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1.
BMC Med Genomics ; 17(1): 26, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243290

RESUMO

BACKGROUND: To compare the expression levels of long non-coding RNA (lncRNA) and messenger RNA (mRNA) in pre-receptive endometrium between patients with Polycystic Ovary Syndrome (PCOS)and normal ovulation undergoing in vitro fertilization-embryo transfer (IVF-ET). METHODS: Endometrial tissues were collected with endometrial vacuum curette in pre-receptive phase (3 days after oocytes retrieval) from PCOS and control groups. LncRNAs and mRNAs of endometrium were identified via RNA sequencing and alignments. A subset of 9 differentially expressed lncRNAs and 11 mRNAs were validated by quantitative reverse transcription polymerase chain reaction(qRT-PCR)in 22 PCOS patients and 18 ovulation patients. The function of mRNAs with differential expression patterns were explored using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). RESULTS: We found out 687 up-regulated and 680 down-regulated mRNAs, as well as 345 up-regulated and 63 down-regulated lncRNAs in the PCOS patients in contrast to normal ovulation patients. qRT-PCR was used to detect the expression of 11 mRNAs, and validated that the expression of these 6 mRNAs CXCR4, RABL6, OPN3, SYBU, IDH1, NOP10 were significantly elevated among PCOS patients, and the expression of ZEB1 was significantly decreased. qRT-PCR was performed to detect the expression of 9 lncRNAs, and validated that the expression of these 7 lncRNAs IDH1-AS1, PCAT14, FTX, DANCR, PRKCQ-AS1, SNHG8, TPT1-AS1 were significantly enhanced among PCOS patients. Bioinformatics analysis showed that differentially expressed genes (DEGs) involved KEGG pathway were tyrosine metabolism, PI3K-Akt pathway, metabolic pathway, Jak-STAT pathway, pyruvate metabolism, protein processing in endoplasmic reticulum, oxidative phosphorylation and proteasome. The up-regulation of GO classification was involved in ATP metabolic process, oxidative phosphorylation, RNA catabolic process, and down-regulation of GO classification was response to corticosteroid, steroid hormone, and T cell activation. CONCLUSION: Our results determined the characteristics and expression profile of endometrial lncRNAs and mRNAs in PCOS patients in pre-receptive phase, which is the day 3 after oocytes retrival. The possible pathways and related genes of endometrial receptivity disorders were found, and those lncRNAs may be developed as a predictive biomarker of endometrium in pre-receptive phase.


Assuntos
Síndrome do Ovário Policístico , RNA Longo não Codificante , Humanos , Feminino , RNA Mensageiro/metabolismo , RNA Longo não Codificante/metabolismo , Síndrome do Ovário Policístico/genética , Janus Quinases/genética , Janus Quinases/metabolismo , Fosfatidilinositol 3-Quinases/genética , Transdução de Sinais , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Perfilação da Expressão Gênica , Transferência Embrionária , Endométrio/metabolismo , Fertilização in vitro , Redes Reguladoras de Genes , Opsinas de Bastonetes/genética , Opsinas de Bastonetes/metabolismo
2.
Microbiol Immunol ; 68(1): 6-14, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37985160

RESUMO

Staphylococcus aureus is a common pathogen capable of infecting both humans and animals and causing various severe diseases. Here, we aimed to determine the biological features and pathogenicity of S. aureus strain Sa9, of the incomplete hemolysis phenotype, isolated from bovine milk. Sa9 was classified as ST97 by multilocus sequence typing, and it showed increased ß-hemolysin expression and lower Hla and Hld expression levels compared with that in the S. aureus USA300 strain LAC. RT-PCR and ELISA results showed that the expression levels of inflammatory cytokines were higher in Sa9-induced mouse primary peritoneal macrophages compared with those induced by the LAC strain. However, the Sa9 strain also mediated anti-inflammatory effects by upregulating IL-10 and IFN-ß in macrophages, which were not apparently induced by S. aureus culture supernatants. Phagocytosis and whole-blood survival assays were also performed to assess the in vitro survival of bacteria, and the virulence was evaluated in mice. Although the Sa9 strain showed lower ability of intracellular survival in macrophages than LAC, similar multiplication in human whole blood and pathogenicity toward mice were observed. Taken together, we report that the distinctive immune response induced by the S. aureus strain with an incomplete hemolysis phenotype occurs in cattle, and its potential pathogenicity and risk of transmission to humans require attention.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Bovinos , Humanos , Animais , Camundongos , Staphylococcus aureus/genética , Virulência/genética , Leite , Hemólise , Fenótipo , Infecções Estafilocócicas/microbiologia
3.
J Am Chem Soc ; 145(44): 23899-23904, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37877952

