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This publication aims at presenting a Python-based workflow designed to enable a fully automatised and exhaustive exploration of the conformational degrees of freedom within the calculation of reaction paths in molecular systems. The proposed strategy focuses on effectively representing the lowest energy conformers for intricate, highly rotatable, and non-intuitive transition states, reagents and products, using existing computational tools. The article presents a workflow that is demonstrated through the application of five chemical reactions, chosen to be representative of the diversity and complexity of actual experimental studies, and which often prove to be challenging to study "by hand". The proposed methodology is expected to be of a great help in the modelling of state-of-the art organic chemistry reactions, whose complexity is ever increasing.

Context: In this article, we adapt a recent proposition to use a Fermi-Dirac-type population scheme on Kohn-Sham molecular orbitals to the case of an interaction with a thermalised electrode. This allows to derive a fundamental non-linear equation linking the chemical potential of the electrode and the amount of charge transferred to the system under study, hence allows to quantify the propensity to charge transfer (philicity). This methodology is applied to a large set of common electrophiles and nucleophiles, showing decent relation with more standard philicity descriptors. Chemical hardness is also revisited by this approach., Methods: All calculations were performed using the Gaussian 16 software package at the M062X/aug-cc-pvtz level of theory. Data analysis was then performed through a Python3 dedicated program (relying on the fsolve numerical solver from the SciPy package), using Gaussian output files, and available as supplementary material., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Furfural is an industrially relevant biobased chemical platform. Unlike classical furan, or C-alkylated furans, which have been previously described in the current literature, the =C 5 H bond of furfural is unreactive. As a result, on a large scale, C=C and C=O bond hydrogenation/hydrogenolysis is mainly performed, with furfuryl alcohol and methyl tetrahydrofuran being the two main downstream chemicals. Here, we show that the derivatization of the -CHO group of furfural restores the reactivity of its =C 5 H bond, thus permitting its double condensation on various alkyl aldehydes. Overcoming the recalcitrance of the =C 5 H bond of furfural has opened an access to a biobased monomer, whose potential have been investigated in the fabrication of renewably-sourced poly(silylether). By means of a combined theoretical-experimental study, a reactivity scale for furfural and its protected derivatives against carbonylated compounds has been established using an electrophilicity descriptor, a means to predict the molecular diversity and complexity this pathway may support, and also to de-risk any project related to this topic. Finally, by using performance criteria for industrial operations in the field of fuels and commodities, we discussed the industrial potential of this work in terms of cost, E-factor, reactor productivity and catalyst consumption., (© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

The Hock cleavage, which is compatible with tandem processes, was applied to the synthesis of 1-aryltetralines through a one-pot transformation from readily available benzyl(prenyl)malonate substrates. After the photooxygenation of the prenyl moiety, the resulting hydroperoxide was directly engaged in a Hock cleavage by adding a Lewis acid. The presence of an aromatic nucleophile in the reaction mixture and that of a benzyl moiety on the substrate resulted in tandem Friedel-Crafts reactions to form the 1-aryltetraline products. These compounds share a close analogy to the cyclolignan natural products. Experimental observations and a DFT study support the involvement of an aldehyde intermediate during the Friedel-Crafts reactions, rather than an oxocarbenium., (Copyright © 2024, Ikonnikova et al.)

The acid-catalyzed rearrangement of organic peroxides is generally associated with C-C-bond cleavages (Hock and Criegee rearrangements), with the concomitant formation of an oxocarbenium intermediate. This article describes the tandem process between a Hock or Criegee oxidative cleavage and a nucleophilic addition onto the oxocarbenium species (in particular a Hosomi-Sakurai-type allylation), under InCl 3 catalysis. It was applied to the synthesis of 2-substituted benzoxacycles (chromanes and benzoxepanes), including a synthesis of the 2-(aminomethyl)chromane part of sarizotan, and a total synthesis of erythrococcamide B.

The lactonization of 2-(2-nitrophenyl)-1,3-cyclohexanediones containing an alcohol side chain and up to three distant prochiral elements is reported by isomerization under the mediation of simple organocatalysts such as quinidine. Through a process of ring expansion, strained nonalactones and decalactone are produced with up to three stereocenters in high er and dr (up to 99 : 1). Distant groups, including alkyl, aryl, carboxylate and carboxamide moieties, were examined., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Aspochalasins are leucine-derived cytochalasins. Their complexity is associated with a high degree of biosynthetic oxidation, herein inspiring a two-phase strategy in total synthesis. We thus describe the synthesis of a putative biomimetic tetracyclic intermediate. The constructive steps are an intramolecular Diels-Alder reaction to install the isoindolone core of cytochalasins, whose branched precursor was obtained from a stereoselective Ireland-Claisen rearrangement performed from a highly unsaturated substrate. This also constitutes a formal synthesis of trichoderone A.

A highly enantioselective synthesis of α-branched acrylonitriles is reported featuring a one-pot sequential asymmetric Michael addition/retro-Dieckmann/retro-Michael fragmentation cascade. The method, which relies on a solid, bench-stable, and commercially available acrylonitrile surrogate, is practical, scalable, and highly versatile and provides a direct access to a wide range of enantioenriched nitrile-containing building blocks. Most importantly, the method offers a new tool to incorporate an acrylonitrile moiety in an asymmetric fashion.

