSCs). These three BPTI derivatives differed in the nature of their terminal functionalities, featuring butylamine (C3NH2), propylammonium iodide (C3NH3I), and butyldimethylamine (C3DMA) units, respectively. We evaluated the optoelectronic properties of PTB7-Th: PC71BM blends modified with these interfacial layers, as well as the performance of resulting PSCs. We used UV-Vis spectroscopy, atomic force microscopy, surface energy analysis, ultraviolet photoelectron spectroscopy, and photoelectric flow measurements to examine the phenomena behind the changes in the optoelectronic behavior of these blend films. The presence of a BPTI derivative changed the energy band alignment at the ZnO-active layer interface, leading to the ZnO film behaving more efficiently as an electron-extraction electrode. Modifying the ZnO surface with the BPTI-C3NH3I derivative resulted in a best power conversion efficiency (PCE) of 10.2 ± 0.53% for the PTB7-Th:PC71BM PSC (cf. PCE of the control device of 9.1 ± 0.13%). In addition, modification of a PM6:Y6:PCBM PSC with the BPTI-C3NH3I derivative increased its PCE from 15.6 ± 0.25% to 16.5 ± 0.18%. Thus, BPTI derivatives appear to have potential as IFLs when developing high-performance PSCs, and might also be applicable in other optoelectronic devices.
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In this study, a highly sensitive trilayer photodetector using Co-doped ZnFe2O4 thin films annealed at 400 °C was synthesized successfully. Trilayer-photodetector devices with a film stack of 5 at % Co-doped-zinc-ferrite-thin-film/indium-tin-oxide on p+-Si substrates were fabricated by radio-frequency sputtering. The absorbance spectra, photoluminescence spectra, transmission electron microscopy images, and I-V characteristics under various conditions were comprehensively investigated. The outstanding performance of trilayer-photodector devices was measured, including a high photosensitivity of 181 and a fast photoresponse time with a rise time of 10.6 ms and fall time of 9.9 ms under 630 nm illumination. Therefore, the Co-doped ZnFe2O4 thin film is favorable for potential photodetector applications in visible light regions.
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Design and exploration of new intermediates for chemo-, regio-, and stereoselective cycloadditions remain a formidable challenge in modern organic synthesis. Compared to the well-developed 1,3-dipolar cycloadditions, Pd-catalyzed1,4-dipolar cycloadditions are generally limited to specialized substrates due to the inherent nature of the thermodynamically driven intramolecular transformations and undesired isomerizations. Herein, we demonstrate the use of ligated palladium catalysts to control and modulate the intermolecular reactivity of aliphatic 1,4-dipoles, enabling two distinctive cycloaddition pathways with a broad scope of acceptors. This atom-economic process also features an eco-friendly in situ deprotonation strategy to generate the corresponding active palladium-mediated dipoles. Overall, a diverse array of chiral 6-membered rings and spiro [2.4] heptanes were prepared in high yield and selectivity. In addition, an unexpected property of cyano-stabilized carbanions was discovered and investigated, which can be useful in designing and predicting future transformations.
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Enantioselective incorporation of trifluoromethyl (-CF3) and trifuoromethylthio (-SCF3) groups in small molecules is of high interest to modulate the potency and pharmacological properties of drug candidates. Herein, we report a Zn-ProPhenol catalyzed diastereo- and enantioselective Mannich addition of α-trifluoromethyl- and α-trifuoromethylthio-substituted ketones. This transformation uses cyclic and acyclic ketones and generates quaternary trifluoromethyl and tetrasubstituted trifuoromethylthio stereogenic centers in excellent yields and selectivities.
