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1.
Talanta ; 236: 122877, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635257

RESUMO

A covalent organic framework (named as TpDq) linked by ß-ketoamine was prepared by imine condensation reaction with 1,3,5-triformylphloroglucinol (TFP) and 2,6-diaminoanthraquinone (DAAQ) as building blocks. Via employing a functionalized modification strategy, a new lanthanide complex Eu3+-ß-diketone functionalized covalent organic framework hybrid material, Eu-TTA@TpDq (TTA = 2-thenoyltrifluoroacetone), has been synthesized. After post-synthetic modification (PSM), the shape and structure of the parent framework is well preserved and the modified material shows remarkable luminescence properties. Based on this, we designed it as a fluorescent probe and tried to use it to sense common aldehydes. The results indicate that Eu-TTA@TpDq exhibits a turn-off response toward glutaraldehyde which can distinguish from other common aldehydes. The fluorescent probe has the advantages of reusability, pH stability (4.50-8.52), fast luminescence response (<1 min) and low detection limit. The linear range of this method was 0-100 µM; the detection limit was 4.55 µM; the relative standard deviation was 2.16%. Furthermore, it has broad application prospect in both practical sensing of glutaraldehyde in water environment and simple detection of glutaraldehyde vapor. In addition, we preliminarily discussed the possible sensing mechanism.


Assuntos
Elementos da Série dos Lantanídeos , Estruturas Metalorgânicas , Glutaral , Cetonas , Luminescência
2.
Anticancer Res ; 41(10): 5007-5014, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34593449

RESUMO

BACKGROUND/AIM: In our previous study, first-line eribulin (ERI) showed 25 weeks of progression-free survival (PFS). This study investigated the efficacy and safety of ERI re-administration in metastatic breast cancer (MBC) patients. PATIENTS AND METHODS: HER2-negative MBC patients who had never received chemotherapy for MBC received first-line ERI for 18 weeks if they did not have disease progression, and then one cycle of S-1 before ERI re-administration. RESULTS: Twelve patients received ERI re-administration. The PFS of re-administered ERI was 13 weeks. Total duration of ERI use was 30 weeks. The incidence and severity of adverse events were consistent with previous reports. CONCLUSION: In the first-line setting, the total PFS of eribulin was extended by S-1 administration before disease progression, compared with that of our previous report.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Receptor ErbB-2/metabolismo , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Furanos/administração & dosagem , Humanos , Cetonas/administração & dosagem , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Prognóstico , Retratamento , Taxa de Sobrevida
3.
Nat Commun ; 12(1): 5563, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34548479

RESUMO

Immune checkpoint inhibitors (ICIs) have minimal therapeutic effect in hormone receptor-positive (HR+ ) breast cancer. We present final overall survival (OS) results (n = 88) from a randomized phase 2 trial of eribulin ± pembrolizumab for patients with metastatic HR+ breast cancer, computationally dissect genomic and/or transcriptomic data from pre-treatment tumors (n = 52) for molecular associations with efficacy, and identify cytokine changes differentiating response and ICI-related toxicity (n = 58). Despite no improvement in OS with combination therapy (hazard ratio 0.95, 95% CI 0.59-1.55, p = 0.84), immune infiltration and antigen presentation distinguished responding tumors, while tumor heterogeneity and estrogen signaling independently associated with resistance. Moreover, patients with ICI-related toxicity had lower levels of immunoregulatory cytokines. Broadly, we establish a framework for ICI response in HR+ breast cancer that warrants diagnostic and therapeutic validation. ClinicalTrials.gov Registration: NCT03051659.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Furanos/uso terapêutico , Cetonas/uso terapêutico , Adulto , Idoso , Apresentação do Antígeno/genética , Antígeno B7-H1/metabolismo , Neoplasias da Mama/imunologia , Neoplasias da Mama/mortalidade , Citocinas/sangue , Citocinas/imunologia , Resistencia a Medicamentos Antineoplásicos/genética , Estrogênios/metabolismo , Feminino , Perfilação da Expressão Gênica , Heterogeneidade Genética , Genoma Humano/genética , Genômica , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Linfócitos do Interstício Tumoral/imunologia , Masculino , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Transdução de Sinais/genética , Taxa de Sobrevida , Resultado do Tratamento
4.
Mater Sci Eng C Mater Biol Appl ; 128: 112333, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474884

