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1.
Org Lett ; 23(20): 7703-7707, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34605654

RESUMO

The δ-sulfonamido-substituted enones were employed as phosphine acceptor in phosphine-catalyzed (4 + 2) annulation of 1,1-dicyanoalkenes. They served as a four-membered synthon to react with 1,1-dicyanoalkenes under mild reaction conditions, producing piperidine derivatives in moderate to excellent yields with good to excellent diastereoselectivities.

2.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(8): 858-864, 2021 Aug 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34565730

RESUMO

OBJECTIVES: Previous studies on brain MRI image segmentation, such as threshold method, boundary detection method, and region method did not achieve good performance in complex scenes. Based on the deep learning segmentation technology, this study constructed a neural network model by using the algorithm of atrous convolution combined with conditional random field (CRF) to segment the thalamus, caudate nucleus, and lenticular nucleus in brain MRI, which laid a good foundation for MRI diagnosis of brain diseases. METHODS: A total of 1 200 MRI-Flair images of the brain were randomly selected, and 3 anatomical structures of thalamus, caudate nucleus, and lenticular nucleus were manually labeled, of which 1 000 were used as training data sets and 200 were used as test data sets. The neural network model was established by using deep convolutional neural networks (DCNN) combined with CRF algorithm. The training data set was input into the model, and the parameterized neural network model was obtained after iteration for 30 000 times. The test data set was used to evaluate, test, and output the predicted image. RESULTS: The model optimization results showed that the new brain MRI segmentation model DeepXAG had the highest accuracy. Therefore, DeepXAG was selected as the segmentation algorithm. The mean intersection over union (mIOU) of the DeepXAG model was 72.3%, which was significantly higher than other classical segmentation algorithms (CRF-RNN1, FCN-8s2, DPN3, RefineNet4, and PSPNet5). CONCLUSIONS: The DeepXAG algorithm has good accuracy and robustness in segmenting the anatomical structure of brain MRI images.


Assuntos
Aprendizado Profundo , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Semântica
3.
J Neurosci ; 41(39): 8163-8180, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34385359

RESUMO

Sox10 is a well known factor to control oligodendrocyte (OL) differentiation, and its expression is regulated by Olig2. As an important protein kinase, Akt has been implicated in diseases with white matter abnormalities. To study whether and how Akt may regulate OL development, we generated OL lineage cell-specific Akt1/Akt2/Akt3 triple conditional knock-out (Akt cTKO) mice. Both male and female mice were used. These mutants exhibit a complete loss of mature OLs and unchanged apoptotic cell death in the CNS. We show that the deletion of Akt three isoforms causes downregulation of Sox10 and decreased levels of phosphorylated FoxO1 in the brain. In vitro analysis reveals that the expression of FoxO1 with mutations on phosphorylation sites for Akt significantly represses the Sox10 promoter activity, suggesting that phosphorylation of FoxO1 by Akt is important for Sox10 expression. We further demonstrate that mutant FoxO1 without Akt phosphorylation epitopes is enriched in the Sox10 promoter. Together, this study identifies a novel FoxO1 phosphorylation-dependent mechanism for Sox10 expression and OL differentiation.SIGNIFICANCE STATEMENT Dysfunction of Akt is associated with white matter diseases including the agenesis of the corpus callosum. However, it remains unknown whether Akt plays an important role in oligodendrocyte differentiation. To address this question, we generated oligodendrocyte lineage cell-specific Akt1/Akt2/Akt3 triple-conditional knock-out mice. Akt mutants exhibit deficient white matter development, loss of mature oligodendrocytes, absence of myelination, and unchanged apoptotic cell death in the CNS. We demonstrate that deletion of Akt three isoforms leads to downregulation of Sox10, and that phosphorylation of FoxO1 by Akt is critical for Sox10 expression. Together, these findings reveal a novel mechanism to regulate Sox10 expression. This study may provide insights into molecular mechanisms for neurodevelopmental diseases caused by dysfunction of protein kinases.


