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Today, in a world context characterized by high pollution levels and increasingly limited natural resources, even in the building sector, focusing on environmental issues, through energy saving and a more rational use of these resources, both during construction and management, is fundamental. An important contribution in this direction is given by the knowledge of the durability of products and building components, especially when innovative products are applied and no information are available on the reliability and service life. The research concerns the evaluation of the durability of cement-based photocatalytic coatings ("rasanti" in the Italian diction), containing different types of pigments, used for the external finishing of the buildings envelope and applied in low thicknesses on different supports. These products were prepared using photocatalytic cements by Italcementi (TX ActiveR) The investigated aspects are: the photocatalytic properties, conferring self-cleaning attitude and reduced maintenance to the treated surfaces, and the colorimetric ones, meaning the conservation of colour and giving aesthetic quality to the building envelope. The paper presents some results carried out on TX ActiveRcement-based coatings, performed according to the ISO 15686 methodology, aimed at defining the Reference Service Life, through accelerated ageing tests in climatic chamber and the corresponding monitoring of photocatalytic and colorimetric properties. The photocatalytic tests were carried out according to the UNI 11247-2010, in terms of NOx abatement capability, and the colour measurements were taken on the CIELAB colour space.

The present work addresses the photocatalytic properties of two commercial titanias for application in concrete technology. A microsized, m-TiO2(average particle size 153.7 nm ± 48.1 nm) and a nanosized, n-TiO2 (average particle size 18.4 nm ± 5.0 nm) have been tested. Cement paste samples (CEMI 52.5 cement, w/c=0.4) containing both photocatalysts have been evaluated based on Rhodamine B (RhB) discolouration under U.V. light, a standard test for self-cleaning cementitious materials. Experimental data are discussed in relation to photocatalyst properties (e.g.: particle size), dye adsorption and degradation characteristics. The influence of the chemical environment on photocatalyst performance and its impact on applications in construction concrete are also discussed.

In our pursuit to identify selective ligands for Bz/GABAA receptor subtypes, a novel pyrazolo[1,5-a]pyrimidine derivative (4), the azaisostere of zolpidem, was synthesized and evaluated in vitro on bovine brain homogenate and on recombinant benzodiazepine receptors (αxβ2/3γ2, x = 1−3, 5) expressed in HEK293 cells. Compound 4 displayed affinity only for α1β2γ2 subtype (Ki = 31 nM), and in an in-depth, in vivo study it revealed sedative and anxiolytic-like properties without any amnesic and myorelaxant effects in rodents.

New 3-aryl-6-(3-thienyl)pyrazolo[1,5-a]pyrimidin-7-ones (2a−j) are synthesized and evaluated in vitro on Bz/GABAA receptors and on recombinant benzodiazepine receptors (αxβ2/3γ2; x = 1−3, 5) expressed in HEK293 cells. SAR studies on the new compounds are conducted and molecular modeling is accomplished to better investigate requirements leading to subtype selectivity. Some of the synthesized compounds are tested in vivo to explore their pharmacological effect as a consequence of their high α1β2γ2 subtype selectivity observed in vitro.

The synthesis and binding study of new 8-chloropyrazolo[5,1-c][1,2,4]benzotriazine 5-oxide 3-ester compounds are reported. A pharmacological evaluation of the high-affinity ligands 1−4 belonging to the 3-heteroarylester series is made. The 3-(2-thienylmethoxycarbonyl) derivative 4 stands out from the other heteroarylesters and is found, using nine different behavioral methods, to be a functionally selective ligand in vivo:  it shows anxiolytic-like activity in the conflict models (light-dark box and plus maze test) similarly to diazepam, without any sedative and amnesic properties or interference from alcohol.

In the macro-defect-free cements (MDFs), a cross-linking of the polymer chains by Al or Ca ions coming from the hydration reactions of the cement paste may have crucial effects on the mechanical properties achieved by the final materials as well as on the material processing. In the present study, the cross-linking of poly(vinyl alcohol) (PVA) chains by Ca ions has been investigated with first-principles theoretical methods and compared with a previously investigated case of cross-linking of poly(acrylic acid) (PAA) chains. The achieved results show the existence of a Ca−PAA cross-linking that is significantly more efficient than that realized in the case of the Ca−PVA system. This result implies that the Ca−O bonds involved in the cross-linking of the PVA and PAA chains are affected by the different functional groups present in the two polymer chains and agrees with the improvement of the mechanical properties observed when the PVA polymer is replaced by the PAA polymer in Portland-cement-based MDFs. The achieved results also indicate that the Ca−polymer interactions may have significant effects on the mechanical properties of the above MDFs as well as on their processing.

The mechanical properties and microstructures of three macrodefect-free (MDF) composites, prepared from Portland and high or medium alumina cements, were evaluated. Transmission electron microscopy shows that the interface between cement grains and the polymeric matrix is porous in the case of alumina cements and pore free in the case of Portland. The analyses of the ions present in the polymeric matrix were performed by energy dispersive X-ray spectrometry, and surface free energy of the materials was estimated through dynamic contact angle measurements by using a Wilhelmy microbalance. The results suggest that Fe³⁺ and Al³⁺ ions interact differently with the polymeric matrix. This fact is also supported by dynamic mechanical thermal tests. When Portland cement is used, the microstructure of the MDF composite does not show any interphase region.

The synthesis of new 3-heteroaryl-8-chloropyrazolo[5,1-c][1,2,4]benzotriazine 5-oxides and their binding activities at the central benzodiazepine receptor (BZR) are reported. The derivatives substituted at the 3-position with electron-rich five-membered rings, such as pyrrole 11, 2-thiophene 13c, or 3-thiophene 13d, showed good affinity values for BZR. In in vivo tests the 3-(thien-3-yl)-8-chloropyrazolo[5,1-c][1,2,4]benzotriazine 5-oxide (13d) showed selective anticonvulsant activity.

Cyclization reaction of the 3‐aminopyrazoles (II) with 3‐ethoxymethylenepentane‐2,4‐dione (I) in hot ethanol yields the acetylmethylpyrazolo(1,5‐a)pyrimidines (III) which are converted into the enamines (V) by treatment with N,N‐dimethylformamide dimethyl acetal (IV).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.