RESUMO

Polyetheretherketone (PEEK) was widely applied into fabricating of orthopaedic implants, benefitting its excellent biocompatibility and similar mechanical properties to native bones. However, the inertness of PEEK hinders its integration with the surrounding bone tissue. Here PEEK scaffolds with a series of hydroxyapatite (HA) contents in gradient were manufactured via fused filament fabrication (FFF) 3D printing techniques. The influence of the pore size, HA content and printing direction on the mechanical properties of the PEEK/HA scaffolds was systematically evaluated. By adjusting the pore size and HA contents, the elastic modulus of the PEEK/HA scaffolds can be widely tuned in the range of 624.7-50.6 MPa, similar to the variation range of natural cancellous bone. Meanwhile, the scaffolds exhibited higher Young's modulus and lower compressive strength along Z printing direction. The mapping relationship among geometric parameters, HA content, printing direction and mechanical properties was established, which gave more accurate predictions and controllability of the modulus and strength of scaffolds. The PEEK/HA scaffolds with the micro-structured surface could promote cell attachment and mineralization in vitro. Therefore, the FFF-printed PEEK/HA composites scaffolds can be a good candidate for bone grafting and tissue engineering.


Assuntos
Durapatita , Cetonas , Benzofenonas , Polietilenoglicóis , Polímeros , Porosidade , Impressão Tridimensional , Tecidos Suporte
5.
Int J Mol Sci ; 22(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34576025

RESUMO

Aziridination reactions represent a powerful tool in aziridine synthesis. Significant progress has been achieved in this field in the last decades, whereas highly functionalized aziridines including 3-arylated aziridine-2-carbonyl compounds play an important role in both medical and synthetic chemistry. For the reasons listed, in the current review we have focused on the ways to obtain 3-arylated aziridines and on the recent advances (mainly since the year 2000) in the methodology of the synthesis of these compounds via aziridination.


Assuntos
Aziridinas/química , Cetonas/química , Aziridinas/síntese química , Ácidos Carboxílicos/química , Iminas/química , Estrutura Molecular , Estereoisomerismo
6.
J Org Chem ; 86(18): 13025-13040, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34498466

RESUMO

N-Quaternized ketene N,O-acetals are typically an unstable, transient class of compounds most commonly observed as reactive intermediates. In this report, we describe a general synthetic approach to a variety of bench-stable N-quaternized ketene N,O-acetals via treatment of pyridine or aniline bases with acetylenic ethers and an appropriate Brønsted or Lewis acid (triflic acid, triflimide, or scandium(III) triflate). The resulting pyridinium and anilinium salts can be used as reagents or synthetic intermediates in multiple reaction types. For example, N-(1-ethoxyvinyl)pyridinium or anilinium salts can thermally release highly reactive O-ethyl ketenium ions for use in acid catalyst-free electrophilic aromatic substitutions. N-(1-Ethoxyvinyl)-2-halopyridinium salts can be employed in peptide couplings as a derivative of Mukaiyama reagents or react with amines in nucleophilic aromatic substitutions under mild conditions. These preliminary reactions illustrate the broad potential of these currently understudied compounds in organic synthesis.


