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3.
Int Immunopharmacol ; 130: 111761, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38422769

RESUMEN

The chimeric antigen receptor T (CAR-T) cell therapy significantly enhances the prognosis of various hematologic malignancies; however, the systemic expansion of CAR-T cells also gives rise to severe cytokine release syndrome (CRS), and immune effector cell-associated neurotoxicity syndrome (ICANS). Despite the successful application of corticosteroids and tocilizumab in alleviating severe CRS in most patients, there are still individuals who experience life-threatening CRS without responding to the aforementioned therapies. In our retrospective cohort, we conducted an analysis of clinical and laboratory parameters, including inflammatory cytokines, in 17 patients from three centers who underwent therapeutic plasma exchange (TPE) for refractory CRS with or without ICANS following CAR-T products treatment. Our findings demonstrate a significant improvement in both clinical symptoms and laboratory parameters subsequent to TPE treatment. The rapid decrease in temperature and levels of inflammatory indexes indicates the remarkable scavenging efficacy of TPE against cytokine storm following CAR-T therapy. In conclusion, TPE may serve as a valuable and safe adjunct to corticosteroids and tocilizumab in the management of severe CRS resulting from CAR-T cell infusion. We eagerly await further prospective studies to validate this finding.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Síndromes de Neurotoxicidad , Receptores Quiméricos de Antígenos , Humanos , Síndrome de Liberación de Citoquinas/terapia , Síndrome de Liberación de Citoquinas/tratamiento farmacológico , Receptores de Antígenos de Linfocitos T , Intercambio Plasmático , Estudios Prospectivos , Estudios Retrospectivos , Inmunoterapia Adoptiva/métodos , Síndromes de Neurotoxicidad/tratamiento farmacológico , Corticoesteroides/uso terapéutico
4.
Ann Hematol ; 103(3): 969-980, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38214708

RESUMEN

Chimeric antigen receptor T (CAR-T) cell therapy targeting CLL1 has been considered a potent weapon for patients with acute myeloid leukemia (AML). This study aims to evaluate the efficacy and toxicity of CLL1 CAR-T cell therapy in a larger cohort, with particular attention to cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Among the 32 patients assessed for efficacy, complete remission occurred in 71.88% (23/32) of cases and undetectable minimal residual disease in 14 patients. The CRS developed in all patients, with 8 individuals experiencing ICANS. Severe CRS and ICANS were observed in 11 and 2 patients, respectively. Furthermore, the Endothelial Activation and Stress Index (EASIX) and its derivatives measured before and after CLL1 CAR-T cell infusion were employed for predicting the severe complications. Significant differences were observed in EASIX scores on the day before lymphodepletion (Day BL, P = 0.023), -1 (P < 0.001), +1 (P < 0.001), and +3(P = 0.014); sEASIX scores on Day BL (P = 0.007), -1 (P < 0.001), +1 (P < 0.001), and +3 (P < 0.001); and mEASIX score on Day -1 (P = 0.004) between patients with mild and severe CRS/ICANS. Additionally, there was a significant difference in mEASIX scores between responders and non-responders on Day BL (P = 0.004) and Day -1 (P = 0.044). Our findings indicate that pre- and post-infusion assessments of EASIX/mEASIX/sEASIX scores serve as reliable prognostic indicators for severe CRS/ICANS and treatment response following CLL1 CAR-T cell therapy, which can assist physicians in implementing preemptive treatment strategies for potential severe complications and screening patients who are suitable candidates for CLL1 CAR-T cell therapy. EASIX/mEASIX/sEASIX scores serve as reliable prognostic indicators for severe CRS/ICANS following CLL1 CAR-T cell therapy. The preinfusion mEASIX scores of CLL1 CAR-T cells can effectively predict treatment response.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes de Neurotoxicidad , Receptores Quiméricos de Antígenos , Humanos , Síndrome de Liberación de Citoquinas , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Tratamiento Basado en Trasplante de Células y Tejidos
5.
Nat Chem ; 16(2): 269-276, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37783725

