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1.
Adv Clin Exp Med ; 33(3): 207-216, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37486698

RESUMEN

BACKGROUND: Intra-arterial chemotherapy (IAC) is considered a unique technique for retinoblastoma (Rb) management and has widespread applicability as a first-line or second-line treatment due to the high globe survival rates. OBJECTIVES: This meta-analysis aimed to assess the efficacy of IAC approach among patients with Rb. MATERIAL AND METHODS: This study outlined the most recent research on IAC effectiveness in Rb treatment. We carried out a systematic search for published papers examining IAC treatment among patients with Rb using electronic search engines, including Embase, Web of Science (WoS), PubMed, OVID, and Google Scholar, until October 2021. RESULTS: This meta-analysis included 39 observational studies with 2604 treated eyes and 3112 individuals who were eligible for inclusion. Enucleation rates varied from 0% to 43.7% in the chosen trials, with an odds ratio (OR) of 0.52 (95% confidence interval (95% CI): 0.41-0.66, p < 0.0001). A range of 30-100% was reported for globe salvage across 27 investigations involving 2310 eyes. The estimated OR of globe salvage was 2.41, with 95% CI of 1.6-3.63 and a p-value <0.0001. The combined total effect sizes and the death rate for the proportion of cases with metastatic Rb were as follows: OR = 0.03 (95% CI: 0.03-0.03) and OR = 0.05 (95% CI: 0.04-0.05, p < 0.0001), respectively. CONCLUSION: Retrospective trials have shown that intra-arterial-based therapy for Rb is an effective choice. Intra-arterial chemotherapy also reduced enucleation and metastasis incidence rates. The paucity of evidence in the literature necessitates further high-level studies.


Asunto(s)
Neoplasias de la Retina , Retinoblastoma , Humanos , Melfalán/uso terapéutico , Estudios Observacionales como Asunto , Neoplasias de la Retina/tratamiento farmacológico , Neoplasias de la Retina/patología , Retinoblastoma/patología , Estudios Retrospectivos , Resultado del Tratamiento
2.
Curr Med Imaging ; 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37317910

RESUMEN

BACKGROUND Arthritis of the hip caused by arteriovenous malformations (AVMs) has been rarely reported. Therefore, total hip replacement (THR) in patients with AVM-induced arthritis of the hip is challenging. CASE SUMMARY We report a 44-year-old woman with aggravated right hip pain during the past decade. The patient presented with severe pain and a functional disorder of the right hip. X-ray examination revealed severely narrowed right hip joint space and abnormal trabecular bone loss in the femoral neck and trochanter area. Doppler ultrasound, magnetic resonance imaging and computed tomography angiography revealed AVMs surrounding the right hip, along with erosion. To ensure the safety of THR, we performed vascular embolization and temporary balloon occlusion of the iliac artery three times during the operation. However, serious hemorrhage occurred, which was rescued by the multimodality blood conservation strategy. THR was successfully performed, and the patient was discharged 8 d later for rehabilitation. Postoperative pathological examination showed osteonecrosis of the femoral head with malformed thick-walled vessels and focal granulomatous inflammation of the surrounding soft tissues. The Harris Hip Scale score increased from 31 to 82 at 3 mo of follow-up. The patient was followed up for 1 year, and all her clinical symptoms were significantly alleviated. CONCLUSION Arthritis of the hip caused by AVMs is rare in clinical practice. The activity and function of the involved hip joint can be effectively treated with THR after comprehensive imaging and multidisciplinary consultation.

3.
Connect Tissue Res ; 64(5): 445-456, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37171221

RESUMEN

PURPOSE/AIM: Bone defects caused by trauma, tumors, congenital malformation, or inflammation are very common in orthopedics. In recent years, mimicking the composition and structure of natural bone tissue has become a hot topic in biomaterial research, with the aim of developing an ideal biomaterial for bone defect transplantation. Here, the feasibility of a biphasic calcium phosphate (BCP)/acylated methacrylate gelatin (GelMA) composite hydrogel to repair bone defects was evaluated in vitro and in rats. MATERIALS AND METHODS: The biocompatibility of a biphasic calcium phosphate (BCP)/acylated methacrylate gelatin (GelMA) composite hydrogel was evaluated by cytoskeleton staining, live/dead cell staining and cell proliferation assays. The in vitro osteogenic activities of the composite hydrogel were evaluated by alkaline phosphatase and alizarin red staining, as well as osteogenic gene expression analysis at both transcript and protein levels. The in vivo bone repair activities were evaluated using the rat skull defect model. RESULTS: The BCP/GelMA composite hydrogel displayed excellent biocompatibility and promoted osteogenesis of bone marrow mesenchymal stem cells in vitro. In addition, the BCP/GelMA composite hydrogel markedly promoted new bone formation in the rat skull-defect model. CONCLUSIONS: BCP/GelMA composite hydrogel may be an effective artificial material for bone tissue engineering.