Assuntos
Acetais , Cetonas , Técnicas de Química Sintética , Etilenos , Indicadores e Reagentes
7.
J Org Chem ; 86(19): 13808-13816, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34514785

RESUMO

The radical 1,5-chloropentafluorosulfanylation of vinyl cyclopropanes (VCPs) initiated by Et3B/O2 affords allylic pentafluorosulfanyl/homoallylic chloride products through the ring-strain release of the cyclopropane. The VCP substitution pattern was investigated. The utility of this reaction was illustrated in post-transformation of the C═C bond by ozonolysis, giving access to valuable α-SF5 carbonyl compounds.


Assuntos
Cetonas
8.
J Org Chem ; 86(19): 13734-13743, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34541847

RESUMO

An efficient, facile, and eco-friendly synthesis of pyrimidine derivatives has been developed. It involves a [3 + 2 + 1] three-component annulation of amidines, ketones, and one carbon source. N,N-Dimethylaminoethanol is oxidized through C(sp3)-H activation to provide the carbon donor. One C-C and two C-N bonds are formed during the oxidative annulation process. The reaction shows good tolerance to many important functional groups in air, making this methodology a highly versatile alternative, and significant improvement to the existing methods for structuring a pyrimidine framework, especially 4-aliphatic pyrimidines.


Assuntos
Amidinas , Cetonas , Carbono , Catálise , Deanol , Pirimidinas
9.
J Org Chem ; 86(19): 13744-13753, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34546055

RESUMO

A novel methodology for the synthesis of 1,5-diketones through a one-pot isomerization-methylenation of a variety of allylic alcohols has been established for the first time. This methodology utilizes commercially available palladium acetate and easily accessible BINOL phosphoric acid. Both isomerization of allylic alcohol and oxidation of methanol occurred through a single catalyst. The practical utility of the methodology has been shown by synthesizing substituted pyridines via sequential addition. Mechanistic investigation reveals the isomerization of allylic alcohols to the corresponding ketone, which ultimately undergoes methylenation, leading to 1,5-diketones, having H2 and H2O as the only byproduct.


Assuntos
Paládio , Propanóis , Isomerismo , Cetonas
10.
J Org Chem ; 86(19): 13783-13789, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34547204

RESUMO

We describe a simple and efficient procedure for the synthesis of N-vinyl-substituted pyridones from ketones and 2-fluoropyridine in the presence of trifluoromethane sulfonic anhydride, followed by a base treatment. Various ketones with electron-donating or electron-withdrawing groups at the benzene rings can be used in this reaction. A preliminary mechanistic study indicates that it is not very likely that both vinyl triflates and vinyl cations play major roles as intermediates in this transformation.


Assuntos
Cetonas , Piridinas , Piridonas
11.
Molecules ; 26(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34500600

RESUMO

Carbon-carbon bond forming reactions, such as aldol reaction and condensation, belong to extremely desired transformations as manifested by >25,000 entries in SciFinder. Their stereoselective variant requires the use of an appropriate catalyst with a strictly defined structure. Hence, chiral 2-azabicycloalkane-based catalysts were designed, synthesized and tested in a stereoselective aldol reaction between cyclic/acyclic ketone and p-nitrobenzaldehyde both in organic and aqueous media. Among catalysts containing a chiral bicyclic backbone, amide based on 2-azabicyclo[3.2.1]octane and pyrrolidine units showed the best catalytic activity and afforded aldol product in excellent chemical yields (up to 95%) and good diastereo- and enantioselectivity (dr 22:78, ee up to 63%).


Assuntos
Aminoácidos/química , Cicloparafinas/química , Poliaminas/química , Amidas/química , Carbono/química , Catálise , Cetonas/química , Pirrolidinas/química , Estereoisomerismo
12.
Aerosp Med Hum Perform ; 92(7): 556-562, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34503629

