6 research outputs found
Temperature-Controlled Mechanochemistry for the Nickel-Catalyzed Suzuki-Miyaura-Type Coupling of Aryl Sulfamates via Ball Milling and Twin-Screw Extrusion
The use of temperature-controlled mechanochemistry to enable the mechanochemical nickel-catalyzed Suzuki-Miyaura coupling is herein described. Transitioning from a capricious room-temperature protocol, through to a heated, PID-controlled programmable jar heater manifold was required to deliver an efficient method for the coupling of aryl sulfamates (derived from ubiquitous phenols) and aryl boronic acid species. Furthermore, this process is conducted using a base-metal nickel catalyst, in the absence of bulk solvent, and in the absence of air/moisture sensitive reaction set-ups. This methodology is showcased through translation to large-scale twin-screw extrusion methodology enabling 200-fold scale increase, producing decagram quantities of C-C coupled material
Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial
SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87â1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98â1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87â1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication
Temperature-Controlled Mechanochemistry for the Nickel-Catalyzed Suzuki-Miyaura-Type Coupling of Aryl Sulfamates via Ball Milling and Twin-Screw Extrusion
The use of temperature-controlled mechanochemistry to enable the mechanochemical nickel-catalyzed Suzuki-Miyaura coupling is herein described. Transitioning from a capricious room-temperature protocol, through to a heated, PID-controlled programmable jar heater manifold was required to deliver an efficient method for the coupling of aryl sulfamates (derived from ubiquitous phenols) and aryl boronic acid species. Furthermore, this process is conducted using a base-metal nickel catalyst, in the absence of bulk solvent, and in the absence of air/moisture sensitive reaction set-ups. This methodology is showcased through translation to large-scale twin-screw extrusion methodology enabling 200-fold scale increase, producing decagram quantities of C-C coupled material
Mechanochemical techniques for the activation and use of zero-valent metals in synthesis
Activating raw, zero-valent metals is an essential capability for chemical processes, which include synthesis and catalysis. In recent years there has been the discovery and growing intensity in the use of mechanical action, through the utility of ball mills, to facilitate the activation of zero-valent metals. The complexity of the synthetic reaction systems in which these processing techniques can be used has now reached a tipping-point, with, among others, cross-electrophile coupling, radical reactions and new modes of zero-valent reactivity demonstrated. In addition, the technique of ball milling is synonymous with solvent minimization for the reaction component of a synthetic process. In this review, we demonstrate that, together, these developments paint an intriguing picture in which the combination of the technique of ball milling and chemical synthesis mediated by zero-valent metals could deliver a sustainable platform for chemical synthesis, catalysis and new reaction discovery for the future
On the Valorisation of Chitin-Derived Furans by Ball Milling.
Aromatic compounds containing nitrogen atoms in their structure are currently obtained from non-renewable sources with the incorporation of nitrogen from ammonia, which is industrially produced by the highly energy demanding Haber process. To minimize the carbon footprint of nitrogen containing chemicals and drive the production of nitrogenated aromatic compounds in a Haber-independent manner, the use of furans derived from chitin has become an affordable and promising source for nitrogen fixation in compounds with high added-value. Herein, we address the challenge of using two chitin-derived furans, 3-acetamido-5-acetylfuran (3A5AF) and 3-acetamido-5-furfural aldehyde (3A5F), to favor the formation of exo DielsâAlder adducts and 4-acetylaminophthalimides using Mechanochemistry, as a more sustainable and cleaner synthesis compared to the classical methods in solution-phase. The Mechanochemistry activation is explored through the synthesis of novel 7-oxa-norbornene backbones and it showed an improvement in both yield and exo:endo selectivity when compared to solution-phase, with yields reaching up to 77% and selectivity >19:1. We also investigated the use of a less toxic and commercially available hydrazine in order to promote the synthesis of 4-acetylaminophthalimides from 3A5F in yields ranging 20â79%
Pregnancy and neonatal outcomes of COVID -19: coreporting of common outcomes from PAN-COVID and AAP-SONPM registries
Objective
Few large cohort studies have reported data on maternal, fetal, perinatal and neonatal outcomes associated with severe acute respiratory syndrome coronavirus 2 (SARSâCoVâ2) infection in pregnancy. We report the outcome of infected pregnancies from a collaboration formed early during the pandemic between the investigators of two registries, the UK and Global Pregnancy and Neonatal outcomes in COVIDâ19 (PANâCOVID) study and the American Academy of Pediatrics (AAP) Section on NeonatalâPerinatal Medicine (SONPM) National Perinatal COVIDâ19 Registry.
Methods
This was an analysis of data from the PANâCOVID registry (1 January to 25 July 2020), which includes pregnancies with suspected or confirmed maternal SARSâCoVâ2 infection at any stage in pregnancy, and the AAPâSONPM National Perinatal COVIDâ19 registry (4 April to 8 August 2020), which includes pregnancies with positive maternal testing for SARSâCoVâ2 from 14âdays before delivery to 3âdays after delivery. The registries collected data on maternal, fetal, perinatal and neonatal outcomes. The PANâCOVID results are presented overall for pregnancies with suspected or confirmed SARSâCoVâ2 infection and separately in those with confirmed infection.
Results
We report on 4005 pregnant women with suspected or confirmed SARSâCoVâ2 infection (1606 from PANâCOVID and 2399 from AAPâSONPM). For obstetric outcomes, in PANâCOVID overall and in those with confirmed infection in PANâCOVID and AAPâSONPM, respectively, maternal death occurred in 0.5%, 0.5% and 0.2% of cases, early neonatal death in 0.2%, 0.3% and 0.3% of cases and stillbirth in 0.5%, 0.6% and 0.4% of cases. Delivery was preterm (<â37âweeks' gestation) in 12.0% of all women in PANâCOVID, in 16.1% of those women with confirmed infection in PANâCOVID and in 15.7% of women in AAPâSONPM. Extreme preterm delivery (<â27âweeks' gestation) occurred in 0.5% of cases in PANâCOVID and 0.3% in AAPâSONPM. Neonatal SARSâCoVâ2 infection was reported in 0.9% of all deliveries in PANâCOVID overall, in 2.0% in those with confirmed infection in PANâCOVID and in 1.8% in AAPâSONPM; the proportions of neonates tested were 9.5%, 20.7% and 87.2%, respectively. The rates of a smallâforâgestationalâage (SGA) neonate were 8.2% in PANâCOVID overall, 9.7% in those with confirmed infection and 9.6% in AAPâSONPM. Mean gestationalâageâadjusted birthâweight Zâscores were â0.03 in PANâCOVID and â0.18 in AAPâSONPM.
Conclusions
The findings from the UK and USA registries of pregnancies with SARSâCoVâ2 infection were remarkably concordant. Preterm delivery affected a higher proportion of women than expected based on historical and contemporaneous national data. The proportions of pregnancies affected by stillbirth, a SGA infant or early neonatal death were comparable to those in historical and contemporaneous UK and USA data. Although maternal death was uncommon, the rate was higher than expected based on UK and USA population data, which is likely explained by underascertainment of women affected by milder or asymptomatic infection in pregnancy in the PANâCOVID study, although not in the AAPâSONPM study. The data presented support strong guidance for enhanced precautions to prevent SARSâCoVâ2 infection in pregnancy, particularly in the context of increased risks of preterm delivery and maternal mortality, and for priority vaccination of pregnant women and women planning pregnancy. Copyright © 2021 ISUOG. Published by John Wiley & Sons Ltd