RESUMEN

1,2-Azaborines represent a unique class of benzene isosteres that have attracted interest for developing pharmaceuticals with better potency and bioavailability. However, it remains a long-standing challenge to prepare monocyclic 1,2-azaborines, particularly multi-substituted ones, in an efficient and modular manner. Here we report a straightforward method to directly access diverse multi-substituted 1,2-azaborines from readily available cyclopropyl imines/ketones and dibromoboranes under relatively mild conditions. The reaction is scalable, shows a broad substrate scope, and tolerates a range of functional groups. The utility of this method is demonstrated in the concise syntheses of BN isosteres of a PD-1/PD-L1 inhibitor and pyrethroid insecticide, bifenthrin. Combined experimental and computational mechanistic studies suggest that the reaction pathway involves boron-mediated cyclopropane ring-opening and base-mediated elimination, followed by an unusual low-barrier 6π-electrocyclization accelerated by the BN/CC isomerism. This method is anticipated to find applications for the synthesis of BN-isostere analogues in medicinal chemistry, and the mechanistic insights gained here may guide developing other boron-mediated electrocyclizations.

6.
Angew Chem Int Ed Engl ; 62(48): e202312633, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37822069

RESUMEN

The incorporation of two distinct boryl groups at the same carbon center in organic molecules has attracted growing research interest due to its potential for facilitating controlled, precise synthesis through stepwise dual carbon-boron bond transformations. Here we report a method to access unsymmetrical 1,1-diborylalkene (UDBA) stereoselectively via the reaction of readily available alkynes with a neutral sp2 -sp3 diboron reagent (NHC)BH2 -Bpin (NHC=N-heterocyclic carbene). Attributing to the chemically easily distinguishable nature of the sp2 and sp3 boryl moieties, controllable stepwise derivatization of the resultant UDBAs is realized. This process leads to various multifunctionalized olefins and organoborons, such as acylboranes, which are difficult to prepare by other methods.

7.
Cytotherapy ; 25(9): 903-912, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37149797

RESUMEN

Epstein‒Barr virus (EBV) is a human herpes virus that is saliva-transmissible and universally asymptomatic. It has been confirmed that more than 90% of the population is latently infected with EBV for life. EBV can cause a variety of related cancers, such as nasopharyngeal carcinoma, diffuse large B-cell lymphoma, and Burkitt lymphoma. Currently, many clinical studies have demonstrated that EBV-specific cytotoxic T lymphocytes and other cell therapies can be safely and effectively transfused to prevent and treat some diseases caused by EBV. This review will mainly focus on discussing EBV-specific cytotoxic T lymphocytes and will touch on therapeutic EBV vaccines and chimeric antigen receptor T-cell therapy briefly.


Asunto(s)
Linfoma de Burkitt , Infecciones por Virus de Epstein-Barr , Humanos , Herpesvirus Humano 4 , Linfoma de Burkitt/terapia , Linfocitos T Citotóxicos , Inmunoterapia
8.
Front Immunol ; 14: 1139559, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36999027

RESUMEN

Introduction: Hematologic toxicity (HT) is a joint adverse event after CAR-T cells infusion. Some patients experience prolonged hematologic toxicity (PHT), which is challenging to treat. Methods: We collected clinical data from patients with relapsed refractory B-ALL treated with CD19 CAR-T cells. Patients with PHT who did not respond to erythropoietin, platelet receptor agonists, transfusion, or G-CSF and eventually received low-dose prednisone therapy were included in the analysis. We retrospectively analyzed the efficacy and safety of low-dose prednisone on PHT. Results: Among 109 patients treated with CD19 CAR-T cells, 78.9% (86/109) of patients were evaluated as PHT. Of these, 15 patients had persistent hematological toxicity after infusion (12 were grade 3/4 cytopenia, 12 were trilineage cytopenia and 3 were bilineage cytopenia), 2 developed cytopenia without apparent cause after D28. The initial prednisone dose was 0.5 mg/kg/day, and the median response time was 21 days (7-40 days). The recovery rate of blood count was 100%, and the complete recovery rate ranged from 60% to 66.67%. Especially exciting was that HT recurred in 6 patients after stopping prednisone. They were relieved again after the administration of prednisone. The median follow-up time was 14.97 months (4.1-31.2 months). Twelve-month duration of PFS and OS rates were 58.8% (±11.9%) and 64.7% (±11.6%). We did not observe any other side effects of prednisone apart from drug-controllable hyperglycemia and hypertension. Discussion: We suggest that low-dose prednisone is a beneficial and tolerable therapy for PHT after CAR-T cells. The trials have been registered at www.chictr.org.cn as ChiCTR-ONN-16009862 (November 14, 2016) and ChiCTR1800015164 (March 11, 2018).