RESUMO

The first oxidative chloro- and bromodifluoromethylation of phenols with (CH3)3SiCF2X and CuX (X = Cl or Br) in the presence of Selectfluor under mild reaction conditions was developed. This protocol provided a practical and efficient method for the synthesis of a diverse range of biologically valuable and synthetically challenging chloro- and bromodifluoromethyl aryl ethers. Preliminary mechanistic studies suggest that this reaction proceeded through a difluorocarbene-involved oxidative coupling process.

4.
Beilstein J Org Chem ; 19: 1372-1378, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37736392

RESUMO

A visible-light-induced nickel-catalyzed cross coupling of alkyl carboxylic acids with N-trifluoroethoxyphthalimide is described. Under purple light irradiation, an α-hydroxytrifluoroethyl radical generated from a photoactive electron donor-acceptor complex between Hantzsch ester and N-trifluoroethoxyphthalimide was subsequently engaged in a nickel-catalyzed coupling reaction with in situ-activated alkyl carboxylic acids. This convenient protocol does not require photocatalysts and metal reductants, providing a straightforward and efficient access to trifluoromethyl alkyl acyloins in good yields with broad substrate compatibility. The complex bioactive molecules were also compatible with this catalytic system to afford the corresponding products.

5.
Asian J Androl ; 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37695244

RESUMO

The sperm DNA fragmentation index (DFI) is a metric used to assess DNA fragmentation within sperm. During in vitro fertilization-embryo transfer (IVF-ET), high sperm DFI can lead to a low fertilization rate, poor embryo development, early miscarriage, etc. A kinase anchoring protein (AKAP) is a scaffold protein that can bind protein kinase A (PKA) to subcellular sites of specific substrates and protects the biophosphorylation reaction. Sperm protein antigen 17 (SPA17) can also bind to AKAP. This study intends to explore the reason for the decreased fertilization rate observed in high sperm DFI (H-DFI) patients during IVF-ET. In addition, the study investigates the expression of AKAP, protein kinase A regulatory subunit (PKARII), and SPA17 between H-DFI and low sperm DFI (L-DFI) patients. SPA17 at the transcriptional level is abnormal, the translational level increases in H-DFI patients, and the expression of AKAP4/PKARII protein decreases. H2O2 has been used to simulate oxidative stress damage to spermatozoa during the formation of sperm DFI. It indicates that H2O2 increases the expression of sperm SPA17 protein and suppresses AKAP4/PKARII protein expression. These processes inhibit sperm capacitation and reduce acrosomal reactions. Embryo culture data and IVF outcomes have been documented. The H-DFI group has a lower fertilization rate. Therefore, the results indicate that the possible causes for the decreased fertilization rate in the H-DFI patients have included loss of sperm AKAP4/PKARII proteins, blocked sperm capacitation, and reduced occurrence of acrosome reaction.

6.
J Org Chem ; 88(7): 4434-4441, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36920884

RESUMO

Due to the unique properties of the OCF3 group, trifluoromethyl ether compounds play an important role in pharmaceuticals and agrochemicals. Recently, considerable attention has been focused on the development of practical and convenient reagents for the direct incorporation of the OCF3 group into organic compounds. Herein, we reported a new trifluoromethoxylating reagent N-trifluoromethoxyphthalimide (Phth-OCF3). The reagent was a stable solid and released an OCF3 anion under mild reaction conditions. We demonstrated the application of Phth-OCF3 for the nucleophilic trifluoromethoxylation of various alkyl electrophiles.

