81 documents found, page 1 of 9

Synthesis and Evaluation of Biocide and Cetane Number Improver Additives for Bi...

Biodiesel demand is increasing all over the world and the inhibition of microbial growth during the storage of this biofuel is extremely important. There are few studies involving the evaluation of biocides specifically for biodiesel. In the present work, we synthesized and evaluated a set of biocide candidates from chemical transformations in triacylglycerides. Samples of pure biodiesel with the products were ...

Chemical Constituents of Psychotria nemorosa Gardner and Antinociceptive Activity

Through dereplication strategies using gas chromatography-mass spectrometry (GC-MS) and ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS), the ethanol extract from Psycotria nemorosa leaves (Rubiaceae) showed to be composed of: cinnamic acid, dihydroactinidiolide, 4-hydroxy-β-ionone, phytol, isophytol, 4,8,12,16-tetramethylheptadecan-4-olide, lupeol, a mixture of α/β-amyrin, the keto and ac...

First Asymmetric Reduction of Isatin by Marine-Derived Fungi

In this study, whole cells of marine-derived fungi were used to reduce isatin (1H-indole-2,3-dione) to dioxindole (3-hydroxyindolin-2-one) for 7 days at 32 °C. The screening showed that several strains could reduce isatin and produce the enantioenriched dioxindole. The best conversions were obtained by Cladosporium sp. CBMAI 1237 and Westerdykella sp. CBMAI 1679, however, the best enantiomeric excess was obtain...

Evaluating the Potential of Biodiesel Production through Microalgae Farming in ...

In the last decade, the research works on microbial as a potential source of lipid for biodiesel production have been growing. In this work, the potential of a sludge from high-rate lagoons in urban sewage treatment, composed mainly by Chlorella sp., as oil source for biodiesel production, was studied. The potential of Chlorella sp. growth in photobioreactor under controlled conditions was also investigated. Lo...

Anti-Trypanosoma Activity and Synergistic Effects of Natural and Semi-Synthetic...

Chagas' disease is a parasitic disease with unsatisfactory treatment, mainly in chronic stage. This study aimed to evaluate the trypanocidal activity and action mechanisms of α/β-amyrin and its semi-synthetic derivatives, together with four isolated natural triterpenes, tested against trypomastigote and amastigote forms. The structure-activity relationship was suggested and cytotoxicity was measured. In general...

The Genus Psychotria: Phytochemistry, Chemotaxonomy, Ethnopharmacology and Biol...

Psychotria genus (Rubiaceae) is featured into the angiosperm, being the most speciose genus comprising approximately 1600 species. The available references demonstrate that Psychotria has several uses on traditional medicine including spiritual and cultural purposes, and presents great potential on pharmacological properties, especially the one related to neurodegenerative diseases. Despite its wide biological ...

Ultrasound-Assisted Synthesis of Isatin-Type 5'-(4-Alkyl/Aryl-1H-1,2,3-triazole...

This short report describes the preparation of twelve isatin derivatives, 5'-(4-alkyl/aryl-1H-1,2,3-triazoles), using 5-azido-spiro[1,3-dioxolane-2,3'-indol]-2'(1'H)-one in the presence of various alkynes under acidic conditions and ultrasound irradiation. Compared with conventional methods, yields increased to 78-98%, and reaction times decreased to 5 min. Besides time and energy saving, there was no need for ...

RESSONÂNCIA MAGNÉTICA NUCLEAR DE SUBSTÂNCIAS ORGANOFLUORADAS: UM DESAFIO NO ENS...

Nuclear magnetic resonance is a technique that is widely used for elucidating and characterizing organic substances. Organofluorine substances have applications in many areas from drugs to liquid crystals, but their NMR spectra are often challenging due to fluoride coupling with other nuclei. For this reason, NMR spectra of this class of substances are not commonly covered in undergraduate and graduate chemistr...

Journal of the Brazilian Chemical Society: 25 years of success

Desafios da indústria farmacêutica brasileira

The paper traces a panorama of the development of new drugs and hopes to contribute for Brazil to become a player in the discovery of new drugs. Brazil is the sixth world market retail consumer of medicines prone to expansion, has a pharmaceutical industry focused on the production of generics and a very large number of undergraduate courses in Pharmacy. The national industry has grown over the last decade afte...