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1.
J Am Chem Soc ; 146(3): 1753-1759, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38193812

RESUMO

Herein, we report the direct carboxylation of unactivated secondary alkyl bromides enabled by the merger of photoredox and nickel catalysis, a previously inaccessible endeavor in the carboxylation arena. Site-selectivity is dictated by a kinetically controlled insertion of CO2 at the initial C(sp3)-Br site by the rapid formation of Ni(I)-alkyl species, thus avoiding undesired ß-hydride elimination and chain-walking processes. Preliminary mechanistic experiments reveal the subtleties of stereoelectronic effects for guiding the reactivity and site-selectivity.

2.
J Am Chem Soc ; 142(38): 16234-16239, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32910658

RESUMO

A remote catalytic reductive sp2 C-H carboxylation of arenes with CO2 (1 bar) via 1,4-Ni migration is disclosed. This protocol constitutes the first catalytic 1,4-Ni migration reported to date, thus offering new vistas in the Ni-catalyzed reductive coupling arena while providing an unconventional new platform for incorporating electrophilic sites at remote sp2 C-H linkages.

3.
Angew Chem Int Ed Engl ; 59(5): 2061-2065, 2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-31742879

RESUMO

A base-catalyzed reaction that enables stereoselective 1,1-silaboration of terminal alkynes is described. This method not only offers a new strategy to functionalize simple and readily accessible alkynes beyond 1,2-difunctionalization, but also provides an unconventional atom- and step-economical approach to rapidly and reliably access versatile geminal silylboranes in the absence of transition metals and with exquisite stereoselectivity.

4.
Angew Chem Int Ed Engl ; 59(11): 4370-4374, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-31910307

RESUMO

A modular, site-selective 1,2-dicarbofunctionalization of vinyl boronates with organic halides through dual catalysis is described. This reaction proceeds under mild conditions and is characterized by excellent chemo- and regioselectivity. It thus represents a complementary new technique for preparing densely functionalized alkyl boron architectures from simple and accessible precursors.

5.
Angew Chem Int Ed Engl ; 57(34): 11035-11039, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-29969531

RESUMO

The functionalization of aminoheterocycles by using a pyrylium tetrafluoroborate reagent (Pyry-BF4 ) is presented. This reagent efficiently condenses with a great variety of heterocyclic amines and primes the C-N bond for nucleophilic aromatic substitution. More than 60 examples for the formation of C-O, C-N, C-S, or C-SO2 R bonds are disclosed herein. In contrast to C-N activation through diazotization and polyalkylation, this method is characterized by its mild conditions and impressive functional-group tolerance. In addition to small-molecule derivatization, Pyry-BF4 allows the introduction of functional groups in a late-stage fashion to furnish highly functionalized structures.

6.
J Org Chem ; 82(15): 8273-8281, 2017 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-28686431

RESUMO

The highly diastereoselective synthesis of CF3-containing vicinal diamines by a convenient two-step procedure without the need to isolate the intermediate products is described.

7.
Glob Med Genet ; 11(2): 159-166, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38638371

RESUMO

Purpose To analyze the factors affecting the mobilization efficiency of hematopoietic stem cells and hematopoietic reconstruction indicators during autologous peripheral hematopoietic stem cell transplantation. Methods The clinical data of 54 patients who underwent autologous peripheral blood hematopoietic stem cell mobilization and transplantation at Xuzhou Central Hospital from May 2016 to April 2023 were retrospectively analyzed. The gender, age, disease type, mobilization regimen, number of chemotherapy sessions, G-CSF (granulocyte colony-stimulating factor) dosage, and platelet number at the time of collection were also collected. Moreover, the relationship between these indicators with mobilization results and hematopoietic reconstruction was analyzed. Results Results showed that age, disease type, and number of collections were significantly related to the mobilization results (number of CD34+ hematopoietic stem cells). Furthermore, multivariate analysis showed that the number of collections was an independent factor affecting mobilization efficiency. Similarly, age, platelet value at the time of collection, CD34+ stem cell value during collection, white blood cell count, and number of chemotherapy times were significantly related to the time of megakaryocytic hematopoietic reconstruction. Multifactor analysis found that age and platelet count were independent factors affecting the reconstruction time of the megakaryocytic system. However, no factor was related to the time of granulocyte hematopoietic reconstruction. Conclusion Platelet count and age when collecting hematopoietic stem cells are closely related to megakaryocytic hematopoietic reconstruction and are key indicators of early hematopoietic reconstruction after autologous hematopoietic stem cell transplantation.