Assuntos
Encéfalo/metabolismo , Diferenciação Celular/fisiologia , Oligodendroglia/citologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição SOXE/metabolismo , Medula Espinal/metabolismo , Animais , Apoptose/fisiologia , Feminino , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Masculino , Camundongos , Camundongos Knockout , Oligodendroglia/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Fatores de Transcrição SOXE/genética , Substância Branca/metabolismo
4.
Org Lett ; 23(17): 6780-6783, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34432980

RESUMO

An efficient K2CO3-catalyzed 1,4-addition/intramolecular cyclization/aromatization reaction of aurone-derived 1-azadienes with trisubstituted allenoates has been developed, giving a series of benzofuro[3,2-b]pyridines in moderate to excellent yields. The reaction proceeded efficiently under an air atmosphere without the use of transition metal catalysts. This protocol provides a concise approach to benzofuro[3,2-b]pyridines.

5.
Org Lett ; 23(15): 5750-5754, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34286988

RESUMO

In this paper, we designed and synthesized a new type of cyclic carbonates, allenylethylene carbonates (AECs). With AECs as reactive precursors, we developed palladium-catalyzed (3+3) annulation of AECs with nitrile oxides. Various AECs worked well in this reaction under mild reaction conditions. A variety of 5,6-dihydro-1,4,2-dioxazine derivatives with allenyl quaternary stereocenters can be accessed in a facile manner in high yields (≤98%).

6.
Chem Commun (Camb) ; 57(65): 8059-8062, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34296236

RESUMO

In this paper, an asymmetric allylic alkylation of easily available azomethine ylides with Morita-Baylis-Hillman (MBH) carbonates through a copper (i)/Lewis base cooperative catalysis strategy has been realized. The co-catalyzed asymmetric allylic alkylation provided the corresponding amino acid derivatives in up to 90% yields with up to 99% ee as well as good to excellent regioselectivity.

7.
Langmuir ; 37(23): 7067-7077, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34080864

RESUMO

Lamellar liquid crystals have amazing lubricating and drug-solubilizing properties. Hence, the combination of drug molecules with lamellar liquid crystals is expected to be used in joint lubrication and treatment. In this study, the partial phase diagram of the Tween 85/Tween 80/H2O three-component system was determined. The phase structure of the system changed from a hexagonal liquid crystal to a lamellar liquid crystal with the increase of Tween 85 content. The lamellar liquid crystals showed superior lubricating properties due to their unique lamellar structure. Furthermore, the model of drug release during friction was established for the first time. It was found that the order of the lamellar liquid crystals increased with the increase of the mass ratio of Tween 85/Tween 80, leading to the decrease of the ibuprofen release rate. In addition, the release rate of ibuprofen increased progressively with the increase of the friction frequency, but the load had little effect on it. Therefore, the lamellar liquid crystals consisting of nonionic surfactants with good biocompatibility have potential application prospects for joint lubrication and treatment of arthritis.

8.
Org Lett ; 23(13): 4971-4975, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34114466

RESUMO

An unprecedented C═C double bond cleavage of cyclopropenone and dioxygen activation by multiyne cascade coupling has been developed. This chemistry provides a novel, simple, and efficient approach to synthesize fully substituted conjugate benzofuran derivatives from simple substrates under mild conditions. The density functional theory (DFT) calculations reveal that the unique homolytic cleavages of cyclopropenone and molecular oxygen are crucial to the success of this reaction.