RESUMO

BACKGROUND: During hypoxia an operators cognitive performance may decline. This decline is linked to altered brain metabolism, resulting in decreased adenosine triphosphate (ATP) production. Ketone bodies are an alternative substrate to glucose for brain metabolic requirements; previous studies have shown that the presence of elevated ketone bodies in the blood maintains brain ATP levels and reduces cerebral glycolysis during hypoxia. Thus, ketones may be a strategy to mitigate cognitive decline in hypoxia. Ketone ester (KE) consumption allows rapid elevation of blood ketone levels; therefore, we investigated the effects of consuming a KE drink on cognitive performance during hypoxia. Here, we report results of a pilot study.METHODS: There were 11 subjects who completed a cognitive performance test battery under conditions of normoxia and hypoxia following consumption of a KE drink and a placebo control drink.RESULTS: Significant hypoxia effects (O2 saturation minimum was found to range between 63 and 88 in subjects) were found for blink duration (Ph2 0.665) and blink rate (Ph2 0.626), indicating that the hypoxia condition was associated with longer blink durations and lower blink rates. Significant hypoxia effects were likewise observed for a code substitution task (Ph2 0.487), indicating that performance on the task was significantly disrupted by the hypoxia stressor. KE consumption had a significant effect on blink duration (Ph2 0.270) and the code substitution task (Ph2 0.309).DISCUSSION: These finding suggest that some effects of acute hypoxia can be mitigated by nutritional ketosis.Coleman K, Phillips J, Sciarini M, Stubbs B, Jackson O, Kernagis D. A metabolic intervention for improving human cognitive performance during hypoxia. Aerosp Med Hum Perform. 2021; 92(7):556562.


Assuntos
Cetose , Cognição , Humanos , Hipóxia , Cetonas , Projetos Piloto
13.
Food Res Int ; 147: 110559, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399536

RESUMO

Aldehydes and ketones are secondary oxidation products resulting from lipid oxidation that occurs during food processing. These small molecule compounds not only have an impact on the quality, odor and flavor of food, but also play a role in the pathogenesis of many human diseases. In this study, a HPLC-MS/MS analytical method was developed and validated for the simultaneous determination of 24 aldehydes and ketones. The coefficients of determination (R2) for all aldehydes and ketones were higher than 0.9975 at the range of 0.2-2000 ng/mL. The recoveries were in the range 71.20-108.13% with RSD < 10%. The method was tested by analyzing lipids from oysters with different thermal processing (boiling, frying, roasting and air frying) procedures; the highest concentration for saturated aldehydes and ketones while the highest content of unsaturated aldehydes in boiling treatment. Meanwhile, fatty acid oxidative decomposition was in agreement with aldehydes and ketones formation. Moreover, principal component analysis, orthogonal partial least-squares discriminant analysis and variable importance in projection value showed that lipid oxidation is positively related to the formation of a variety of aldehydes and ketones.


Assuntos
Aldeídos , Crassostrea , Animais , Cromatografia Líquida de Alta Pressão , Humanos , Cetonas , Espectrometria de Massas em Tandem
14.
Int J Mol Sci ; 22(16)2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34445749

RESUMO

Cigarette smoking and alcohol consumption are major risk factors for lifestyle-related diseases. Although it has been reported that the combination of these habits worsens risks, the underlying mechanism remains elusive. Reactive carbonyl species (RCS) cause chemical modifications of biological molecules, leading to alterations in cellular signaling pathways, and total RCS levels have been used as a lipid peroxidation marker linked to lifestyle-related diseases. In this study, at least 41 types of RCS were identified in the lipophilic fraction of plasma samples from 40 subjects using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS). Higher levels of 10 alkanals, 5 trans-2-alkenals, 1 cis-4-alkenal, and 3 alkadienals were detected in the smoking/drinking group (N = 10) as compared to those with either habit (N = 10 each) or without both habits (N = 10) in the analysis of covariances adjusted for age and BMI. The levels of 3 alkanals, 1 trans-2-alkenal, 1 alkadienal, and 1 4-hydroxy-2-alkenal in the smoking/drinking group were significantly higher than those in the no-smoking/drinking and no-smoking/no-drinking groups. These results strongly indicate that the combination of cigarette smoking and alcohol drinking synergistically increases the level and variety of RCS in the circulating blood, and may further jeopardize cellular function.