Asunto(s)
Receptores Quiméricos de Antígenos , Humanos , Prednisona/efectos adversos , Estudios Retrospectivos , Recurrencia Local de Neoplasia , Antígenos CD19 , Tratamiento Basado en Trasplante de Células y Tejidos
9.
Infect Drug Resist ; 15: 7509-7517, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36570711

RESUMEN

Background: Metagenomic next-generation sequencing (mNGS) is a fast, sensitive and accurate diagnostic method for pathogens detection. However, reports on the application of mNGS in mucormycosis remain scarce. Methods: From January 2019 to December 2021, we recruited 13 patients with hematological malignancies who were suspected of mucormycosis and completed mNGS in D20. Then we retrospectively analyze the clinical data, diagnosis, therapeutic process, and outcomes. In order to evaluate the diagnostic value of mNGS in hematological malignancies patients with suspected mucormycosis. Results: All patients had high risk factors of Invasive Fungal Disease, including hematopoietic stem cell transplantation, immunosuppression, glucocorticoids, etc. The clinical presentations were pulmonary (n=9), rhino-orbito-cerebral (n=4). But the manifestations were nonspecific. All enrolled patients completed mNGS. And most (8/13, 61.54%) of the samples were from blood. Fungi can be detected in all specimens, including Rhizopus (n=7), Rhizomucor (n=4) and Mucor (n=2). In addition, 7/13 (53.85%) specimens were detected bacteria at the same time and virus were detected in 5/13 (38.46%). Histopathological examination was completed in 5 patients, 3 of which were completely consistent with the results of mNGS. After treatment, 6 patients were cured, while the other 7 patients died. Conclusion: mNGS may be a complementary method for early diagnosis, especially for patients who are not suitable for histopathology examination or unable to obtain culture specimen. mNGS can also help detect bacteria and viruses simultaneously, allowing for appropriate and timely antibiotic administration and thus improving patient outcomes.

10.
Chem Commun (Camb) ; 58(60): 8392-8395, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35792563

RESUMEN

A unique approach to vertex-selective catalytic B-H amination at either the B(3)- or B(4)-position in o-carboranes has been developed. Using different transition metal catalysts, dehydrogenative BH/NH cross-coupling of o-carboranes and free amines has been achieved, leading to a wide variety of cage B(3)- or B(4)-aminated o-carboranes in moderate to high yields with excellent regioselectivity, where carboranyl carboxylic acids and amines can serve as competent coupling partners without any pre-functionalization. The isolation and structural identification of a key intermediate provide an insight into the reaction mechanism in the catalytic B(4)-H amination.