Asunto(s)
Hidrogeles , Osteogénesis , Ratas , Animales , Hidrogeles/farmacología , Hidrogeles/química , Gelatina/farmacología , Gelatina/química , Andamios del Tejido/química , Metacrilatos/farmacología , Metacrilatos/química , Materiales Biocompatibles/química , Ingeniería de Tejidos
4.
Polymers (Basel) ; 15(9)2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37177230

RESUMEN

The present paper aims to investigate the buckling load of functionally graded carbon-fiber-reinforced polymer (FG-CFRP) composite laminated plates under in-plane loads in a thermal environment. The effective material properties of the CFRP composite are calculated by the Mori-Tanaka homogenization method. The theoretical formulations are based on classical laminate plate theory (CLPT) and the von Kármán equations for large deflections. The governing equations are derived based on the principle of virtual work and then solved through the Navier solution. Results are obtained for the critical buckling load and temperature effect of a simply supported plate subjected to in-plane loading. A detailed numerical study is conducted to provide important insights into the effects of the functionally graded carbon fiber (CF) distribution pattern and volume fraction, total number of layers, temperature, geometrical dimension and lamination angle on the buckling load of functionally carbon-fiber-reinforced composite plates. Finally, the validation is compared with the Reddy and finite element analyses, which show consistency with each other.

5.
IEEE Trans Pattern Anal Mach Intell ; 45(7): 9135-9148, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37015576

RESUMEN

Cross-spectral face hallucination is an intuitive way to mitigate the modality discrepancy in Heterogeneous Face Recognition (HFR). However, due to imaging differences, the hallucination inevitably suffers from a shape misalignment between paired heterogeneous images. Rather than building complicated architectures to circumvent the problem like previous works, we propose a simple yet effective method called Shape Alignment FacE (SAFE). Specifically, given an image, we align its shape to that of the paired one under the assistance of a 3D face model. The produced aligned pair enables us to train a lightweight generator that solely concentrates on spectrum translation with a pixel-wise supervision. However, since the 3D face model is powerless to attributes like the hair and glasses, there are still pixel discrepancies between the aligned pair. Given that, in the image space, we introduce a probabilistic pixel-wise loss that incorporates the discrepancies into a probabilistic distribution. Moreover, in order to alleviate the influence of the shape misalignment on spectrum translation, a spectrum optimal transport is performed in a shape-irrelevant latent space. Note that, in the final inference phase, except the lightweight generator, all other auxiliary modules are discarded. In addition to superior performance in qualitative synthesis and quantitative recognition, extensive experiments on 6 datasets demonstrate that our method also gains other two distinct advantages over existing state-of-the-art counterparts. The first is using a more lightweight generator. Compared with the state-of-the-art method, our method can achieve higher recognition results with 128x fewer parameters and 63x fewer FLOPs with only 4.58 ms latency on a single TITAN-XP. The second is training on low-shot datasets such as Oulu-CASIA NIR-VIS that just contains 1,920 images from 20 identities. To the best of our knowledge, we are the first that can perform well on such a small-scale dataset. These advantages make our method more practical in the real world and further push boundaries of heterogeneous face recognition.