Assuntos
Consumo de Bebidas Alcoólicas/sangue , Aldeídos/sangue , Fumar Cigarros/sangue , Cetonas/sangue , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/efeitos adversos , Cromatografia Líquida , Fumar Cigarros/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Carbonilação Proteica , Espectrometria de Massas por Ionização por Electrospray
15.
FASEB J ; 35(9): e21861, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34416029

RESUMO

Duchenne muscular dystrophy (DMD) is an intractable genetic disease associated with progressive skeletal muscle weakness and degeneration. Recently, it was reported that intraperitoneal injections of ketone bodies partially ameliorated muscular dystrophy by increasing satellite cell (SC) proliferation. Here, we evaluated whether a ketogenic diet (KD) with medium-chain triglycerides (MCT-KD) could alter genetically mutated DMD in model rats. We found that the MCT-KD significantly increased muscle strength and fiber diameter in these rats. The MCT-KD significantly suppressed the key features of DMD, namely, muscle necrosis, inflammation, and subsequent fibrosis. Immunocytochemical analysis revealed that the MCT-KD promoted the proliferation of muscle SCs, suggesting enhanced muscle regeneration. The muscle strength of DMD model rats fed with MCT-KD was significantly improved even at the age of 9 months. Our findings suggested that the MCT-KD ameliorates muscular dystrophy by inhibiting myonecrosis and promoting the proliferation of muscle SCs. As far as we can ascertain, this is the first study to apply a functional diet as therapy for DMD in experimental animals. Further studies are needed to elucidate the underlying mechanisms of the MCT-KD-induced improvement of DMD.


Assuntos
Dieta Cetogênica , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Distrofia Muscular de Duchenne/dietoterapia , Distrofia Muscular de Duchenne/fisiopatologia , Triglicerídeos/química , Triglicerídeos/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Fibrose/dietoterapia , Fibrose/patologia , Inflamação/dietoterapia , Inflamação/patologia , Cetonas/sangue , Cetose , Masculino , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Distrofia Muscular de Duchenne/patologia , Necrose/dietoterapia , Necrose/patologia , Ratos , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/efeitos dos fármacos , Triglicerídeos/uso terapêutico
16.
J Phys Chem B ; 125(33): 9588-9600, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34383510

RESUMO

To investigate the damping characteristics of poly(ether ether ketone) (PEEK), various potential modifications of the molecular structure, including sulfonate groups, hydroxyl groups, amino groups, carboxyl groups, methyl groups, fluorines, and benzene rings, were considered. It was found that these functional groups can mediate both the storage and loss modulus of PEEK derivatives, and the loss factors of PEEK derivatives are sensitive to the content and type of functional groups, indicating an ideal designability of energy dissipation performance. The reciprocating process of H-bonds and Cπ-H bonds breaking and reforming during material deformation and the available free volume in the material are critical to the energy dissipation capacities in polymers.


Assuntos
Éter , Cetonas , Éteres , Estrutura Molecular , Polietilenoglicóis , Polímeros
17.
J Phys Chem B ; 125(33): 9579-9587, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34402620

RESUMO

Molecular self-assembly through noncovalent interactions is a particularly efficient approach to fine-tune the optoelectronic and photophysical properties of electroactive materials. In metal-ligand coordination polymers, the final properties of the assemblies are directly related to the nature of the metal-ligand interaction. To probe for such influence on the photophysical properties of electroactive materials, a series of coordination polymers based on a well-known organic dye, diketopyrrolopyrrole, was prepared through coordination of a terpyridine-containing monomer with various metal sources, including iron, cobalt, zinc, and manganese. The resulting supramolecular polymers were characterized through multiple techniques, including UV-vis and fluorescence spectroscopy, time-correlated single-photon counting, and femtosecond transient absorption spectroscopy to reveal the impact of the metal source on the final photophysical properties of coordination polymers. As expected, important variations were found between different coordination polymers in terms of absorption, fluorescence kinetics, and electron transfer rate. While iron and cobalt-containing polymers showed ultrafast electrons transfer rates, assemblies from manganese were shown to be much less efficient, confirming the importance of metal centers. This detailed fundamental study unravels some important relationships between metal-ligand interactions, supramolecular self-assembly, and photophysical properties, ultimately leading to new avenues for the design of functional polymers based on organic dyes.