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The development of new methodologies that enable chemo- and stereoselective construction of fluorinated substituents, such as the trifluoromethyl (CF3) group, plays an essential role in the synthesis of new pharmaceutical agents. The exceptional ability of the CF3 moiety to prevent in vivo metabolism as well as improve other pharmacological properties has led to numerous innovative strategies for installing this unique functional group. One potential yet underdeveloped approach to access these trifluoromethylated products is direct substitution of α-trifluoromethyl carbanions. Although the electron-withdrawing nature of the CF3 group should facilitate deprotonation of adjacent hydrogens, the propensity of the resulting carbanions to undergo α-elimination of fluoride renders this process highly challenging. Herein, we describe a new strategy for stabilizing and utilizing transient α-trifluoromethyl carbanions that relies on a neighbouring cationic π-allyl palladium complex. These palladium-stabilized zwitterions participate in asymmetric [3 + 2] cycloadditions with a broad range of acceptors, generating valuable di- and trifluoromethylated cyclopentanes, pyrrolidines and tetrahydrofurans.
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The ProPhenol ligand is a member of the chiral aza-crown family that spontaneously forms a bimetallic complex upon treatment with alkyl metal reagents, such as Et2 Zn and Bu2 Mg. The resulting complex features Lewis acidic and Brønsted basic sites, enabling simultaneous activation of both nucleophile and electrophile in the same chiral environment. Since the initial report in 2000, metal-ProPhenol catalysts have been used to facilitate a broad range of asymmetric transformations, including aldol, Mannich, and Henry reactions, as well as alkynylations and conjugation additions. By promoting such a diverse array of reactions, these complexes provide rapid and atom-economical access to valuable complex building blocks. In this Review, we describe in detail the development and synthetic applications of these versatile catalysts with a special focus on recent efforts to improve reactivity and selectivity through ligand design and structural modification.
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The preparation of acyclic ß-fluoro amines bearing tetrasubstituted fluorine stereocenters is described via a direct Zn/ProPhenol-catalyzed Mannich reaction. The reaction utilizes branched vinyl or alkynyl α-fluoro ketones that can be coupled with a range of aryl, heteroaryl, vinyl, or cyclopropyl aldimines in high yield and with excellent diastereo- (up to >20:1) and enantioselectivity (up to 99 %). The use of readily cleaved tert-butoxycarbonyl (Boc) or carboxybenzyl (Cbz) imine protecting groups adds utility to the reaction by allowing for easy access to the free amine products under mild and chemoselective reaction conditions.
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A general method for asymmetric synthesis of heteroaryl-containing cycles via palladium-catalyzed cyclization is reported. Most classes of nitrogen-containing aromatics, including pyridines, quinolines, pyrimidines, various azoles and the derivatives of nucleobases are compatible substrates, offering various heteroaryl-substituted cyclopentane, pyrrolidine, furanidine and bicyclo[4.3.1]decadiene derivatives with good to excellent enantioselectivity and diastereoselectivity.
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The isoquinoline alkaloids isolated from the genus Corydalis possess potent and diverse biological activities. Herein, a concise, divergent, and enantioselective route to access these natural products is disclosed. Key transformations of our approach include a challenging Zn-ProPhenol-catalyzed asymmetric Mannich reaction to build a quaternary stereogenic center and a rapid cationic Au-catalyzed cycloisomerization to the common structural skeleton of these natural products. Subsequent late-stage oxidations and modifications allow efficient access to the targeted alkaloids. Overall, seven natural products have been successfully synthesized in 6 to 10 steps from readily available starting materials, including (+)-corynoline, (+)-anhydrocorynoline, (+)-12-hydroxycorynoline, (+)-12-hydroxycorynoloxine, (+)-corynoloxine, (+)-6-acetonylcorynoline, and (+)-bulleyanaline.
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Alcaloides/síntese química , Corydalis/química , Isoquinolinas/síntese química , Alcaloides/química , Cristalografia por Raios X , Ciclização , Isoquinolinas/química , Estrutura Molecular , EstereoisomerismoRESUMO
Densely substituted chiral pyrrolidones are synthesized via phosphine-catalyzed cycloisomerization of enantioenriched ß-amino ynones, which are prepared in a single step using a highly enantioselective Zn-ProPhenol-catalyzed Mannich reaction. The exocyclic alkenes in the cyclization products provide versatile handles for further transformations and typically form with good E/ Z selectivity. This cycloisomerization method can be performed in streamlined fashion, without purification of the intermediate Mannich adduct, and extends to anthranilic acid based scaffolds in addition to ProPhenol-derived Mannich adducts.