11.
J Hematol Oncol ; 15(1): 88, 2022 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-35799191

RESUMEN

Relapsed or refractory (R/R) acute myeloid leukemia (AML) has a poor prognosis. In this study, we evaluated chimeric antigen receptor (CAR) T cell therapy targeting CLL-1 in adults with R/R AML patients. Patients received conditioning chemotherapy with cyclophosphamide (500 mg/m2) and fludarabine (30 mg/m2) for 3 days and an infusion of a dose of 1-2 × 106 CAR-T cells/kg. The incidence of dose-limiting toxicity was the primary endpoint. Ten patients were treated, and all developed cytokine release syndrome (CRS); 4 cases were low-grade, while the remaining 6 were considered high-grade CRS. No patient developed CAR-T cell-related encephalopathy syndrome (CRES). Severe pancytopenia occurred in all patients. Two patients died of severe infection due to chronic agranulocytosis. The complete response (CR)/CR with incomplete hematologic recovery (CRi) rate was 70% (n = 7/10). The median follow-up time was 173 days (15-488), and 6 patients were alive at the end of the last follow-up. CAR-T cells showed peak expansion within 2 weeks. Notably, CLL-1 is also highly expressed in normal granulocytes, so bridging hematopoietic stem cell transplantation (HSCT) may be a viable strategy to rescue long-term agranulocytosis due to off-target toxicity. In conclusion, this study is the first to demonstrate the positive efficacy and tolerable safety of CLL-1 CAR-T cell therapy in adult R/R AML.


Asunto(s)
Agranulocitosis , Leucemia Linfocítica Crónica de Células B , Leucemia Mieloide Aguda , Adulto , Antígenos CD19 , Síndrome de Liberación de Citoquinas , Humanos , Inmunoterapia Adoptiva/efectos adversos , Leucemia Mieloide Aguda/terapia , Linfocitos T
13.
Chem Commun (Camb) ; 57(64): 7930-7933, 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34286747

RESUMEN

A strategy for one-pot synthesis of isoindoles is described via a catalytic multicomponent dehydrogenative annulation of diarylimines, vinyl ketones and simple amines. In the presence of a rhodium catalyst and Cu oxidant, four C-H and two N-H bonds are activated along with the formation of one new C-C and two new C-N bonds, leading to a series of isoindole derivatives in good to very high isolated yields.

14.
Cancer Sci ; 112(9): 3636-3644, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34185931

RESUMEN

Acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) are usually associated with poor outcomes, especially in high-risk AML/MDS. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only curative option for patients suffering from high-risk AML/MDS. However, many patients relapse after allo-HSCT. Novel therapy to prevent relapse is urgently needed. Both the BCL-2 inhibitor venetoclax (VEN) and the hypomethylating agent decitabine (DEC) possess significant antitumor activity effects against AML/MDS. Administration of DEC has been shown to ameliorate graft-versus-host disease (GVHD) and boost the graft-versus-leukemia (GVL) effect post-transplantation. We therefore conducted a prospective study (ChiCTR1900025374) to examine the tolerability and efficacy of a maintenance therapy of low-dose decitabine (LDEC) plus VEN to prevent relapse after allo-HSCT for high-risk AML/MDS patients. Twenty patients with high-risk AML (n = 17) or high-risk MDS (n = 3) post-transplantation were recruited. Approximately day 100 post-transplantation, all patients received LDEC (15 mg/m2 for 3 d) followed by VEN (200 mg) on d 1-21. The cycle interval was 2 mo, and there was 10 cycles. The primary end points of this study were rates of overall survival (OS) and event-free survival (EFS). The secondary endpoints included adverse events (AEs), cumulative incidence of relapse (CIR), nonrelapse mortality (NRM), incidences of acute GVHD (aGVHD) and chronic GVHD (cGVHD), and incidences of viral infection after allo-HSCT. Survival outcomes were assessed using Kaplan-Meier analysis. The median follow-up was 598 (149-1072) d. Two patients relapsed, 1 died, and 1 is still alive after the second transplant. The 2-y OS and EFS rates were 85.2% and 84.7%, respectively. The median 2-y EFS time was 525 (149-1072) d, and 17 patients still had EFS and were alive at the time of this writing. The most common AEs were neutropenia, anemia, thrombocytopenia, neutropenic fever, and fatigue. Grade 2 or 3 AEs were observed in 35% (7/20) and 20% (4/20) of the patients, respectively. No grade >3 AEs were observed. aGVHD (any grade) and cGVHD (limited or extensive) occurred in 55% and 20% of patients, respectively. We conclude that LDEC + VEN can be administered safely after allo-HSCT with no evidence of an increased incidence of GVHD, and this combination decreases the relapse rate in high-risk AML/MDS patients. This novel maintenance therapy may be a promising way to prevent relapse in high-risk AML/MDS patients.


