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This paper focuses on system concept use in teaching either chemical core concepts or interdisciplinary chemistry-related topics. The system concept is important in order to develop global competences, and chemistry teaching plays a key role in this context. A questionnaire has been administered to two different samples, Italian teachers and International Baccalaureate (IB) teachers, in order to investigate their opinions about the issues involved. The most significant differences and similarities emerging from the survey have been analyzed mostly by dendrograms and then commented on. With due caution, it is possible to suppose similar attitudes in the two groups of teachers except for some aspects. For example, the analysis of system concept knowledge within pure chemistry highlights some deficiencies: Italian teachers in particular show a low level of epistemological awareness about the systemic character of chemistry, whereas its knowledge would allow not only a chemistry teaching improvement but also a productive use of chemical explanations in other scientific and nonscientific fields, especially in the social sciences; as a consequence, it would facilitate interdisciplinary teaching. Therefore, science teachers need epistemological insight into chemical systemic aspects, that may be provided by high quality textbooks and training initiatives focusing on the systemic character of chemistry and its interdisciplinary connections. In an analysis of chemistry teachers only, Italian teachers support interdisciplinary teaching more strongly than IB teachers, despite the rigidity and the state of crisis of the Italian education system, often attributed to a lack of broad-minded teachers. This evidence indicates a promising resource for the Italian education system. Moreover, a similar kind of questionnaire can be utilized by other education researchers in order to isolate and analyze some teachers' attitudes regardless the very different education systems in which every sample works.

Tris(pyrazolyl)methane (tpm), 2,2,2-tris(pyrazolyl)ethanol (tpmOH) and its esterification derivatives with ibuprofen and flurbiprofen (tpmIBU and tpmFLU) were used as ligands to obtain complexes of the type [Fe(tpmX)2]Cl2 (1–4). The tpmIBU and tpmFLU ligands and corresponding complexes 3 and 4 were characterized by IR and multinuclear NMR spectroscopy, and the structure of tpmIBU was elucidated by single crystal X-ray diffraction. Complexes 1–4 were also assessed for their behaviour in aqueous media (solubility in D2O, octanol/water partition coefficient, stability in physiological-like conditions). The antiproliferative activity of ligands and complexes was determined on A2780, A2780cis and A549 cancer cell lines and the non-cancerous HEK 293T and BJ cell lines. The ligands and complexes were investigated for their ability to inhibit COX-2 (cyclooxygenase) and HNE (4-hydroxynonenal) enzymes. Complexes 3 and 4 exhibited cytotoxicity that may be attributed predominantly to their bioactive fragments, while DNA binding and enhancement of ROS production do not appear to play any significant role. [ABSTRACT FROM AUTHOR]

In the synthesis of metal–organic frameworks (MOFs), the choice of the metal precursor plays a key role because of the influence that it can exert on the crystallization kinetics. The present work explores the use of metal-carbamato complexes for the synthesis of benchmark MOFs, namely HKUST-1 and UiO-66. Cu2(O2CNEt2)4·2NHEt2 and Zr(O2CNEt2)4, prepared using straightforward CO2 fixation reactions starting from the corresponding metal chlorides and diethylamine, were employed as metal precursors for MOF formation. The synthesis conditions, including the solvent, temperature, and ligand protonation degree, were systematically investigated, revealing metal carbamates as highly reactive precursors due to their prompt release of CO2 and amine upon reaction with protic species, i.e., the polycarboxylic linkers. This property of metal carbamates allowed us to identify room temperature protocols to achieve MOFs with comparable properties to those obtained using traditional metal precursors. Subsequent optimization of the reaction conditions led to the design of a one-pot synthetic strategy for HKUST-1, starting directly from copper(II) chloride and diethylamine under a CO2 atmosphere. The MOFs were characterized using various techniques, including powder X-ray diffraction, N2 sorption analysis, 1H nuclear magnetic resonance spectroscopy, and CHN elemental analysis, and compared to reference samples prepared according to literature procedures. [ABSTRACT FROM AUTHOR]