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We report the first enantio- and diastereoselective 1,4-addition of butenolides to chromones. Both α,ß- and ß,γ-butenolide nucleophiles are compatible with the Zn-ProPhenol catalyst, and preactivation as the siloxyfurans is not required. The scope of electrophiles includes a variety of substituted chromones, as well as a thiochromone and a quinolone, and the resulting vinylogous addition products are generated in good yield (31 to 98%), diastereo- (3:1 to >30:1), and enantioselectivity (90:10 to 99:1 er). These Michael adducts allow rapid access to several natural product analogs, and can be easily transformed into a variety of other interesting scaffolds as well.
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We report a Zn-ProPhenol catalyzed asymmetric Mannich reaction between butenolides and polyfluorinated alkynyl ketimines to obtain vinylogous products featuring two contiguous tetrasubstituted stereogenic centers. Notably, this is the first successful use of ketimines in the ProPhenol Mannich process, and the reaction offers a new approach for the preparation of pharmaceutically relevant products possessing trifluoromethylated tetrasubstituted alkylamines. The reaction can be performed on large scale with reduced catalyst loading without impacting its efficiency. Moreover, the acetylene moiety can be further elaborated using various methods.
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4-Butirolactona/análogos & derivados , Alcinos/química , Hidrocarbonetos Fluorados/química , Iminas/química , Nitrilas/química , 4-Butirolactona/síntese química , 4-Butirolactona/química , Alcinos/síntese química , Catálise , Técnicas de Química Sintética , Halogenação , Hidrocarbonetos Fluorados/síntese química , Iminas/síntese química , Metilação , Nitrilas/síntese química , EstereoisomerismoRESUMO
OBJECTIVES: Weight gain and metabolic disturbances such as dyslipidemia, are frequent side effects of second-generation antipsychotics, including olanzapine. This study examined the metabolic effects of chronic olanzapine exposure. In addition, we investigated the hepatic fatty acid effects of olanzapine in female C57BL/6J mice fed a normal diet. MATERIALS AND METHODS: Female C57BL/6J mice orally received olanzapine or normal saline for 7 weeks. The effects of long-term olanzapine exposure on body weight changes, food efficiency, blood glucose, triglyceride (TG), insulin, and leptin levels were observed. Hepatic TG and abdominal fat mass were investigated, and fat cell morphology was analyzed through histopathological methods. The levels of protein markers of fatty acid regulation in the liver, namely fatty acid synthase (FAS) and stearoyl-CoA desaturase-1 (SCD-1), were measured. RESULTS: Olanzapine treatment increased the food intake of the mice as well as their body weight. Biochemical analyses showed that olanzapine increased blood TG, insulin, leptin, and hepatic TG. The olanzapine group exhibited increased abdominal fat mass and fat cell enlargement in abdominal fat tissue. Western blotting of the mouse liver revealed significantly higher (1.6-fold) levels of SCD-1 in the olanzapine group relative to the control group; by contrast, FAS levels in the two groups did not differ significantly. CONCLUSION: Enhanced lipogenesis triggered by increased hepatic SCD-1 activity might be a probable peripheral mechanism of olanzapine-induced dyslipidemia. Some adverse metabolic effects of olanzapine may be related to the disturbance of lipid homeostasis in the liver.