7.
Org Lett ; 25(6): 1035-1039, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36749173

RESUMO

The first hydrofluoromethylation of unactivated alkenes with fluoroiodomethane and hydrosilanes is developed by merging photoredox catalysis and silane-mediated deiodination processes. The key to the success of this reaction is the use of water as the solvent to enhance the activity of CH2F radical toward unactivated alkenes.

8.
Curr Top Med Chem ; 23(14): 1340-1351, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36567287

RESUMO

Drug polymorphism is an important factor affecting the drugs quality and clinical efficacy. Therefore, great attention should be paid to the crystal analysis of drugs with their researching and evaluating part. With the booming development of Raman spectroscopy in recent years, more and more crystal analysis investigations were based on vibrational spectroscopy. This review mainly discussed the qualitative and quantitative analysis of active pharmaceutical ingredients (API) and pharmaceutical preparation with Raman spectroscopy. On basis of the determination of the vibration mode of drug molecules and the analysis of their chemical structure, this method had the advantages of universal, non-destructive, fast determination, low samples and cost, etc. This review provides theoretical and technical support for crystal structure, which are worth popularizing. It is expected that it will be helpful to relevant government management institutions, pharmaceutical scientific research institutions and pharmaceutical manufacturers.


Assuntos
Análise Espectral Raman , Análise Espectral Raman/métodos , Preparações Farmacêuticas
9.
Org Lett ; 24(50): 9332-9336, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36484514

RESUMO

A photochemically induced nickel-catalyzed radical cross-coupling of phthalimido trifluoroethanol with aryl bromides to furnish α-aryl-α-trifluoromethyl alcohols is reported. This reaction proceeds via a photoinduced charge transfer of an electron donor-acceptor complex between Hantzsch ester and phthalimido trifluoroethanol, followed by 1,2-hydrogen atom transfer, to generate the α-hydroxytrifluoroethyl radical for the cross-coupling of aryl bromides. No exogenous photocatalysts or stoichiometric metal reductants are required in this mild and operationally simple protocol. Broad substrate compatibility and excellent functional group tolerance are observed.

10.
Front Endocrinol (Lausanne) ; 13: 915923, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157446

RESUMO

Objective: The aim of this study is to investigate the optimal estradiol (E2) level on the day of gonadotropin-releasing hormone antagonist (GnRH-ant) initiation to maximize the clinical pregnancy rate (CPR) after fresh embryo transfer among patients with simple tubal factor infertility. Methods: A retrospective cohort study was conducted in the Reproductive Medicine Center, the Second Hospital of Hebei Medical University. A total of 1,493 IVF-ET cycles of patients diagnosed with single tubal factor infertility from August 2016 to August 2021 were included and equally allocated into five distinct groups according to the quintile serum E2 levels on the day of GnRH-ant initiation. The five groups had similar baseline data except for antral follicle count. Results: The serum E 2 level on GnRH-ant initiation day was determined as an independent predictor of clinical pregnancy after adjusting for confounding factors such as age, infertility duration, body mass index, cycle number, antral follicle count, and the number of transferred embryos. Through smooth curve fitting, we found that, with the increase of serum E2 levels on the day of GnRH-ant initiation, CPR showed a trend of slight increase and then slight decrease. The maximal CPR was achieved when the serum E2 level on GnRH-ant initiation day was 498 pg/ml. When E2 was less than 498 pg/ml, the odds ratio (OR) of clinical pregnancy was 1.05 (95% CI: 1.00, 1.11, P = 0.0583). When E2 was greater than 498 pg/ml, the OR of clinical pregnancy was 0.97 (95% CI: 0.95, 0.98, P = 0.0003). Furthermore, CPR remained high when E2 was 436.8-658.6 pg/ml but declined significantly by more than 40% when E2 was ≥ 894.4 pg/ml (P < 0.05). Conclusions: The serum E2 level should be considered as an adjuvant parameter for GnRH-ant initiation. The best E2 value was 498 pg/ml, and GnRH-ant administration could be recommended to initiate when serum E2 was 436.8-658.6 pg/ml. If GnRH-ant was initiated when serum E2 was above 894.4 pg/ml, then the CPR after fresh embryo transfer may decline dramatically, and thus, cancellation of fresh embryo transfer and earlier initiation of GnRH-ant in future cycles should be considered.


