Anisyl and ferrocenyl adducts of methylenepyran-containing β-diketone: Synthesis, spectral, structural, and redox properties

International audienceWittig reaction between the in situ generated [2,6-diphenyl-4H-pyran-4-yl phosphorane and methyl 4-formylbenzoate afforded the methyl 4-[(2,6-diphenyl-4H-pyran-4-ylidene)methyl]benzoate precursor 2 in 75% yield. The anisyl and ferrocenyl adducts of methylenepyran-containing β-diketones 3 and 4, respectively, were prepared from the base-catalyzed Claisen condensation reaction between precursor 2 and 4-methoxyacetophenone or acetylferrocene, using t-BuO−K+ as basic initiator. Both β-diketones 3 and 4 were isolated as an orange and dark-red crystalline solids in 50% yield, respectively. The acetyl derivative 6, 1-acetyl-1′-methylenepyranyl-ferrocene, was synthesized following a classical Friedel-Crafts acylation reaction of the parent ferrocenylmethylenepyran 5, and isolated in 61% yield as a red microcrystalline powder. The condensation reaction between the electron-rich acetyl complex 6 and acetyl acetate, using lithium diisopropylamide as the active base initiator, provided the ferrocenylmethylenepyran-containing β-diketone, 1-(1,3-dioxobutyl)-1′-[(2,6-diphenyl-4H-pyran-4-ylidene)methyl] ferrocene 7, isolated in 20% yield as an orange powder. The composition and identity of the new compounds 2-4, 6 and 7 are supported by elemental analysis, FT-IR, one- and two-dimensional 1H and 13C NMR spectral data and mass spectrometry. Additionally, the molecular structures of compounds 2, 4 and 6 were ascertained by single-crystal X-ray diffraction study. FT-IR and NMR spectral data indicate that both β-diketones 3 and 4 do solely exist as their keto-enol tautomeric form in solution and in the solid state, whereas a mixture of keto-enol and β-diketone tautomers in a 73:27 spectroscopic ratio was observed for 7. In the three cases, enolization takes place exclusively away from the anisyl or ferrocenyl group with formation of a six-membered pseudo-aromatic keto-enol ring, confirmed by the crystal structure of 4. Cyclic voltammetric measurements revealed that all the compounds undergo a single one-electron oxidation, localized presumably at the methylenepyran unit. This first oxidation generates a radical cation that undergoes an intermolecular C-C bond coupling to form the corresponding dimer. Anodically shifted to the first oxidation, cyclovoltammogram of 4 exhibits one reversible two-electron oxidation while that of 6 and 7 present two successive reversible one-electron oxidations, attributed in the three cases to the ferrocenyl fragment of the dimer

Microbial monitoring of surface water in South Africa: an overview

Infrastructural problems force South African households to supplement their drinking water consumption from water resources of inadequate microbial quality. Microbial water quality monitoring is currently based on the Colilert®18 system which leads to rapidly available results. Using Escherichia coli as the indicator microorganism limits the influence of environmental sources on the reported results. The current system allows for understanding of long-term trends of microbial surface water quality and the related public health risks. However, rates of false positive for the Colilert®18-derived concentrations have been reported to range from 7.4% to 36.4%. At the same time, rates of false negative results vary from 3.5% to 12.5%; and the Colilert medium has been reported to provide for cultivation of only 56.8% of relevant strains. Identification of unknown sources of faecal contamination is not currently feasible. Based on literature review, calibration of the antibiotic-resistance spectra of Escherichia coli or the bifidobacterial tracking ratio should be investigated locally for potential implementation into the existing monitoring system. The current system could be too costly to implement in certain areas of South Africa where the modified H2S strip test might be used as a surrogate for the Colilert®18

Cabbage intercropping in literature

A database compiling published data on cabbage intercropping, in terms of productivity and product quality

Database of intercrop configurations and agroecosystems for cabbages

This database was created for the Sureveg project. It collects existing data on cabbage intercropping regarding the configuration of the system and the productivity and product quality provisioning services. It was used in a meta-analyses to study the effect of intercropping on the provisioning services of cabbage

Kinetic modeling of the hydrogenation of 1,5,9-cyclododecatriene on Pd/Al<SUB>2</SUB>O<SUB>3</SUB> Catalyst including isomerization

The kinetic modeling of the hydrogenation of 1,5,9-cyclododecatriene has been studied using a Pd/Al<SUB>2</SUB>O<SUB>3</SUB> catalyst in a slurry reactor on the basis of a complete isomers analysis. A reaction scheme involving multistep hydrogenation and reversible isomerization reactions has been considered and a kinetic model of Langmuir-Hinshelwood type proposed. The kinetic parameters were estimated from experimental batch slurry reactor data. The model predictions of cyclododecene selectivity at different pressures agree well with the experimental data

. La qualité nutritionnelle et physiologique de la graine de colza dépend de la disponibilité en eau pendant la phase reproductrice.