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BACKGROUND: Sexual dysfunction occurs commonly in patients with psychiatric illness and may be related to the primary mental disorder, comorbidity with sexual disorders or medical illness, or medications used for mental disorders treatment, but the magnitude of this problem is unknown. AIM: To estimate the prevalence of current sexual activity, sexual dysfunction, and sexual attitude and influence of factors on patients with schizophrenia. METHODS: This study used a cross-sectional design with a total of 317 patients diagnosed with schizophrenia. The subjects completed a demographic questionnaire, sexual attitude scale, sexual dysfunction scale, and sexual behavior scale. Descriptive analysis, difference analysis, and logistic regression model were used to identify relevant variables that may affect sexual life quality. OUTCOMES: Age, sexual satisfaction, and patient symptoms may predict sexual life quality on patients with schizophrenia. RESULTS: The mean age of patients was 47.71 ± 9.54 years old. About the sexual activities, 53% of subjects had sexual intercourse experience, and 41.3% reported currently having sexual intercourse. The mean ± SD age for first sexual intercourse was 20.83 ± 5.95 years old (median was 20.0 years old). Moreover, women older than 50 years had significantly higher medians for the Brief Psychiatric Rating Scale (BPRS) score, higher proportions of sexual dysfunction, and lower proportions of feeling important to sexual life quality than men. For participants with age ≤50 years old, there was a significant relationship among BPRS group (mean score >2.5 vs ≤2.5), sexual dysfunction (P < .001), sexual life quality (P < .001), and sexual satisfaction (P = .006). Among the predictors of feeling important to sexual life quality, sexual satisfaction (odds ratio = 7.005, 95% CI = 4.126-11.892, P < .001) and BPRS score (odds ratio = 4.501, 95% CI = 2.042-9.923, P < .001) were significant independent factors after adding the interaction of age group and BPRS group. CLINICAL TRANSLATION: This study also reveals the close relationship between sexual satisfaction and BPRS score, which may predict sexual life quality of patients with schizophrenia. Limitations include the possibility of underreporting and bias associated with self-report measurement. CONCLUSION: Sexual life quality and sexual dysfunction on patients with schizophrenia are associated with interaction among psychological, sociological, and biochemical-pharmacological factors. Ma M-C, Chao J-K, Hung J-Y, et al. Sexual Activity, Sexual Dysfunction, and Sexual Life Quality Among Psychiatric Hospital Inpatients With Schizophrenia. J Sex Med 2018;15:324-333.
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Qualidade de Vida , Esquizofrenia/complicações , Comportamento Sexual/estatística & dados numéricos , Disfunções Sexuais Fisiológicas/epidemiologia , Adulto , Idoso , Coito , Estudos Transversais , Feminino , Hospitais Psiquiátricos , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Orgasmo , Prevalência , Inquéritos e Questionários , Adulto JovemRESUMO
Managing patients with chronic pelvic pain syndrome (CPPS) refractory to the traditional 3-As therapy (antibiotics, alpha-blockers, and anti-inflammatories) is a challenging task. Low-intensity extracorporeal shock wave therapy (LI-ESWT) was recently reported to be able to improve pain, urinary symptoms, and even sexual function by inducing neovascularization and anti-inflammation, reducing muscle tone, and influencing nerve impulses. This study evaluates whether combined treatment with LI-ESWT can restore clinical ability and quality of life (QoL) in patients refractory to 3-As therapy. This was an open-label, single-arm prospective study. Patients with CPPS without more than a 6-point decrease in the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) total score under the maximal dosage of 3-As therapy were enrolled. LI-ESWT treatment consisted of 3,000 shock waves administered once weekly for 4 weeks. The NIH-CPSI, visual analog scale (VAS) score, International Prostate Symptom Score (IPSS), and the five-item version of the International Index of Erectile Function (IIEF-5) were used to evaluate efficacy at 1, 4, and 12 weeks after LI-ESWT. Thirty-three patients were enrolled in this study. After LI-ESWT treatment, 27 of the 33 patients (81.82%) had a successful response to LI-ESWT, with a decrease of 3.29 and 5.97 in the VAS score and total IPSS at the 3-month follow-up. Waist circumference was the only significant predictor of a successful response to LI-ESWT. LI-ESWT can serve as a salvage therapy for patients with CPPS refractory to traditional 3-As therapy. Further studies are needed to determine an adequate therapeutic protocol and important predictors in patients with different CPPS etiologies.
