A síntese e o perfil anti-inflamatório e analgésico dos novos agentes isocromanilacetilarilidrazônicos são descritos neste artigo. A rota sintética utilizada neste trabalho explora como passo chave para a construção de um anel heterocíclico de seis membros, a ciclização catalisada por um ácido de Lewis, que representa uma modificação da reação de Friedel-Crafts. Estes novos derivados (3) são obtidos em ca. de 85% de rendimento, a partir do safrol (4) utilizado como produto natural abundante, isolado do óleo de Sassafrás. A análise dos espectros de RMN destes novos derivados indica a natureza diastereoisomérica a nível da ligação C=N, na razão de 70:30, onde a maior contribuição é relativa ao isômero (E). Os resultados obtidos da avaliação farmacológica de (3) no teste do edema de pata de rato induzido por carragenina e no teste de contorções abdominais induzidas pelo ácido acético, indicam a natureza farmacofórica da unidade acilidrazona para a atividade analgésica observada nesta série. O papel dos substituintes na sub-unidade arila na atividade farmacológica parece indicar que a presença de grupos hidrofóbicos podem elevar o perfil analgésico. Estes novos derivados isocromanilacetilarilidrazônicos (3) representam nova classe de agentes analgésicos não-convencionais.The synthesis and pharmacological profile as analgesic and anti-inflammatory agents of new isochromanylacetylarylhydrazone derivatives (3) are described in this paper. The synthetic route used in this work to construct the heterocyclic six member ring explored a Lewis acid-catalyzed cyclization process as the key step, which represents a modified Friedel-Crafts reaction. These new derivatives (3) were obtained in ca. 85 % overall yields from the starting material safrole (4), an abundant natural product isolated from Sassafras oil. The NMR spectral analysis of these new derivatives indicated, at the C=N double bond level, the diastereomeric nature in a 70:30 ratio, where the major compound is the (E)-isomer. The results obtained from the pharmacological evaluation of (3) using the carrageenan-induced rat paw edema test and the acetic acid solution-induced constrictions in mouse test, indicated the pharmacophoric nature of the acylarylhydrazone moiety to the analgesic activity observed in this series.The role of the aryl substituents in the bioactivity seems to indicate that the presence of hydrophobic groups may improve the analgesic profile. These new isochromanylacetylarylhydrazone derivatives (3) represent a new class of non-addictive analgesic agents.

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Under the renewable energy context, sugarcane biomass pyrolysis has been growing as a convenient route to produce bio-oil, which can be set into the chemical industry and refineries as building blocks or combustion fuel. In this work sugarcane straw was submitted to direct pyrolysis in a fluidized bed pilot plant at 500˚C, in presence of air. Sugarcane in natura was also pyrolysed as a model for comparison, in order to determine the viability of processing different sources of raw biomass. The physicochemical characterization of the biomass precursors as well as of the bio-oils was also carried out, which points both biomass feedstocks as suitable for bio-oil production in terms of viscosity, surface tension, density and acidity. The bio-oil obtained from sugarcane in natura presented higher carbon and hydrogen content as well as lower oxygen content. On the other hand, the metal content is higher in the bio-oil obtained from sugarcane straw, in special the iron and potassium contents were 807 ppm and 123 ppm against 27 ppm and 1 ppm in the bio-oil from sugarcane in natura. Aliphatic and aromatic compounds as well as carbohydrates scaffolds were identified as the main components of the bio-oil. GC-MS analyses showed aromatic products from lignine fragmentation and free sugars and sugar derivatives.

Second-generation biomass has been proposed as an alternative way to provide sustainable energy. However, the transformation of biomass into liquid by thermoconversion introduces several drawbacks in the bio-oil. A new approach to convert biomass into a more stable and less polar biocrude compared to fast pyrolysis bio-oil was recently developed, which is based on hydrolysis/functionalization of biomass carbohydrates. This work describes the transformation of sugar cane bagasse and Jatropha curcas cake in biocrude through the acetylation reaction under microwave radiation, in the presence of acetic anhydride and a catalytic amount of sulfuric acid. The reaction conditions were broadly investigated and moderate to complete conversion of the biomasses was achieved; however, Jatropha curcas was more resistant than sugar cane to the hydrolysis/ acetylation reaction. The produced biocrudes were thoroughly characterized, and polyacetylated carbohydrates were the main products identified.

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