Assuntos
Fertilização in vitro , Infertilidade , Estradiol , Feminino , Hormônio Liberador de Gonadotropina , Antagonistas de Hormônios/uso terapêutico , Humanos , Gravidez , Estudos Retrospectivos
11.
Cell Biosci ; 12(1): 111, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869560

RESUMO

BACKGROUND: More than 70% of leiomyomas (LM) harbor MED12 mutations, primarily in exon 2 at c.130-131(GG). The cause of MED12 mutations in myometrial cells remains largely unknown. We hypothesized that increased ROS promotes MED12 mutations in myometrial cells through the oxidation of guanine nucleotides followed by misrepair. METHODS: Genomic oxidative burden (8-OHdG) was evaluated in vitro and in vivo by immunohistochemistry. MED12 mutations were examined by Sanger sequencing and deep sequencing. Transcriptome examined by RNA-seq was performed in myometrium with and without LM, in primary myometrial cells treated with ROS. 8-OHdG mediated misrepair was analyzed by CRISPR/Cas9. RESULTS: Uteri with high LM burden had a significantly higher rate of MED12 mutations than uteri with low LM burden. Compelling data suggest that the uterus normally produces reactive oxidative species (ROS) in response to stress, and ROS levels in LM are elevated due to metabolic defects. We demonstrated that genomic oxidized guanine (8-OHdG) was found at a significantly higher level in the myometrium of uteri that had multiple LM compared to myometrium without LM. Transcriptome and pathway analyses detected ROS stress in myometrium with LM. Targeted replacement of guanine with 8-OHdG at MED12 c.130 by CRISPR/Cas9 significantly increased the misrepair of G>T. Exposure of primary myometrial cells to oxidative stress in vitro increased misrepair/mutations as detected by duplex sequencing. CONCLUSIONS: Together, our data identified a clear connection between increased myometrial oxidative stress and a high rate of MED12 mutations that may underlie the risk of LM development and severity in women of reproductive age.

12.
Spectrochim Acta A Mol Biomol Spectrosc ; 278: 121317, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35537260

RESUMO

The traditional Chinese medicine (TCM) extraction process is a complicated dynamic system with many variables and disturbance. Therefore, multi critical quality attributes (CQAs) monitoring is of great significance to understand the whole process. Spectroscopy is a powerful process analytical tool used for process understanding. However, single senor sometimes could not provide comprehensive information. Sensor fusion is a very practical method to overcome this deficiency. In this study, the extraction process of Xiao'er Xiaoji Zhike Oral Liquid (XXZOL) was carried out in pilot scale, where near infrared (NIR) spectroscopy and mid infrared (MIR) spectroscopy were collected to determine the concentrations of seven CQAs (synephrine, arecoline, chlorogenic acid, forsythoside A, naringin, hesperidin and neohesperidin) during extraction process. Based on fused data blocks, fusion partial least squares (PLS) models were established. Two fusion data blocks are obtained from the concatenation of original spectra (low-level data fusion) and the concatenation of characteristic variables based on band selection (mid-level data fusion) respectively. The results indicated that for all seven analytes, the mid-level data fusion models were superior to the single spectral models, with the prediction performance significantly improved. Specifically, the coefficients of determination (Rp2 and Rt2) of NIR, MIR and fusion quantitative models were all higher than 0.95. The relative standard errors of prediction (RSEP) values were all within 10%, except for models of neohesperidin, which were 10.76%, 12.39%, 12.05%, 10.03% for NIR, MIR, low-level and mid-level models respectively. These results demonstrate that it is feasible to monitor the extraction process of Xiao'er Xiaoji Zhike Oral Liquid more accurately and rapidly by fusing NIR and MIR spectroscopy, and the proposed approach also has vital and valuable reference value for the rapid monitoring of the mixed decoction process of other TCM.