Assuntos
Elétrons , Polímeros , Cetonas , Metais , Pirróis , Zinco
18.
Chemistry ; 27(57): 14240-14249, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34337810

RESUMO

Organic small-molecule fluorophores with near-infrared IIa (NIR-IIa) emission have great potential in pre-clinical detection and inoperative imaging due to the high-spatial resolution and deep penetration. However, developments of the NIR-IIa fluorophores are still facing considerable challenges. In this work, a series of diketopyrrolopyrrole (DPP)-based fluorophores were designed and synthesized. Subsequently, nanomaterial T25@F127 with significant NIR-IIa emission properties was rationally prepared by encapsulating DPP-based fluorophore T25, and was selected for fluorescence angiography and cerebral vascular microscopic imaging with nearly 800 µm penetrating depth and excellent signal-background ratio of 4.07 and 2.26 (at 250 and 400 µm), respectively. Furthermore, the nanomaterial T25@cRGD with tumor targeting ability can image tiny metastatic tumor on intestine with a small size of 0.3 mm×1.0 mm and high-spatial resolution (SBR=3.84). This study demonstrates that the nanomaterials which encapsulated T25 behave as excellent NIR-IIa fluorescence imaging agents and have a great potential for in vivo biological application.


Assuntos
Corantes Fluorescentes , Imagem Óptica , Cetonas , Pirróis
19.
J Org Chem ; 86(17): 11948-11959, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34351744

RESUMO

(+)-Panamonon B was synthesized with the key quaternary center (of a predefined absolute configuration) installed using Stoltz asymmetric allylation. The C-5 ketone functionality and the cross-conjugated enone moiety in the side chain were introduced via a photosensitized [2+4] cycloaddition of singlet oxygen to diene silyl enol ether and an aldol condensation under the conditions of Sugiura, respectively. The 1H and 13C NMR of the synthetic and natural samples were fully consistent with each other. However, because two samples showed opposite signs for optical rotations, they must be antipodes to one another. The synthesis also provided valuable chances to observe unexpected, yet rather intriguing, phenomena such as a bulky substituent in an axial position of a cyclohexane ring and (E)-and (Z)-isomers with opposite signs for optical rotations despite their identical stereogenic centers. The rare occurrence of a bulky substituent in an axial position of a cyclohexane ring is rationalized as a consequence of the presence of a quaternary center and formation of the five-membered lactone fused to the six-membered ring, while the so far unnoticed influence of C═C geometry on optical rotation is shown to be consistent with the information encapsulated in several discrete pairs of similar compounds retrieved from the literature.


Assuntos
Cetonas , Lactonas , Reação de Cicloadição , Isomerismo , Estereoisomerismo
20.
J Org Chem ; 86(17): 11884-11894, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34387502

RESUMO

ß-Silyl-γ-ethylidene-γ-butyrolactone upon one-pot treatment with aldehydes and ketones in the presence of Lewis acids underwent a tandem Hosomi-Sakurai/Prins cyclization to give polysubstituted tetrahydropyranones stereoselectively. Various aldehydes and ketones can be used in this reaction to produce the corresponding tetrahydropyranones. The optical purity of the starting γ-butyrolactone was substantially retained in the resulting tetrahydropyranones.


Assuntos
Aldeídos , Cetonas , 4-Butirolactona , Ciclização , Ácidos de Lewis , Estereoisomerismo
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