Asunto(s)
Antimetabolitos Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Compuestos Bicíclicos Heterocíclicos con Puentes/efectos adversos , Decitabina/efectos adversos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/cirugía , Síndromes Mielodisplásicos/tratamiento farmacológico , Síndromes Mielodisplásicos/cirugía , Sulfonamidas/efectos adversos , Acondicionamiento Pretrasplante/métodos , Adulto , Anciano , Antimetabolitos Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Compuestos Bicíclicos Heterocíclicos con Puentes/administración & dosificación , Decitabina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Supervivencia sin Progresión , Estudios Prospectivos , Recurrencia , Sulfonamidas/administración & dosificación , Trasplante Homólogo/efectos adversos , Adulto Joven
15.
Org Lett ; 23(11): 4163-4167, 2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-33983035

RESUMEN

We disclose herein the first example of iron-catalyzed regioselective intramolecular C-H/B-H dehydrogenative coupling, affording unprecedented C,B-substituted carborane-fused phenanthroline derivatives. The 8-aminoquinoline type auxiliaries not only serve as the bidentate directing groups but also ingeniously become the core part of the final products. The mechanistic hypothesis includes B-H activation, directing group rotation promoted by trans effect, C-H activation, and reductive elimination.

16.
Cancer Immunol Immunother ; 70(12): 3501-3511, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33899130

RESUMEN

The persistence or recurrence of minimal residual disease (MRD) after chemotherapy predicts relapse of B-cell acute lymphoblastic leukemia (B-ALL). CD19-directed chimeric antigen receptor T (CD19 CAR-T) cells have shown promising responses in B-ALL. However, their role in chemotherapy-refractory MRD-positive B-ALL remains unclear. Here we aimed to assess the effectiveness and safety of CD19 CAR-T cells in MRD-positive B-ALL patients. From January 2018, a total of 14 MRD-positive B-ALL patients received one or more infusions of autogenous CD19 CAR-T cells. Among them, 12 patients achieved MRD-negative remission after one cycle of CAR-T infusion. At a median follow-up time of 647 days (range 172-945 days), the 2-year event-free survival rate in MRD-positive patients was 61.2% ± 14.0% and the 2-year overall survival was 78.6 ± 11.0%, which were significantly higher than patients with active disease (blasts ≥ 5% or with extramedullary disease). Moreover, patients with MRD had a lower grade of cytokine release syndrome (CRS) than patients with active disease. However, the peak expansion of CAR-T cells in MRD positive patients showed no statistical difference compared to patients with active disease. Five patients received two or more CAR-T cell infusions and these patients showed a decreased peak expansion of CAR-T cell in subsequent infusions. In conclusion, pre-emptive CD19 CAR-T cell treatment is an effective and safe approach and may confer sustained remission in B-ALL patients with chemotherapy-refractory MRD. The trials were registered at www.chictr.org.cn as ChiCTR-ONN-16009862 (November 14, 2016) and ChiCTR1800015164 (March 11, 2018).


Asunto(s)
Antígenos CD19/inmunología , Linfoma de Células B/inmunología , Neoplasia Residual/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Receptores Quiméricos de Antígenos/inmunología , Linfocitos T/inmunología , Adolescente , Adulto , Anciano , Femenino , Humanos , Inmunoterapia Adoptiva/métodos , Masculino , Persona de Mediana Edad , Supervivencia sin Progresión , Recurrencia , Adulto Joven
17.
Science ; 372(6538): 175-182, 2021 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-33833121

RESUMEN

Mild methods to cleave the carbon-oxygen (C-O) bond in alkyl ethers could simplify chemical syntheses through the elaboration of these robust, readily available precursors. Here we report that dibromoboranes react with alkyl ethers in the presence of a nickel catalyst and zinc reductant to insert boron into the C-O bond. Subsequent reactivity can effect oxygen-to-nitrogen substitution or one-carbon homologation of cyclic ethers and more broadly streamline preparation of bioactive compounds. Mechanistic studies reveal a cleavage-then-rebound pathway via zinc/nickel tandem catalysis.