6.
J Orthop Surg Res ; 18(1): 217, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36935479

RESUMEN

BACKGROUND: The optimal tibial component rotational alignment in unicompartmental knee arthroplasty has not been defined. This study aimed to explore the effect of tibial component rotational alignment on the clinical outcomes of UKA. METHODS: Clinical and follow-up data from 269 patients were retrospectively analysed. They were assigned into Groups A (- 5° to 0°), B (0°-3°), C (3°-6°) and D (> 6°) according to the external rotation of the tibial component to Akagi's line. The Knee Society Score clinical (KSS-c), Knee Society Score function (KSS-f), Forgotten Joint Score (FJS) and postoperative complications at 2 years postsurgically were analysed. RESULTS: The mean rotation of the tibial component relative to Akagi's line in 269 patients was 4.56 ± 3.79°. There were 15, 84, 89 and 81 patients in Groups A, B, C and D, respectively. The postoperative KSS-c and KSS-f in Groups B and C were significantly higher than those in Group D. No significant differences in KSS-c and KSS-f were detected between Groups B and C. The postoperative FJS in Group B was significantly higher than that in Group C, which was significantly higher in Group C than in Group D. There were 5, 8 and 15 cases of postoperative knee pain in Groups B, C and D, respectively, and the difference was statistically significant. CONCLUSION: Tibial component rotational alignment is of significance to Oxford Phase III UKA in patients. External rotation of the tibial component by 0°-3° is optimal to achieve satisfactory clinical outcomes.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Humanos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Tibia/diagnóstico por imagen , Tibia/cirugía , Dolor Postoperatorio/cirugía , Osteoartritis de la Rodilla/cirugía
7.
Am J Transl Res ; 15(1): 193-201, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36777841

RESUMEN

OBJECTIVE: To investigate the efficacy of laser photocoagulation combined with ranibizumab in patients with diabetic retinopathy and their effect on VEGF. METHODS: The medical records of 98 patients with diabetic retinopathy treated in the First People's Hospital of Linping District from February 2020 to January 2022 were collected for a retrospective analysis. Among them, 48 patients treated with laser photocoagulation were a control group (CG), and another 50 treated with laser photocoagulation combined with ranibizumab were an observation group (OG). The treatment efficacy, best corrected visual acuity (BCVA), central macular concave thickness (CMT), and change in neovascularization area were compared between the two groups. Also, the changes in serum vascular endothelial growth factor (VEGF), homocysteine (HCY), vitamin B12 and folic acid were compared. The adverse effects that occurred with treatment were assessed. The relationship of pre-treatment BCVA, CMT, neovascularization area and VEGF levels with clinical outcomes were observed, and their predictive values were analyzed by receiver operating characteristic (ROC) curve. RESULTS: The total response rate of patients in the CG was lower than that in the OG (P<0.05). The BCVA, CMT, and neovascularization area were dramatically lower, while vitamin B12 and folic acid were markedly higher in the OG than in the CG after treatment (P<0.05). There was no statistical difference in adverse reactions between the two groups (P>0.05). In patients with effective response, the BCVA, CMT, VEGF and Hcy before treatment were dramatically lower than in those with ineffective response (P<0.05), while the neovascularization area, vitamin B12, and folic acid did not differ between them before treatment (P>0.05). ROC curve analysis revealed that the areas under the curve of BCVA, CMT, VEGF and Hcy were all greater than 0.7 for predicting patient outcomes, and the area under the curve of the combination of the above indexes was 0.945, with a specificity of 92.30% and sensitivity of 88.23%. CONCLUSION: Laser photocoagulation combined with ranibizumab may provide good therapeutic efficacy in diabetic retinopathy, by effectively improving neovascularization and reducing VEGF levels to control further progression of the lesions.

8.
Materials (Basel) ; 17(1)2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38204086

RESUMEN

This analysis investigated the impact wave response and propagation on a composite sandwich shell when subjected to a low-velocity external shock, considering hygrothermal effects. The sandwich shell was crafted using face layers composed of functional gradient metal-ceramic matrix material and a core layer reinforced with negative Poisson's honeycomb. The honeycomb layer consisted of a combination of viscoelastic polymer material and elastic material. The equivalent parameters for the functional gradient material in the face layers were determined using the Mori-Tanaka and Voigt models, and the parameters for the negative Poisson's ratio honeycomb reinforcement core layer were obtained through Gibson's unit cell model. Parameters relevant to a low-velocity impact were derived using a modified Hertz contact law. The internal deformations, strains, and stress of the composite sandwich shell were described based on the higher-order shear deformation theory. The dynamic equilibrium equations were established using Hamilton's principle, and the Galerkin method along with the Newmark direct integration scheme was employed to calculate the shell's response to impact. The validity of the analysis was confirmed through a comparison with published literature. This investigation showed that a multilayer negative Poisson's ratio viscoelastic polymer material honeycomb-cored structure can dissipate impact wave energy swiftly and suppress shock effectively.