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Tratamento por Ondas de Choque Extracorpóreas , Dor Pélvica/tratamento farmacológico , Antagonistas Adrenérgicos alfa/administração & dosagem , Antagonistas Adrenérgicos alfa/farmacologia , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Dor Crônica , Tratamento por Ondas de Choque Extracorpóreas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taiwan , Falha de TratamentoRESUMO
BACKGROUND: Carpal tunnel syndrome (CTS) and trigger digits are among the most common nontraumatic hand disorders treated by plastic surgeons. The onset of trigger digits after carpal tunnel release (CTR) has been inconsistently reported. This systematic review assessed the prevalence of trigger digits development in patients after CTR surgery. METHODS: We searched the MEDLINE, EMBASE and SCOPUS databases for papers published between January 1966 and August 2016. Eligible studies contained quantitative data on the incidence of trigger digits after CTR. The primary outcome measure was the onset of trigger digits after CTR. The secondary outcome measure was the prevalence of digital involvement in patients who developed trigger digits after CTR. RESULTS: A total of 5654 CTR surgeries were performed in the included nine studies, and 483 patients (8.5%) developed trigger digits after CTR. The reported incidence of trigger digits after CTR ranged from 5.2% to 31.7%. The time to development of trigger digits was approximately 6 months postoperatively. In the eight observational studies and in the randomized controlled trial, the thumb and ring finger were reported as the most commonly involved trigger digits, respectively. CONCLUSIONS: The incidence of trigger digits after CTR surgery is not negligible. Thumbs and ring fingers are the most commonly involved digits. This topic should therefore be suitably addressed during preoperative consultations.
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Síndrome do Túnel Carpal/cirurgia , Descompressão Cirúrgica/efeitos adversos , Dedo em Gatilho/epidemiologia , Dedo em Gatilho/etiologia , Adulto , Síndrome do Túnel Carpal/diagnóstico , Descompressão Cirúrgica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Medição de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Dedo em Gatilho/fisiopatologiaRESUMO
In this retrospective observational study performed in a high-volume hepatobiliary-pancreatic unit, we evaluated the effect of a surgery-specific goal-directed therapy (GDT) physiologic algorithm on complications and length of hospital stay. We compared patients who underwent pancreaticoduodenectomy with either a standardised Enhanced Recovery After Surgery program (usual care group), or a standardised Enhanced Recovery After Surgery program in combination with a surgery-specific cardiac output-guided algorithm (GDT group). We included 145 consecutive patients: 47 in the GDT group and 98 in the usual care group. Multivariable associations between GDT and lengths of stay and complications were investigated using negative binomial regression. Postoperative complications were common and occurred at similar frequencies amongst the GDT and usual care groups: 64% versus 68% respectively, P=0.71; odds ratio 0.82; (95% confidence interval 0.39-1.70). There were fewer cardiorespiratory complications in the GDT group. Median (interquartile range) length of hospital stay was ten days (8.0-14.0) in the GDT group compared to 13 days (8.8-21.3) in the usual care group, P=0.01. Median (interquartile range) total intraoperative fluid was 3,000 ml (2,050-4,175) in the GDT group compared to 4,500 ml (3,275-5,325) in the usual care group, P <0.0001; but by day one, the median (interquartile range) fluid balance was similar (1,198 ml [700-1,729] in the GDT group versus 977 ml [419-2,044] in the usual care group, P=0.96). Use of vasoactive medications was higher in the GDT group. In our patients undergoing pancreaticoduodenectomy, GDT was associated with restrictive intraoperative fluid intervention, fewer cardiorespiratory complications and a shorter hospital length of stay compared to usual care. However, we could not exclude an influence of surgical caseload, which we have previously found to be an important variable. We also could not relate the increased hospital length of stay to cardiorespiratory complications in individual patients. Therefore, these observational retrospective findings would require confirmation in a prospective randomised study.