Sulfur and nitrogen half-mustard compounds lose their aggressive properties when the chlorine atom is replaced by a carbonate moiety. The anchimeric effect of the novel mustard carbonate analogues is investigated. The reaction follows first-order kinetics, does not need any base, and occurs

Aedes aegypti, the main arbovirus vector of the Yellow fever, Dengue, Chikungunya and Zika viruses, is widely distributed in tropical and subtropical areas throughout the world. Preventive control efforts have been implemented worldwide aimed at reducing its impact on human health. The recent reduction of chemicals available for vector control due to their negative impact on the environment and human health and the increase in mosquito resistance to insecticides have driven the research community to identify and evaluate sustainable alternatives to synthetic insecticides. In this study, the potential larvicidal effect of essential oils extracted from Ocimum campechianum, Ocotea quixos and Piper aduncum were tested in vitro. GC and GC–MS analyses showed that the main compounds were eugenol (18%), 1,8-cineole (39%) and dillapiole (48%), respectively. Susceptibility to essential oils was measured according to the WHO protocol. After 24 h, the mean percentage mortality ranged from 2.7 to 100% for P. aduncum, from 2.2 to 100% for O. campechianum, and from 2.9 to 100% for O. quixos. The highest potential was displayed by P. aduncum, followed by O. campechianum and O. quixos, with LC50 values of 25.7, 69.3 and 75.5 ppm, respectively. The rapid and effective larvicidal activity of these three oils led us to consider these results to be promising, also considering the possibility of local cultivation of these plants in tropical and subtropical areas and the simple technology for their large-scale preparation and production. Further studies are needed to evaluate the individual components and their activity as larvicides.

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New ambient temperature liquid calcium alkoxides, [Ca(O(CH 2 CH 2 O) 3 CH 3 ) 2 ] (1) and(3), were synthesised by reaction of ammonia-activated calcium with the appropriate alcohol. Their potentiality as stone consolidant products was investigated and compared with those of other alkoxides: [Ca(OCH 2 CH 3 ) 2 (CH 3 CH 2 OH) 4 ] (4), [Ca(OCH 3 ) 2 ] (5), [{Ca(OCH 2 CH 2 OCH 3 ) 2 } 9 ] (6), already described in the literature. Reaction of 1-3 with the atmosphere was studied, final products analysed and kinetic pathways investigated. The reaction produces CaCO 3 and the vaterite/calcite ratios observed in the coatings generated from isopropyl alcohol solutions of 1-6 were found to considerably vary with the alkoxide precursor, which has a strong influence also on the morphology of the produced films. Furthermore, their efficiency as stone consolidants was tested by ultrasound measurements.

Calcium alkoxides in solution give rise to oligomers with different reactivity and solubility and, as observed in a previous investigation, small differences in the ligand structure lead to strong differences in the cluster composition. Electrospray ionisation mass spectrometry (ESI-MS) gives evidence of this behaviour, allowing the identification of these oligomers. In this paper, ESI was applied in the study of calcium alkoxides with different steric hindrances and with additional donor atoms on the ligands. A systematic analysis was conducted by varying the ESI instrumental parameters (voltages, temperatures) to identify the best conditions for the analysis of this class of compounds. Furthermore, particular attention was paid to the study of the best solvent to be employed, considering the possible occurrence of alcoholysis and decomplexation phenomena.