18.
World J Clin Cases ; 9(6): 1359-1366, 2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33644203

RESUMEN

BACKGROUND: Central nervous system graft-vs-host disease (CNS-GVHD) is a rare cause of CNS disorders after allogeneic hematopoietic stem cell transplantation. Currently, establishing a diagnosis of CNS-GVHD is challenging because the diagnostic criteria and diagnostic methods are not well defined and many confounding factors need to be ruled out. CASE SUMMARY: Here, we present two patients with CNS-GVHD. Both patients with a history of acute GVHD or chronic GVHD developed neurological symptoms that could not be explained by other causes, and had abnormal cerebrospinal fluid (CSF) studies as determined by CSF and blood immune biomarker examinations, suggestive of suspected CNS-GVHD. Due to the lack of specific magnetic resonance imaging abnormalities and the rapid clinical deterioration of the patients, we did not attempt to perform a brain biopsy, but prompted the initiation of empirical immunosuppressive therapy. In view of the rapid and favorable response to local and systematic immunosuppressive treatment and the aforementioned neurologic manifestations together with CSF abnormalities and other negative findings, a final diagnosis of CNS-GVHD was made. CONCLUSION: CSF and blood immune biomarker examinations facilitated the diagnosis of CNS-GVHD, which are particularly suitable for patients who are critically ill and require urgent treatment and for those who are unsuitable for invasive diagnostic procedures.

19.
BMC Infect Dis ; 21(1): 192, 2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33602128

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) has caused a global pandemic that has raised worldwide concern. This study aims to investigate the correlation between the extent of lung infection and relevant clinical laboratory testing indicators in COVID-19 and to analyse its underlying mechanism. METHODS: Chest high-resolution computer tomography (CT) images and laboratory examination data of 31 patients with COVID-19 were extracted, and the lesion areas in CT images were quantitatively segmented and calculated using a deep learning (DL) system. A cross-sectional study method was carried out to explore the differences among the proportions of lung lobe infection and to correlate the percentage of infection (POI) of the whole lung in all patients with clinical laboratory examination values. RESULTS: No significant difference in the proportion of infection was noted among various lung lobes (P > 0.05). The POI of total lung was negatively correlated with the peripheral blood lymphocyte percentage (L%) (r = - 0.633, P < 0.001) and lymphocyte (LY) count (r = - 0.555, P = 0.001) but positively correlated with the neutrophil percentage (N%) (r = 0.565, P = 0.001). Otherwise, the POI was not significantly correlated with the peripheral blood white blood cell (WBC) count, monocyte percentage (M%) or haemoglobin (HGB) content. In some patients, as the infection progressed, the L% and LY count decreased progressively accompanied by a continuous increase in the N%. CONCLUSIONS: Lung lesions in COVID-19 patients are significantly correlated with the peripheral blood lymphocyte and neutrophil levels, both of which could serve as prognostic indicators that provide warning implications, and contribute to clinical interventions in patients.


Asunto(s)
COVID-19/diagnóstico por imagen , Pulmón/patología , Aprendizaje Automático , Adulto , Prueba de COVID-19 , Técnicas de Laboratorio Clínico , Estudios Transversales , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/virología , Recuento de Linfocitos , Linfocitos/citología , Masculino , Persona de Mediana Edad , Neutrófilos/citología , Pandemias , Pronóstico , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X
20.
J Am Chem Soc ; 142(15): 6940-6945, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32233359

RESUMEN

Copper-catalyzed electrochemical selective cage B-H oxygenation of o-carboranes has been achieved for the first time. Under a constant electric current (4.0 mA) at room temperature, copper-catalyzed cross-coupling of carboranyl amides with lithium phenolates results in the formation of B(4,5)-diphenolated o-carboranes via direct B-H activation, whereas the use of lithium tert-butoxide affords B(4)-monooxygenated products. This reaction does not require any additional chemical oxidants and generates H2 and a lithium salt as byproducts. Control experiments indicated that a high-valent Cu(III) species is likely involved in the reaction process.

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