8.
J Cancer Surviv ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970716

RESUMO

PURPOSE: To investigate the potential impact of concurrent aerobic and strength training (CT) on women diagnosed with breast cancer. METHODS: Articles published in English and indexed in the PubMed, Web of Science, SPORTDiscus, The Cochrane Library, PsycINFO, EMBASE, and CINAHL Plus databases from their inception to 12 December 2023 were searched. Eligible studies were randomized controlled trials that involved CT and assessed cardiorespiratory fitness, cancer-related fatigue, and quality of life (QoL) using specialized tools. Subgroup analyses were conducted as per treatment status and characteristics. Risk of bias was evaluated with the Cochrane risk-of-bias tool (RoB 2.0). RESULTS: This study included 29 studies involving 2071 participants. CT was found to significantly improve patients' cardiorespiratory fitness (weighted mean difference = 4.24 mL/kg/min, 95% confidence interval (CI) = 1.93-6.55, P < 0.001), cancer-related fatigue (standardized mean difference (SMD) = - 0.74, 95% CI = - 1.05 to - 0.44, P < 0.001), and QoL (SMD = 0.76, 95% CI = 0.50-1.01, P < 0.001). The analysis of secondary outcomes found that CT could significantly improve patients' body composition, anxiety, pain, sleep disorders, and anorexia and enhance upper and lower limb muscle strength, but was ineffective on depression. CONCLUSION: For women with breast cancer, CT significantly enhances cardiorespiratory fitness, alleviates cancer-related fatigue, and improves QoL. The health benefits of CT are inferior in the postmenopausal cohort compared to the overall study population. IMPLICATIONS FOR CANCER SURVIVORS: CT is advisable for female breast cancer survivors due to its significant effectiveness in mitigating cancer-related fatigue, enhancing cardiorespiratory fitness, and improving the QoL.

9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(4): 1150-1155, 2022 Aug.
Artigo em Zh | MEDLINE | ID: mdl-35981376

RESUMO

OBJECTIVE: To investigate the application effect of sequential autologous hematopoietic stem cell transplantation (Auto-HSCT) with lenalidomide, bortezomib and dexamethasone (RVD) in the treatment of multiple myeloma (MM) evaluated by propensity score matching. METHODS: The clinical data of 49 MM patients treated with RVD scheme and followed-up for 36 months in the hospital from January 2015 to January 2021 were retrospectively analyzed and included in the control group, the clinical data of 54 MM patients who received RVD scheme and sequential Auto-HSCT scheme and completed 36 months of follow-up in the hospital during the same period were collected and included in the observation group. PSM method (1∶1, caliper value=0.01) was used to match the control group with the observation group based on baseline data and laboratory indexes, covariate equilibrium samples were obtained between groups (40 cases in each group). The clinical efficacy of patients in the two groups after 18 weeks of treatment was compared; the incidence of toxic and side effects during treatment of patients in the two groups was compared; the survival of patients in the two groups was compared after 36 months of follow-up. RESULTS: The ORR and DCR in the observation group were higher than those in the control group, the difference was statistically significant (P<0.05). Compared the incidence of fatigue, rash, thrombocytopenia, anemia and nausea of patients in the two groups, there was no statistical significant difference (P>0.05). After 36 months of follow-up (no loss during follow-up), 4 cases died from illness in the observation group, with a survival rate of 90% and an average survival time of 35.61 (95% CI: 35541-35.685) months, 10 cases died from illness in the control group, with a survival rate of 75% and an average survival time of 34.70 (95% CI: 34.559-34.832) months, the survival rate of the observation group was higher than that of the control group, the difference was statistically significant (P<0.05). CONCLUSION: Sequential Auto-HSCT with RVD regimen in the treatment of MM can improve the short-term efficacy and increase the survival rate of patients, which will not increase toxic and side effects and has high safety.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bortezomib/uso terapêutico , Dexametasona , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Mieloma Múltiplo/tratamento farmacológico , Pontuação de Propensão , Estudos Retrospectivos , Transplante Autólogo/métodos , Resultado do Tratamento
10.
Chem Commun (Camb) ; 53(27): 3870-3873, 2017 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-28317978

RESUMO

Difluoroethylsulfonium salt, Ph2S+CH2CF2H OTf-, was developed into a convenient difluoromethylcarbene reagent for the iron-catalyzed cyclopropanation of terminal olefins, giving various difluoromethyl-cyclopropanes with excellent diastereoselectivities and in high yields.

11.
Org Lett ; 18(10): 2471-4, 2016 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-27169696

RESUMO

The trifluoromethylcarbene (:CHCF3) was found to be conveniently generated from (2,2,2-trifluoroethyl)diphenyl-sulfonium triflate (Ph2S(+)CH2CF3 (-)OTf), which was successfully applied in Fe-catalyzed cyclopropanation of olefins, giving the corresponding trifluoromethylated cyclopropanes in high yields.

12.
Chem Commun (Camb) ; 51(66): 13127-30, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26189644

RESUMO

(2,2,2-Trifluoroethyl)diphenylsulfonium triflate was found to be an efficient ylide reagent for the Johnson-Corey-Chaykovsky reaction to afford trifluoromethyl epoxides, cyclopropanes and aziridines. Interestingly, excellent but different diastereoselectivity was observed for these transformations. Both trifluoromethyl epoxides and cyclopropanes were obtained with trans-selectivity, whereas aziridines were obtained with cis-selectivity.


Assuntos
Hidrocarbonetos Fluorados/química , Aziridinas/química , Ciclopropanos/química , Compostos de Epóxi/química , Estereoisomerismo
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