An intramolecular Diels-Alder (IMDA) reaction efficiently accelerated by Schreiner's thiourea is reported, to build a functionalized cytochalasin scaffold (periconiasin series) for biological purposes. DFT calculation highlighted a unique multidentate cooperative hydrogen bonding in this catalysis. The deprotection end game afforded a collection of diverse structures and showed the peculiar reactivity of the Diels-Alder cycloadducts upon functionalization. Biological studies revealed strong cytotoxicity of a few compounds on breast cancer cell lines while actin polymerization is preserved., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: The South African Triage Scale (SATS) has demonstrated good validity in the EDs of Médecins Sans Frontières (MSF)-supported sites in Afghanistan and Haiti; however, corresponding reliability in these settings has not yet been reported on. This study set out to assess the inter-rater and intrarater reliability of the SATS in four MSF-supported EDs in Afghanistan and Haiti (two trauma-only EDs and two mixed (including both medical and trauma cases) EDs)., Methods: Under classroom conditions between December 2013 and February 2014, ED nurses at each site assigned triage ratings to a set of context-specific vignettes (written case reports of ED patients). Inter-rater reliability was assessed by comparing triage ratings among nurses; intrarater reliability was assessed by asking the nurses to retriage 10 random vignettes from the original set and comparing these duplicate ratings. Inter-rater reliability was calculated using the unweighted kappa, linearly weighted kappa and quadratically weighted kappa (QWK) statistics, and the intraclass correlation coefficient (ICC). Intrarater reliability was calculated according to the percentage of exact agreement and the percentage of agreement allowing for one level of discrepancy in triage ratings. The correlation between years of nursing experience and reliability of the SATS was assessed based on comparison of ICCs and the respective 95% CIs., Results: A total of 67 nurses agreed to participate in the study: In Afghanistan there were 19 nurses from Kunduz Trauma Centre and nine from Ahmed Shah Baba; in Haiti, there were 20 nurses from Martissant Emergency Centre and 19 from Tabarre Surgical and Trauma Centre. Inter-rater agreement was moderate across all sites (ICC range: 0.50-0.60; QWK range: 0.50-0.59) apart from the trauma ED in Haiti where it was moderate to substantial (ICC: 0.58; QWK: 0.61). Intrarater agreement was similar across the four sites (68%-74% exact agreement); when allowing for a one-level discrepancy in triage ratings, intrarater reliability was near perfect across all sites (96%-99%). No significant correlation was found between years of nursing experience and reliability., Conclusion: The SATS has moderate reliability in different EDs in Afghanistan and Haiti. These findings, together with concurrent findings showing that the SATS has good validity in the same settings, provide evidence to suggest that SATS is suitable in trauma-only and mixed EDs in low-resource settings., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Objective: To assess the validity of the South African Triage Scale (SATS) in four Médecins Sans Frontières (MSF)-supported emergency departments (ED, two trauma-only sites, one mixed site (both medical and trauma cases) and one paediatric-only site) in Afghanistan, Haiti and Sierra Leone., Methods: This was a retrospective cohort study conducted between June 2013 and June 2014. Validity was assessed by comparing patients' SATS ratings with their final ED outcome (ie, hospital admission, death or discharge)., Results: In the two trauma settings, the SATS demonstrated good validity: it accurately predicted an increase in the likelihood of mortality and hospitalisation across incremental acuity levels (p<0.001) and ED outcomes for 'green' and 'red' patients matched the predicted ED outcomes in 84%-99% of cases. In the mixed ED, the SATS was able to predict an incremental increase in hospitalisation (p<0.001) across both trauma and non-trauma cases. In the paediatric-only settings, SATS was able to predict an incremental increase in hospitalisation in the non-trauma cases only (p<0.001). However, 87% (non-trauma) and 94% (trauma) of 'red' patients in the mixed-medical setting were overtriaged and 76% (non-trauma) and 100% (trauma) of 'green' patients in the paediatric settings were undertriaged., Conclusion: The SATS is a valid tool for trauma-only settings in low-resource countries. Its use in mixed settings seems justified, but context-specific assessments would seem prudent. Finally, in paediatric settings with endemic malaria, adding haemoglobin level to the SATS discriminator list may help to improve the undertriage of patients with malaria., Competing Interests: Competing interests: No, there are no competing interests.

Background: Trauma is a leading cause of death and represents a major problem in developing countries where access to good quality emergency care is limited. Médecins Sans Frontières delivered a standard package of care in two trauma emergency departments (EDs) in different violence settings: Kunduz, Afghanistan, and Tabarre, Haiti. This study aims to assess whether this standard package resulted in similar performance in these very different contexts., Methods: A cross-sectional study using routine programme data, comparing patient characteristics and outcomes in two EDs over the course of 2014., Results: 31 158 patients presented to the EDs: 22 076 in Kunduz and 9082 in Tabarre. Patient characteristics, such as delay in presentation (29.6% over 24 h in Kunduz, compared to 8.4% in Tabarre), triage score, and morbidity pattern differed significantly between settings. Nevertheless, both EDs showed an excellent performance, demonstrating low proportions of mortality (0.1% for both settings) and left without being seen (1.3% for both settings), and acceptable triage performance. Physicians' maximum working capacity was exceeded in both centres, and mainly during rush hours., Conclusions: This study supports for the first time the plausibility of using the same ED package in different settings. Mapping of patient attendance is essential for planning of human resources needs., (© The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)

We have previously developed a Patient Data Management System for Intensive Care based on Open Source Software. The aim of this work was to adapt this software to use in Emergency Departments in low resource environments. The new software includes facilities for utilization of the South African Triage Scale and prediction of mortality based on independent predictive factors derived from data from the Tabarre Emergency Trauma Center in Port au Prince, Haiti.