International audienc

Paso a paso para la inclusión de género en iniciativas de Agricultura Sostenible Adaptada al Clima para Honduras

Con el fin de hacer frente a las amenazas que el cambio climático supone para los medios de vida rurales, la República de Honduras, junto con el resto de la región Centroamericana, se ha embarcado en el diseño de medidas y políticas de adaptación y mitigación para reducir las emisiones y adaptar los sistemas de producción alimentaria para disminuir su vulnerabilidad y aumentar su resiliencia. Entre ellas, se han promovido políticas y programas de agricultura sostenible adaptada al clima, que buscan mejorar la producción y seguridad alimentaria de los sistemas productivos, al mismo tiempo que buscan mejorar la adaptación y contribuir a la mitigación de gases de efecto invernadero. En Honduras un ejemplo de estas iniciativas es la Estrategia Nacional de Adaptación al Cambio Climático del Sector Agroalimentario 2015-2025 (ENACCSA). A nivel regional ha sido la aprobación de la “Estrategia Agricultura Sostenible Adaptada al Clima (ASAC) para la Región del SICA (2018-2030)”. En este marco, las unidades de cambio climático y género de la secretaría de Agricultura y Ganadería (SAG) de Honduras junto con el programa de investigación de CGIAR en Cambio Climático, Agricultura y Seguridad Alimentaria (CCAFS) han venido trabajando conjuntamente durante los últimos años para proveer al sector agrícola nacional con herramientas con enfoque de género que permitan mejorar su capacidad de adaptación a los desafíos que la variabilidad al cambio climático están trayendo al sector. Entre 2018 y 2020 se realizaron una serie de talleres, conversatorios, reuniones y seminarios virtuales a nivel regional y nacional con el fin de fortalecer las capacidades de actores en la formulación e implementación de proyectos de vocación agrícola que integren las temáticas de género y cambio climático. En el marco de los proyectos “Generando evidencia sobre la Agricultura Sostenible Adaptada al Clima con perspectiva de género para informar políticas en Centroamérica”, “Diseñar políticas de cambio climático incluyentes para sistemas alimentarios resilientes en América Central y el Caribe”, y “Centroamérica Resiliente- ResCA”, se resaltó la necesidad de fortalecer la inclusión de igualdad de género en todas las fases de diseño e implementación de políticas y programas agrícolas, incluyendo la necesidad de crear sistemas de monitoreo más robustos que integren indicadores de género y de medidas encaminadas a mejorar la capacidad de adaptación frente a los impactos de la variabilidad y el cambio climático

Early Detection of Neurodevelopmental Disorders of Toddlers and Postnatal Depression by Mobile Health App: Observational Cross-sectional Study

BackgroundDelays in the diagnosis of neurodevelopmental disorders (NDDs) in toddlers and postnatal depression (PND) in mothers are major public health issues. In both cases, early intervention is crucial. ObjectiveWe aimed to assess if a mobile app named Malo can reduce delay in the recognition of NDD and PND. MethodsWe performed an observational, cross-sectional, data-based study in a population of young parents with a minimum of 1 child under 3 years of age at the time of inclusion and using Malo on a regular basis. We included the first 4000 users matching the criteria and agreeing to participate between November 11, 2021, and January 14, 2022. Parents received monthly questionnaires via the app, assessing skills on sociability, hearing, vision, motricity, language of their infants, and possible autism spectrum disorder. Mothers were also requested to answer regular questionnaires regarding PND, from 4-28 weeks after childbirth. When any patient-reported outcomes matched predefined criteria, an in-app notification was sent to the user, recommending the booking of an appointment with their family physician or pediatrician. The main outcomes were the median age of the infant at the time of notification for possible NDD and the median time of PND notifications after childbirth. One secondary outcome was the relevance of the NDD notification for a consultation as assessed by the physicians. ResultsAmong 4242 children assessed by 5309 questionnaires, 613 (14.5%) had at least 1 disorder requiring a consultation. The median age of notification for possible autism spectrum, vision, audition, socialization, language, or motor disorders was 11, 9, 17, 12, 22, and 4 months, respectively. The sensitivity of the alert notifications of suspected NDDs as assessed by the physicians was 100%, and the specificity was 73.5%. Among 907 mothers who completed a PND questionnaire, highly probable PND was detected in 151 (16.6%) mothers, and the median time of detection was 8-12 weeks. ConclusionsThe algorithm-based alert suggesting NDD was highly sensitive with good specificity as assessed by real-life practitioners. The app was also efficient in the early detection of PND. Our results suggest that the regular use of this multidomain familial smartphone app would permit the early detection of NDD and PND. Trial RegistrationClinicalTrials.gov NCT04958174; https://clinicaltrials.gov/ct2/show/NCT0495817