9.
Front Pediatr ; 9: 775488, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34869127

RESUMEN

Background: FERM domain-containing protein 4A (FRMD4A) is a scaffolding protein previously proposed to be critical in the regulation of cell polarity in neurons and implicated in human intellectual development. Case Presentation: We report a case of a 3-year-old boy with corpus callosum anomaly, relative macrocephaly, ataxia, and unexplained global developmental delay. Here, compound heterozygous missense mutations in the FRMD4A gene [c.1830G>A, p.(Met610Ile) and c.2973G>C, p.(Gln991His)] were identified in the proband, and subsequent familial segregation showed that each parent had transmitted a mutation. Conclusions: Our results have confirmed the associations of mutations in the FRMD4A gene with intellectual development and indicated that for patients with unexplained global developmental delay, the FRMD4A gene should be included in the analysis of whole exome sequencing data, which can contribute to the identification of more patients affected by this severe phenotypic spectrum.

10.
Orthop Surg ; 13(6): 1802-1809, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34351048

RESUMEN

OBJECTIVE: To compare early clinical effects of the femoral neck system (FNS) and three cannulated screws for the treatment of patients with unstable femoral neck fractures. METHODS: A retrospective analysis with pair matching of 81 patients who received FNS or cannulated screw internal fixation for Pauwels type-3 femoral neck fracture in our hospital from January 2019 to December 2019 was conducted. Patients who received FNS were the test group, and those who received cannulated screws comprised the control group. Matching requirements were as follows: same sex, similar age, and similar body mass index (BMI). A total of 30 pairs were successfully matched at a 1:1 ratio, including 12 males and 18 females. The average age of the patients in the FNS group was 54.53 ± 6.71 years. In the cannulated screw group, the average age of the patients was 53.14 ± 7.19 years. The operation time, intraoperative blood loss, hospital stay, hospitalization cost, postoperative visual analog scale (VAS) score, time to walking without crutches, Harris score, femoral head necrosis rate, and complication rate were compared between the groups. RESULTS: Postoperative re-examination of radiographs showed satisfactory reduction in all patients, and all patients were followed up for 10-22 months. Those in the FNS group had lower postoperative VAS scores, earlier times to walking without crutches, higher Harris scores at the last follow-up, and lower complication rates (P < 0.05). VAS scores were lower in the FNS group (3.13 ± 1.07 scores) than in the cannulated screw group (3.77 ± 1.04 scores) (P = 0.018). Patients in the FNS group (5.23 ± 1.33 months) recovered to walking without crutches earlier than did those in the cannulated screw group (6.03 ± 1.45 months) (P<0.001). In addition, a statistically higher postoperative Harris score was detected in the FNS group (86.16 ± 7.26) than in the cannulated screw group (82.37 ± 7.52) (P = 0.039). Overall, a higher incidence of complications was observed in the cannulated screw group (9/30) than in the FNS group (2/30) (P = 0.042). However, intraoperative blood loss and hospitalization costs were greater in the FNS group (P < 0.05). Intraoperative blood loss was greater in the FNS group (99.73 ± 4.69) than in the cannulated screw group (30.27 ± 9.04) (P<0.001). In addition, patients in the FNS group (46976 ± 2270 ¥) spent more on hospitalization costs than did those in the cannulated screw group (15626 ± 1732 ¥) (P<0.001). No statistically significant difference in operation time, hospital stay, or femoral head necrosis rate was observed between the two groups (P > 0.05). CONCLUSION: For patients with unstable femoral neck fractures, FNS has better clinical efficacy than cannulated screws, though it is also more expensive.