9.
Phys Med ; 85: 147-157, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34010803

RESUMO

PURPOSE: To present an overview of the status of medical physics in radiotherapy in China, including facilities and devices, occupation, education, research, etc. MATERIALS AND METHODS: The information about medical physics in clinics was obtained from the 9-th nationwide survey conducted by the China Society for Radiation Oncology in 2019. The data of medical physics in education and research was collected from the publications of the official and professional organizations. RESULTS: By 2019, there were 1463 hospitals or institutes registered to practice radiotherapy and the number of accelerators per million population was 1.5. There were 4172 medical physicists working in clinics of radiation oncology. The ratio between the numbers of radiation oncologists and medical physicists is 3.51. Approximately, 95% of medical physicists have an undergraduate or graduate degrees in nuclear physics and biomedical engineering. 86% of medical physicists have certificates issued by the Chinese Society of Medical Physics. There has been a fast growth of publications by authors from mainland of China in the top international medical physics and radiotherapy journals since 2018. CONCLUSIONS: Demand for medical physicists in radiotherapy increased quickly in the past decade. The distribution of radiotherapy facilities in China became more balanced. High quality continuing education and training programs for medical physicists are deficient in most areas. The role of medical physicists in the clinic has not been clearly defined and their contributions have not been fully recognized by the community.


Assuntos
Radioterapia (Especialidade) , China , Física Médica , Radioterapia , Inquéritos e Questionários
10.
J Neurosci ; 41(23): 4976-4990, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-33972402

RESUMO

Mutations on γ-secretase subunits are associated with neurologic diseases. Whereas the role of γ-secretase in neurogenesis has been intensively studied, little is known about its role in astrogliogenesis. Recent evidence has demonstrated that astrocytes can be generated from oligodendrocyte precursor cells (OPCs). However, it is not well understood what mechanism may control OPCs to differentiate into astrocytes. To address the above questions, we generated two independent lines of oligodendrocyte lineage-specific presenilin enhancer 2 (Pen-2) conditional KO mice. Both male and female mice were used. Here we demonstrate that conditional inactivation of Pen-2 mediated by Olig1-Cre or NG2-CreERT2 causes enhanced generation of astrocytes. Lineage-tracing experiments indicate that abnormally generated astrocytes are derived from Cre-expressing OPCs in the CNS in Pen-2 conditional KO mice. Mechanistic analysis reveals that deletion of Pen-2 inhibits the Notch signaling to upregulate signal transducer and activator of transcription 3, which triggers activation of GFAP to promote astrocyte differentiation. Together, these novel findings indicate that Pen-2 regulates the specification of astrocytes from OPCs through the signal transducer and activator of transcription 3 signaling.SIGNIFICANCE STATEMENT Astrocytes and oligodendrocyte (OLs) play critical roles in the brain. Recent evidence has demonstrated that astrocytes can be generated from OL precursor cells (OPCs). However, it remains poorly understood what mechanism governs the differentiation of OPCs into astrocytes. In this study, we took advantage of OL lineage cells specific presenilin enhancer 2 (Pen-2) conditional KO mice. We show that deletion of Pen-2 leads to dramatically enhanced astrocyte differentiation from OPCs in the CNS. Mechanistic analysis reveals that deletion of Pen-2 inhibits Hes1 and activates signal transducer and activator of transcription 3 to trigger GFAP activation which promotes astrocyte differentiation. Overall, this study identifies a novel function of Pen-2 in astrogliogenesis from OPCs.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Astrócitos/citologia , Neurogênese/fisiologia , Células Precursoras de Oligodendrócitos/citologia , Animais , Diferenciação Celular/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
11.
Front Psychiatry ; 12: 554435, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33633601

RESUMO

Context: Since December 2019, more than 80,000 patients have been diagnosed with coronavirus disease 2019 (COVID-19) in China. Social support status of COVID-19 patients, especially the impact of social support on their psychological status and quality of life, needs to be addressed with increasing concern. Objectives: In this study, we used social support rating scale (SSRS) to investigate the social support in COVID-19 patients and nurses. Methods: The present study included 186 COVID-19 patients at a Wuhan mobile cabin hospital and 234 nurses at a Wuhan COVID-19 control center. Responses to a mobile phone app-based questionnaire about social support, anxiety, depression, and quality of life were recorded and evaluated. Results: COVID-19 patients scored significantly lower than nurses did on the Social Support Rating Scale (SSRS). Among these patients, 33.9% had anxiety symptoms, while 23.7% had depression symptoms. Overall SSRS, subjective social support scores and objective support scores of patients with anxiety were lower than those of patients without anxiety. This result was also found in depression. In addition, all dimensions of social support were positively correlated with quality of life. Interestingly, in all dimensions of social support, subjective support was found to be an independent predictive factor for anxiety, depression, and quality of life, whereas objective support was a predictive factor for quality of life, but not for anxiety and depression via regression analysis. Conclusion: Medical staffs should pay attention to the subjective feelings of patients and make COVID-19 patients feel respected, supported, and understood from the perspective of subjective support, which may greatly benefit patients, alleviate their anxiety and depression, and improve their quality of life.