Assuntos
Medicamentos de Ervas Chinesas , Espectroscopia de Luz Próxima ao Infravermelho , China , Ácido Clorogênico , Medicamentos de Ervas Chinesas/química , Análise dos Mínimos Quadrados , Medicina Tradicional Chinesa , Espectroscopia de Luz Próxima ao Infravermelho/métodos
13.
Front Endocrinol (Lausanne) ; 13: 798434, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574014

RESUMO

Objective: To evaluate the pregnancy outcomes of progestin-primed ovarian stimulation (PPOS) protocol for patients with endometrioma underwent in vitro fertilization/intra-cytoplasmic sperm injection embryo transfer (IVF/ICSI-ET). Design: Observational retrospective cohort study. Setting: University affiliated reproductive center. Study Participants: 605 infertile patients with endometrioma underwent IVF/ICSI-ET from January 2016 to March 2021 were included in this study. Methods: Multivariable logistic regression analyses were conducted to determine the independent effect of controlled ovarian stimulation (COS) protocols on reproductive outcomes of first embryo transfer (ET) cycles. The live birth was primary outcome, the implantation rate, biochemical pregnancy, clinical pregnancy and ongoing pregnancy were secondary outcomes. Results: Compared to PPOS protocol, the probability of implantation showed no significant difference with ultra-long gonadotrophin-releasing hormone agonist (GnRHa) protocol and gonadotrophin-releasing hormone antagonist (GnRHant) protocol (OR 1.7, 95% CI 0.9-3.1, OR 1.2, 95% CI 0.7-2.1, respectively). The PPOS protocol was correlated with a significantly lower biochemical pregnancy and clinical pregnancy than ultra-long GnRHa protocol in the multivariable logistic regression analysis (OR 2.3, 95% CI 1.1-4.9, OR 2.4, 95% CI 1.1-5.3, respectively). However, there was no significant difference in terms of biochemical pregnancy, clinical pregnancy and ongoing pregnancy between PPOS and GnRHant protocol (OR 1.4, 95% CI 0.7-2.7, OR 1.3, 95% CI 0.7-2.4, OR 1.1, 95% CI 0.6-2.3, respectively). In addition, compared to PPOS protocol, ultra-long GnRHa protocol and GnRHant protocol demonstrated no statistical difference in ongoing pregnancy (OR 2.0, 95% CI 0.9-4.5, OR 2.1, 95% CI 0.6-2.3, respectively). Notably, the ultra-long GnRHa protocol was associated with a significant higher probability of live birth than PPOS protocol both in crude analysis and multivariable logistic regression analysis (OR 2.6, 95% CI 1.3-5.1, OR 2.5, 95% CI 1.1-5.7, respectively). Nevertheless, no statistical difference was found in live birth between PPOS and GnRHant protocol either in crude analysis and multivariable logistic regression analysis (OR1.2, 95% CI 0.6-2.3, OR 1.2, 95% CI 0.6-2.5, respectively). Conclusions: Based on the reproductive outcomes of the first ET cycles in patients with endometrioma, PPOS protocol may associated with inferior reproductive outcomes in terms of biochemical pregnancy, clinical pregnancy and live birth than ultra-long GnRHa protocol. However, there was no significant difference in implantation rate, clinical pregnancy, ongoing pregnancy and live birth between PPOS and GnRHant protocol.


Assuntos
Endometriose , Progestinas , Endometriose/tratamento farmacológico , Feminino , Fertilização in vitro/métodos , Antagonistas de Hormônios , Humanos , Estudos Observacionais como Assunto , Indução da Ovulação/métodos , Gravidez , Estudos Retrospectivos
14.
Cell Death Discov ; 8(1): 118, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292640

RESUMO

The recombinase RAD51 catalyzes the DNA strand exchange reaction in homologous recombination (HR) during both mitosis and meiosis. However, the physiological role of RAD51 during spermatogenesis remains unclear since RAD51 null mutation is embryonic lethal in mice. In this study, we generated a conditional knockout mouse model to study the role of RAD51 in spermatogenesis. Conditional disruption of RAD51 in germ cells by Vasa-Cre led to spermatogonial loss and Sertoli cell-only syndrome. Furthermore, tamoxifen-inducible RAD51 knockout by UBC-CreERT2 confirmed that RAD51 deletion led to early spermatogenic cells loss and apoptosis. Notably, inducible knockout of RAD51 in adult mice caused defects in meiosis, with accumulated meiotic double-strand breaks (DSBs), reduced numbers of pachytene spermatocytes and less crossover formation. Our study revealed an essential role for Rad51 in the maintenance of spermatogonia as well as meiotic progression in mice.