Asunto(s)
Tornillos Óseos , Fracturas del Cuello Femoral/cirugía , Fijación Interna de Fracturas/métodos , Femenino , Fijación Interna de Fracturas/instrumentación , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Medición de Resultados Informados por el Paciente , Complicaciones Posoperatorias , Estudios Retrospectivos , Resultado del Tratamiento
11.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(10): 1164-1171, 2020 Oct 28.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-33268576

RESUMEN

OBJECTIVES: Primary carnitine deficiency (PCD) is a rare fatty acid metabolism disorder that can cause neonatal death. This study aims to analyze carnitine levels and detect SLC22A5 gene in newborns with carnitine deficiency, to provide a basis for early diagnosis of PCD, and to explore the relationship between carnitine in blood and SLC22A5 genotype. METHODS: A total of 40 neonates with low free carnitine (C0<10 µmol/L) in blood were the subjects of the study. SLC22A5 gene was detected by Sanger sequencing to analyze the value of carnitine, the results of gene test and their relationship. RESULTS: A total of 15 variants of SLC22A5 gene were detected, including 11 pathogenic or likely pathogenic variants and 4 variants of uncertain significance. There were 5 new mutations: c.288delG (p.G96fsX33), c.744_745insTCG (p.M258_L259insS), c.752A>G (p.Y251C), c.495 C>A (p.R165E), and c.1298T>C (p.M433T). We found 14 PCD patients including 2 homozygous mutations and 12 heterozygous mutations, 14 with 1 mutation, and 12 with no mutation among 40 children. The C0 concentration of children with SLC22A5 gene homozygous or complex heterozygous mutations was (4.95±1.62) µmol/L in the initial screening, and (3.90±1.33) µmol/L in the second screening. The C0 concentration of children with no mutation was (7.04±2.05) µmol/L in the initial screening, and (8.02±2.87) µmol/L in the second screening. There were significant differences between children with homozygous or compound heterozygous mutations and with no mutation in C0 concentration of the initial and the second screening (both P<0.05), as well as between children with truncated mutation and with untruncated mutation in C0 concentration of the initial screening (P=0.022). CONCLUSIONS: There are 5 new mutations which enriched the mutation spectrum of SLC22A5 gene. C0<5 µmol/L is highly correlated with SLC22A5 gene homozygous or compound heterozygous mutations. Children with truncated mutation may have lower C0 concentration than that with untruncated mutation in the initial screening.


Asunto(s)
Hiperamonemia , Enfermedades Musculares , Cardiomiopatías , Carnitina/deficiencia , Niño , Humanos , Hiperamonemia/genética , Recién Nacido , Enfermedades Musculares/genética , Mutación , Miembro 5 de la Familia 22 de Transportadores de Solutos/genética
12.
Org Biomol Chem ; 18(9): 1733-1737, 2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-32048693

RESUMEN

A novel TBPB-initiated cascade cyclization of 3-arylethynyl-[1,1'-biphenyl]-2-carbonitriles with sulfinic acids via C-S, C-C and C-N bond formation for the synthesis of 3-sulfonated cyclopenta[gh]phenanthridines under metal-free conditions has been developed. This protocol features mild conditions, good functional group tolerance and a broad substrate scope. By using this protocol, a variety of potentially bioactive 3-sulfonated cyclopenta[gh]phenanthridines were facilely synthesized via direct annulation.

13.
Open Life Sci ; 15(1): 488-500, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33817237

RESUMEN

BACKGROUND: Dysregulation of long noncoding RNAs (lncRNAs) is associated with drug resistance in multiple cancers. We explored the roles of lncRNA p38 inhibited cutaneous squamous cell carcinoma-associated lincRNA (PICSAR) in cisplatin (DDP) resistance of cutaneous squamous cell carcinoma (CSCC). METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to measure the expression of lnc-PICSAR, miR-485-5p and reversionless 3-like (REV3L) mRNA. The cell counting kit-8 (CCK-8) assay was conducted to evaluate DDP resistance and cell viability. The transwell assay was performed to determine cell migration and invasion. Western blot assay and immunohistochemistry (IHC) staining assay were carried out to measure protein levels. The dual-luciferase reporter assay was used to investigate the association between miR-485-5p and lnc-PICSAR or REV3L. Murine xenograft model was constructed to explore the function of lnc-PICSAR in vivo. The morphology of exosomes was analyzed by transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). RESULTS: Lnc-PICSAR was elevated in DDP-resistant CSCC cells. Lnc-PICSAR silencing suppressed cell viability, DDP resistance, migration and invasion in DDP-resistant CSCC cells. MiR-485-5p acted as a target of lnc-PICSAR, and miR-485-5p inhibition reversed the impacts of lnc-PICSAR silencing on DDP resistance and cell progression in DDP-resistant CSCC cells. Lnc-PICSAR promoted REV3L expression via sponging miR-485-5p. Moreover, REV3L overexpression overturned the effects of lnc-PICSAR on cell progression and DDP resistance. Lnc-PICSAR knockdown suppressed DDP resistance in vivo. In addition, lnc-PICSAR was increased in the exosomes derived from CSCC patients' serum and CSCC cells. CONCLUSION: Lnc-PICSAR enhanced DDP resistance via miR-485-5p/REV3L axis in DDP-resistant CSCC cells. Besides, exosome-mediated lnc-PICSAR might be involved in the regulation of drug resistance in CSCC.