12.
Psychopharmacology (Berl) ; 238(4): 949-958, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33544194

RESUMO

Clinical evidence shows that chronic pain and depression often accompany each other, but the underlying pathogenesis of comorbid chronic pain and depression remains mostly undetermined. Biotechnology is gradually revealing the phenotype and function of microglia, with great progress regarding microglia's role in neurodegeneration, depression, chronic pain, and other conditions. This article summarizes the role of microglia in chronic pain, depression, and comorbidities, which is conducive to finding new targets to treat chronic pain and depression.


Assuntos
Dor Crônica/fisiopatologia , Depressão/fisiopatologia , Microglia , Animais , Comorbidade , Humanos
13.
Org Biomol Chem ; 19(3): 557-560, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33399609

RESUMO

A mild Rh-catalyzed method for synthesis of cyclic unprotected N-Me and N-H 2,3-aminoethers using an olefin aziridination-aziridine ring-opening domino reaction has been developed. The method is readily applicable to the stereocontrolled synthesis of a variety of 2,3-disubstituted aminoether O-heterocyclic scaffolds, including tetrahydrofurans, tetrahydropyrans and chromanes.


Assuntos
Éteres/química , Compostos Heterocíclicos/química , Compostos Heterocíclicos/síntese química , Nitrogênio/química , Técnicas de Química Sintética , Hidrogênio/química , Estereoisomerismo
14.
CNS Neurosci Ther ; 27(2): 174-185, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32961023

RESUMO

INTRODUCTION: Presenilin enhancer2 (Pen-2) is an essential subunit of γ-secretase, which is a key protease responsible for the cleavage of amyloid precursor protein (APP) and Notch. Mutations on Pen-2 cause familial Alzheimer disease (AD). However, it remains unknown whether Pen-2 regulates neuronal survival and neuroinflammation in the adult brain. METHODS: Forebrain neuron-specific Pen-2 conditional knockout (Pen-2 cKO) mice were generated for this study. Pen-2 cKO mice expressing Notch1 intracellular domain (NICD) conditionally in cortical neurons were also generated. RESULTS: Loss of Pen-2 causes astrogliosis followed by age-dependent cortical atrophy and neuronal loss. Loss of Pen-2 results in microgliosis and enhanced inflammatory responses in the cortex. Expression of NICD in Pen-2 cKO cortices ameliorates neither neurodegeneration nor neuroinflammation. CONCLUSIONS: Pen-2 is required for neuronal survival in the adult cerebral cortex. The Notch signaling may not be involved in neurodegeneration caused by loss of Pen-2.

15.
Neurobiol Dis ; 148: 105212, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33276084

RESUMO

PDK1 (3-Phosphoinositide dependent protein kinase-1) is a member in the PI3K (phosphatidylinositol 3 kinase) pathway and is implicated in neurodevelopmental disease with microcephaly. Although the role of PDK1 in neurogenesis has been broadly studied, it remains unknown how PDK1 may regulate oligogenesis in the central nervous system (CNS). To address this question, we generated oligodendrocyte (OL) lineage cells specific PDK1 conditional knockout (cKO) mice. We find that PDK1 cKOs display abnormal white matter (WM), massive loss of mature OLs and severe defect in myelination in the CNS. In contrast, these mutants exhibit normal neuronal development and unchanged apoptosis in the CNS. We demonstrate that deletion of PDK1 severely impairs OL differentiation. We show that genetic or pharmacological inhibition of PDK1 causes deficit in the mammalian target of rapamycin (mTor) signaling and down-regulation of Sox10. Together, these results highlight a critical role of PDK1 in OL differentiation during postnatal CNS development.