15.
Front Psychiatry ; 13: 828379, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35264988

RESUMO

Background: COVID-19 outbreak have a long-term negative impact on mental health. Meanwhile, it may also provide opportunities for positive outcomes (e.g., post-traumatic growth). Resilience and social support could serve as psychological resources to protect individuals against the detrimental effects of the COVID-19 crisis and enable people to develop positive changes during challenging times. Objective: By testing the roles of resilience and social support in the relationship between COVID-19 related stress and negative mental health outcomes (depression and anxiety), as well as the relationship between COVID-19 related stress and positive mental health outcomes (post-traumatic growth, PTG), this study aimed to investigate the psychological mechanisms involved in different mental health outcomes induced by COVID-19. Methods: An online survey was conducted 1 year after the peak of the COVID-19 outbreak (from April to August 2021) in China. The survey includes demographic questionnaires and six scales: the Impact of Event Scale-Revised for COVID-19 (IES-RC), the 10-item Connor-Davidson Resilience Scale (CD-RISC-10), the Perceived Social Support Scale (PSSS), the Center for Epidemiological Studies Depression Scale (CES-D), the Generalized Anxiety Disorder scale (GAD-7) and the Posttraumatic Growth Inventory (PTGI). The structural equation model (SEM) was used to evaluate the relations and mechanisms between COVID-19 related stress and resilience, social support in depression, anxiety, and PTG. Results: A total of 771 Chinese subjects completed the questionnaire, including 416 (54%) females. COVID-19 related stress was associated with anxiety (P < 0.001), PTG (P < 0.001), and depression (P < 0.001). Resilience was related to depression (P < 0.001), anxiety (P < 0.001), and PTG (P < 0.001). Social support was associated with depression (P < 0.001), anxiety (P < 0.001), and PTG (P < 0.001). Under SEM analysis, resilience mediated the effects of COVID-19 related stress on depression and post-traumatic growth. Social support mediated the impacts of COVID-19 related stress on post-traumatic growth, depression, and anxiety. The path coefficients of the mediation effects were statistically significant. Conclusions: The current findings suggest that COVID-19 related stress has a double-edged effect on mental health. Depression, anxiety, and PTG coexist in Chinese individuals 1 year after the peak of the pandemic. Resilience and social support serve as important protective factors of mental health, safeguard people from the negative mental health outcomes of the COVID-19, and promote PTG.

16.
J Am Chem Soc ; 144(4): 1962-1970, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35045700

RESUMO

N-CF3 compounds constitute valuable targets in medicinal chemistry. Extensive studies have been reported for the preparation of N-CF3 compounds through fluorination and trifluoromethylation of N-containing compounds. The development of new synthetic methods from abundant and easily available substrates is highly desirable but still challenging. Herein, we report the design and synthesis of novel N-Cbz- and N-Boc-N-trifluoromethyl hydroxylamine reagents by silver-mediated oxidative trifluoromethylation. These reagents have been successfully applied to the direct incorporation of a NCF3 moiety into the commonly used unsaturated substrates under photoredox catalysis. This protocol enables the efficient and regioselective C-H trifluoromethylamination of various (hetero)arenes, including complex bioactive molecules. Furthermore, a variety of alkenes, dienes, and isonitriles undergo tandem trifluoromethylamination/functionalization delivering structurally diverse N-trifluoromethyl aliphatic and heteroaromatic amines. Notably, previously unknown cyclic N-CF3 compounds including N-CF3 oxazolidinones and oxazolones were conveniently prepared with N-Boc-N-trifluoromethyl hydroxylamine reagents. Furthermore, diversification of the resulting α-trifluoromethylamino ketones afforded the largely underexplored N-alkenyl- and N-alkynyl-N-CF3 compounds.