14.
Org Biomol Chem ; 17(2): 240-243, 2019 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-30534708

RESUMEN

Indole is a ubiquitous structural motif with important applications in many areas of chemistry. Given this, a simple and efficient Ru(ii)-catalyzed synthesis of indole via intermolecular annulation of N-aryl-2-aminopyridines and sulfoxonium ylides was proposed and accomplished. Excellent selectivity and good functional group tolerance of this transformation were observed. This protocol provides easy access to a wide variety of useful indoles in the presence of a commercially available [Ru(p-cymene)Cl2]2 catalyst. A possible mechanism for the reaction pathway was also proposed. More importantly, this reaction will offer a useful method for the construction of enantioenriched indole frameworks.

15.
Org Biomol Chem ; 15(35): 7365-7368, 2017 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-28829100

RESUMEN

Copper catalyzed chemoselective cleavage of the C(CO)-C(alkyl) bond leading to C-N bond formation with chelation assistance of N-containing directing groups is described. Inexpensive Cu(ii)-acetate serves as a convenient catalyst for this transformation. This method highlights the emerging strategy to transform unactivated alkyl ketones into amides in organic synthesis and provides a new strategy for C-C bond cleavage.


Asunto(s)
Amidas/síntesis química , Monóxido de Carbono/química , Carbono/química , Cobre/química , Cetonas/química , Amidas/química , Catálisis , Estructura Molecular
16.
J Org Chem ; 82(4): 2107-2113, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28121435

RESUMEN

A novel and concise method for the oxidation of unprotected indole derivatives to synthesize 2-indolylbenzoxazinones in the presence of AIBN under open air has been successfully demonstrated. This metal-free reaction is both atom- and step-efficient and is applicable to a broad scope of substrates. This new methodology provides a facile pathway for oxidative C2-C3 bond cleavage and recyclization of 1H-indoles.

17.
Org Biomol Chem ; 14(42): 10070-10073, 2016 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-27722692

RESUMEN

Hydrogen peroxide and anhydride mediated transformation of enamides to afford substituted α-acyloxy ketones is described. This transition-metal-free cascade reaction has a broad substrate scope and high efficiency. The acyl intramolecular migration procedure successfully achieved this acyloxylation process under mild conditions and increased the atom efficiency.

18.
Chem Asian J ; 11(20): 2829-2833, 2016 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-27582251

RESUMEN

A novel and convenient one-pot route for the synthesis of 3-benzyl-2-phenylquinolin-4(1 H)-ones has been developed under transition-metal-free conditions. This new strategy features high yield and good functional group tolerance. In addition, a proposed mechanism has been confirmed for this reaction.

19.
J Org Chem ; 81(1): 25-31, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26624930

RESUMEN

A conversion of pyridines and enamides for the synthesis of 3-bromo-imidazo[1,2-a]pyridines was developed by copper-mediated aerobic oxidative coupling in a one-pot manner. This procedure tolerates various functional groups and affords a series of 3-bromo-imidazo[1,2-a]pyridines under mild conditions.

20.
J Org Chem ; 79(21): 10641-7, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25275820

RESUMEN

A direct method for the synthesis of substituted indolizines by means of I2-mediated oxidative tandem cyclization via C-N/C-C bond formation was developed. Various substituted aromatic/aliphatic enolizable aldehydes and 2-pyridylacetates/acetonitrile/acetone proceeded smoothly in this transformation, and the desired products were generated in moderate to good yields.


Asunto(s)
Acetonitrilos/química , Indolizinas/síntesis química , Yodo/química , Piridinas/química , Catálisis , Ciclización , Indolizinas/química , Estructura Molecular , Oxidación-Reducción
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