16.
Zhonghua Nan Ke Xue ; 26(1): 36-41, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33345475

RESUMO

Objective: To investigate the effect of intraoperative lithotomy position (LP) with a head-down tilt (HDT) on the absorption of intraoperative irrigation fluid in patients undergoing bipolar plasmakinetic resection of the prostate (PKRP). METHODS: Eighty BPH patients underwent PKRP, 40 in a conventional 0-degree position (0° LP) and the other 40 in a -10-degree HDT position (-10° LP), with 0.9% saline containing 1% ethanol as intraoperative irrigation fluid. We determined the alcohol concentration in the exhaled breath of the patients with a digital alcohol detector at the start of the operation and every 10 minutes afterwards. Meanwhile we recorded the operation time, the volume of intraoperative intravenous crystalloid infusion and the weight of the resected prostatic tissue, monitored the mean arterial pressure (MAP) and heart rate (HR) at 5 minutes before surgery, 30 minutes after the start of surgery and the end of surgery, and measured the concentrations of Na+, K+, Cl- and Ca2+ with an arterial blood gas analyzer at 5 minutes before surgery and 1 hour after the start of surgery. RESULTS: There were no statistically significant differences in age, height, body weight and prostate volume, or in intraoperative MAP and HR between the 0° LP and -10° LP groups. Compared with the baseline, at 1 hour after the start of PKRP, the patients in the 0° LP group showed significantly decreased concentrations of K+ (ï¼»3.64 ± 0.29ï¼½ vs ï¼»3.49 ± 0.22ï¼½ mmol/L, P = 0.002) and Ca2+ (ï¼»1.16 ± 0.03ï¼½ vs ï¼»1.13 ± 0.04ï¼½ mmol/L, P = 0.001), increased concentration of Cl- (ï¼»106.9 ± 2.2ï¼½ vs ï¼»108.7 ± 2.3ï¼½ mmol/L, P = 0.006), but no significant difference in the concentration of Na+ (ï¼»139.7 ± 1.5ï¼½ vs ï¼»139.4 ± 1.6ï¼½ mmol/L, P = 0.231), while those in the -10° LP group exhibited remarkably decreased concentration of Ca2+ (ï¼»1.14 ± 0.04ï¼½ vs ï¼»1.13 ± 0.04ï¼½ mmol/L, P = 0.016) but no statistically significant differences in the concentrations of Na+ (ï¼»140.3 ± 1.8ï¼½ vs ï¼»140.0 ± 2.0ï¼½ mmol/L, P = 0.156), K+ (ï¼»3.49 ± 0.36ï¼½ vs ï¼»3.47 ± 0.34ï¼½ mmol/L, P = 0.506) and Cl- (ï¼»108.2 ± 2.6ï¼½ vs ï¼»109.1 ± 2.5ï¼½ mmol/L, P = 0.071). Over 1 500 ml of intraoperative irrigation fluid absorption was observed in 6 cases (15%) in the 0° LP group as compared with 4 cases (10%) in the -10°LP group, with no significant difference between the two groups. CONCLUSIONS: Lithotomy position with a 10-degree head-down tilt can reduce PKRP-induced decrease in the concentration of K+ and increase in that of Cl- without affecting the levels of the other electrolytes.