17.
Chem Commun (Camb) ; 58(9): 1346-1349, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-34986214

RESUMO

The first C-H trifluoroethylamination of heteroarenes with previously unknown N-trifluoroethyl hydroxylamine reagents was achieved under photoredox catalyzed conditions. In the presence of an iridium(III) photoredox catalyst, a variety of heteroarenes, such as indoles, benzofurans, and benzothiophenes, were smoothly converted to the trifluoroethylaminated products in moderate to high yields and with excellent regioselectivity.

18.
Angew Chem Int Ed Engl ; 61(3): e202114048, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34755434

RESUMO

Trifluoromethoxylated aromatics (ArOCF3 ) are valuable structural motifs in the area of drug discovery due to the enhancement of their desired physicochemical properties upon the introduction of the trifluoromethoxy group (CF3 O). Although significant progress has been made recently in the introduction of CF3 O group into aromatics, current methods either require the use of expensive trifluoromethoxylation reagents or require harsh reaction conditions. We present a conceptually new and operationally simple protocol for the direct C-H trifluoromethoxylation of (hetero)aromatics by the combination of the readily available trifluoromethylating reagent and oxygen under electrochemical reaction conditions. This reaction proceeds through the initial generation of CF3 radical followed by conversion to CF3 O radical, addition to (hetero)aromatics and rearomatization. The utility of this electrochemical trifluoromethoxylation is illustrated by the direct incorporation of CF3 O group into a variety of (hetero)aromatics as well as bio-relevant molecules.

19.
Angew Chem Int Ed Engl ; 60(42): 22915-22924, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34414643

RESUMO

The heptafluoroisopropyl group (CF(CF3 )2 ) is prevalent in pharmaceuticals and agrichemicals. However, heptafluoroisopropoxylated (OCF(CF3 )2 ) compounds remain largely underexplored, presumably due to the lack of efficient access to these compounds. Herein, we disclose the practical and efficient heptafluoroisopropoxylation reactions through the invention of a series of redox-active N-OCF(CF3 )2 reagents. These reagents were readily prepared from the oxidative heptafluoroisopropylation of hydroxylamines with AgCF(CF3 )2 . The substitutions on the nitrogen atom significantly affected the properties and reactivities of N-OCF(CF3 )2 reagents. Accordingly, two types of N-OCF(CF3 )2 reagents including N-OCF(CF3 )2 phthalimide A and N-OCF(CF3 )2 benzotriazolium salt O' were used as OCF(CF3 )2 anion and radical precursors, respectively. This protocol enables the direct heptafluoroisopropoxylation of a range of substrates, delivering the corresponding products in moderate to excellent yields.

20.
Front Nutr ; 8: 696355, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222311

RESUMO

Peanut allergy is becoming a life-threatening disease that could induce severe allergic reactions in modern society, especially for children. The most promising method applied for deallergization is heating pretreatment. However, the mechanism from the view of spectroscopy has not been illustrated. In this study, near-infrared spectroscopy (NIRS) combined with aquaphotomics was introduced to help us understand the detailed structural changes information during the heating process. First, near-infrared (NIR) spectra of Ara h1 were acquired from 25 to 80°C. Then, aquaphotomics processing tools including principal component analysis (PCA), continuous wavelet transform (CWT), and two-dimensional correlation spectroscopy (2D-COS) were utilized for better understanding the thermodynamic changes, secondary structure, and the hydrogen bond network of Ara h1. The results indicated that about 55°C could be a key temperature, which was the structural change point. During the heating process, the hydrogen bond network was destroyed, free water was increased, and the content of protein secondary structure was changed. Moreover, it could reveal the interaction between the water structure and Ara h1 from the perspective of water molecules, and explain the effect of temperature on the Ara h1 structure and hydrogen-bonding system. Thus, this study described a new way to explore the thermodynamic properties of Ara h1 from the perspective of spectroscopy and laid a theoretical foundation for the application of temperature-desensitized protein products.

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