Efficient acetaldehyde production and recovery upon selective Cu/TiO2-photocatalytic oxidation of ethanol in aqueous solution

The depletion of fossil chemicals and energy sources led to develop processes allowing the conversion of renewable feedstocks into useful products. Bioethanol production is a typical case of biomass conversion into chemical species with attractive uses, such as fuel, fuel additives, or chemical intermediates. In the present work, the possibility to produce acetaldehyde through Cu/TiO2 photocatalytic oxidation in liquid phase with aqueous mixtures at ethanol concentrations comparable to those of biorefinery outlet streams was assessed for the first time. The effect of cupric ion concentration on acetaldehyde selectivity was investigated. A nearly unit value of acetaldehyde selectivity was observed for a starting cupric ion concentration of 120 mM. The recovery and purification of acetaldehyde were performed by removing acetaldehyde from the solution through an inert gas bubbling and feeding the outgoing gaseous mixture to an absorber, in which acetaldehyde was captured by an aqueous stream. The possibility to regenerate the photocatalytic system in situ via zerovalent copper reoxidation was evaluated. In view of full-scale implementations, a careful flammability analysis of the resulting ternary mixture (ethanol/oxygen/nitrogen) along with a feasible process flow sheet were proposed. The possibility to employ bioethanol streams from biorefinery, sunlight irradiation as energy source, water as solvent, mild operating conditions, and low-cost, non-toxic, and reusable photocatalyst, makes the process investigated an attractive example of the eco-green synthesis of valuable commodity chemicals

ANTIFUNGAL AGENTS .8. SYNTHESIS AND ANTIFUNGAL ACTIVITIES OF BIPYRRYL ANALOGS OF BIFONAZOLE

Various bipyrryl analogues of bifonazole were synthesized starting from aryl-3-pyrryl-1-imidazolylmethanes. The introduction of a second pyrryl portion was performed by linking an acrylate moiety at 1-position of the pyrrole ring and then by treatment with TosMIC. The bipyrryl esters were hydrolyzed and decarboxylated to afford the required imidazoles. All new imidazole derivatives were tested against Candida albicans and Candida spp using as standard controls miconazole, bifonazole and ketoconazole

Antifungal agents. III. Naphthyl and thienyl derivatives of 1H-imidazol-1-yl-4-phenyl-1H-pyrrol-3-ylmethane.

The in vitro antifungal activities of some naphthyl and thienyl derivatives of 1H-imidazol-1-yl-4-phenyl-1H-pyrrol-3-ylmethane against Candida albicans and Candida spp are reported. The title derivatives were prepared starting from proper arylstirylketones, which were reacted with tosylmethylisocyanide (Tos-MIC) to afford the related 4-phenyl-1H-pyrrol-3-yl aryl ketones. Reduction of ketones to the corresponding carbinols followed by treatment of the last compounds with 1,1'-carbonyldiimidazole (CDI) gave the title imidazoles. The related N-methylpyrrole derivatives are also describe

Antifungal Agents. 9. 3-Aryl-4-[a-(1H-imidazol-1-yl)arylmethyl]pyrroles: A New Class of Potent Anti-Candida Agents.

A new class of potent antifungal agents, namely, 3-aryl-4-[a-(1H-imidazol-l-yl)arylmethyllpyrroles, is described. These compounds are related to bifonazole and pyrrolnitrin, two compounds belonging to the class of antimycotic drugs. The synthesis of the title pyrroles has been performed starting from 1,3-diaryl-2-propen-l-onews,h ich were reacted with tosylmethyl isocyanide to give 3-aroyl-4-arylpyrroles. Reduction of the resulting compounds by lithium aluminum hydride furnished the related alcohols, which were treated with 1,l’-carbonyldiimidazole to afford the required imidazole derivatives. Forty-four new pyrroles which incorporate an (arylmethy1)imidazole moiety in the 3-arylpyrrole structure were prepared by the above procedure and tested in vitro against Candida albicans and Candida spp. Among test compounds, 10 were found to be highly active against C. albicans. The most active derivative (27) was twice as potent (MICgo) as bifonazole, and its activity was 4 times greater than those of miconazole and ketoconazole. The other nine compounds showed antifungal activity of-the same order of that of bifonazole and were ca. 2 times as active as miconazole and ketoconazole. Derivatives 21 and 27 tested in vivo against C. albicans A170 were shown to be highly effective in rabbit skin candidosis. Pharmacological studies on compounds 27 and other related pyrroles (19, 35, 36, 38, 39, and 49) are in progress to select one of them as a potential candidate for clinical experiments

Costruire la pace tra Stato e territori: i dilemmi del peacebuilding

I capitoli in questo volume confermano e approfondiscono un aspetto noto nella letteratura specialistica, e cioè che il ruolo degli attori internazio- nali nel sostenere la liberalizzazione economica e politica sia stato contrad- dittorio e talvolta deludente.2 A fronte di un’enfasi posta sulla necessità di promuovere la democrazia, le organizzazioni internazionali hanno spesso 1 Si veda, ad esempio, Roland Paris, At War’s End: Building Peace After Civil Conflict, Cam- bridge, Cambridge University Press, 2004. 2 Anna Jarstad e Timothy D. Sisk (a cura di), From War to Democracy: Dilemmas of Peace- building, Cambridge, Cambridge University Press, 2008; Roland Paris e Timothy D. Sisk (a cura di), The Dilemmas of Statebuilding: Confronting the Contradictions of Postwar Peace Operations, London, Routledge, 2009. Introduzione 17 18 Costruire la pace tra Stato e territori imposto in maniera verticistica, e talvolta persino autocratica, le proprie priorità economiche e politiche. Nel tentare di sostenere la costruzione e il consolidamento delle istituzioni politiche locali, gli attori internazionali hanno frequentemente fornito legittimità a protagonisti locali responsabili di crimini e malversazioni. Di più, la promozione di un’economia di mercato ha favorito la svendita di industrie nazionali a mafiosi oppure a potentati economici internazionali con scarso beneficio per la popolazione locale. Non sorprende, quindi, che il tipo di società che emerge nelle zone di crisi e conflitto sia spesso assai distante dagli standard promossi, almeno in linea di principio, dall’azione internazionale. Le istituzioni locali hanno una par- venza di democraticità, ma sono regolarmente percepite come illegittime e inefficaci dai cittadini di quei Paesi. Le minoranze etniche e nazionali continuano a essere oggetto di discriminazione, nonostante la presenza di legislazioni in linea con gli standard internazionali sui diritti umani e le libertà civili e politiche. L’economia ha talvolta vissuto un revival, sostenuto anche dagli aiuti internazionali, ma non è di norma in grado di soddisfare i bisogni della popolazione