Assuntos
Decúbito Inclinado com Rebaixamento da Cabeça , Posicionamento do Paciente , Hiperplasia Prostática , Ressecção Transuretral da Próstata , Humanos , Masculino , Duração da Cirurgia , Hiperplasia Prostática/cirurgia , Irrigação Terapêutica
17.
Chem Commun (Camb) ; 56(96): 15185-15188, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33216071

RESUMO

A method for the intermolecular annulation of benzynes with allenes is disclosed. This protocol utilized allenes as an unconventional diene component for the selective synthesis of phenanthrenes and dihydrophenanthrenes under the control of different benzyne precursors, featuring high atom-economy and good functional group compatibility. Density functional theory (DFT) calculations reveal that different migratory routes of the aromatic C-H bond are crucial for the observed selectivity.

18.
Langmuir ; 36(35): 10494-10503, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32787020

RESUMO

The influence of the alkyl chain length of the ionic liquid surfactants 1-hexadecyl-3-alkyl imidazolium bromide [C16imCn]Br (n = 2-16) on their aggregation behavior with sodium dodecyl sulfate (SDS) in water was studied. The rheological properties, thermostability, and microstructure of the samples were characterized via a combination of rheology, cryo-transmission electron microscopy, polarization optical microscopy, and small-angle X-ray scattering. Upon the addition of SDS, the [C16imCn]Br (n = 2, 4, 6) rodlike micelles transit into the gels with high water content. The effects of molar ratio and alkyl chain length on the viscoelasticity and thermal stability of the SDS/[C16imCn]Br (n = 2, 4, 6) gels were studied. However, the [C16imCn]Br (n = 8, 10, 12, 14, 16) rodlike micelles precipitate with the addition of SDS. The [C16imCn]Br (n = 10, 12, 14, 16) gels transit to the rodlike micelles with the proper addition of SDS. The mechanism of the influence of the alkyl chain length of the [C16imCn]Br on their aggregation behavior with SDS was proposed.

19.
J Med Chem ; 63(17): 9623-9649, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32787097

RESUMO

The rise of multidrug resistant (MDR) Gram-negative (GN) pathogens and the decline of available antibiotics that can effectively treat these severe infections are a major threat to modern medicine. Developing novel antibiotics against MDR GN pathogens is particularly difficult as compounds have to permeate the GN double membrane, which has very different physicochemical properties, and have to circumvent a plethora of resistance mechanisms such as multiple efflux pumps and target modifications. The bacterial type II topoisomerases DNA gyrase (GyrA2B2) and Topoisomerase IV (ParC2E2) are highly conserved targets across all bacterial species and validated in the clinic by the fluoroquinolones. Dual inhibitors targeting the ATPase domains (GyrB/ParE) of type II topoisomerases can overcome target-based fluoroquinolone resistance. However, few ATPase inhibitors are active against GN pathogens. In this study, we demonstrated a successful strategy to convert a 2-carboxamide substituted azaindole chemical scaffold with only Gram-positive (GP) activity into a novel series with also potent activity against a range of MDR GN pathogens. By systematically fine-tuning the many physicochemical properties, we identified lead compounds such as 17r with a balanced profile showing potent GN activity, high aqueous solubility, and desirable PK features. Moreover, we showed the bactericidal efficacy of 17r using a neutropenic mouse thigh infection model.


Assuntos
Carbolinas/química , Carbolinas/farmacologia , DNA Girase/metabolismo , DNA Topoisomerase IV/metabolismo , Desenho de Fármacos , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , DNA Girase/química , DNA Topoisomerase IV/química , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Escherichia coli/enzimologia , Camundongos , Modelos Moleculares , Conformação Proteica , Staphylococcus aureus/enzimologia
20.
Angew Chem Int Ed Engl ; 59(45): 19820-19824, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32820579

RESUMO

Herein we describe the first organocatalytic asymmetric C(sp2 )-H allylation of racemic trisubstituted allenoates with Morita-Baylis-Hillman (MBH) carbonates to access axially chiral tetrasubstituted allenoates. Various trisubstituted allenoates and MBH carbonates were well tolerated under mild reaction conditions, providing novel chiral tetrasubstituted allenoates with adjacent axial chirality and tertiary carbon stereocenters in high yields with good to excellent diastereoselectivities and enantioselectivities.

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