Gláucia B. C. A. Slana

Total syntheses of oxygenated brazanquinones via regioselective homologous anionic Fries rearrangement of benzylic O-carbamates

Using new variations of anionic aromatic chemistry, the total synthesis of oxygenated brazanquinones (1a-1c), derived from β-brasan, a natural product isolated from Caesalpina echinata, via carbamates 2a-2c is described.

Chemical and Biological Aspects of the Essential Oil of Indian Cloves

The Indian clove (Syzygium aromaticum, Myrtaceae) is a well appreciated spice since the ancient times not only by its flavor and culinary qualities, but also because of its therapeutic uses. Several popular and traditional applications have been reported in literature as well as numerous scientific studies on its activities. In this work we present a synopsis and discussion on S. aromaticum to provide the readers some useful information on the historical aspects, the chemical composition and its large variety of potential applications for the treatment of a number of illnesses.

Quantification and Characterization of the Main Components of the Ethanolic Extract of Indian Cloves,Syzygium aromaticum[I] Merr. et Perry

The Indian clove, Syzygium aromaticum [L] Merr. et Perry, has been popularly used in the treatment of several diseases. A more recent use of this spice in Brazil is a homemade formulation, based on the ethanolic extraction of the dried flower buds of S. aromaticum, which has shown to be efficient as mosquitoes repellent. Here we evaluated, through the development of a GC analytical technique, the concentrations of the main components of the ethanolic extract of Indian cloves (eugenol and eugenyl acetate), and possible responsible for the repellent activity, in this homemade formulation. Our results corroborated the efficiency of this protocol to extract eugenol and eugenyl acetate and established the ideal conditions for extraction.

Preliminary study of insect attraction by a mixture of semiochemicals containing 1,2,4-Trimethoxybenzene in domestic citric-culture

In this work we describe a new efficient strategy for the preparation of 1,2,4-trimethoxybenzene (3) in 56% overall yield. The compound 3 was used in a preliminary study of insect attraction by a mixture of semiochemicals called TIV, composed of indol (1), vanillin (2) and 1,2,4-trimethoxybenzene (3), in eight Mc Phail style traps installed at a domestic orchard of citric-culture, containing 120 trees not infected by plagues in Bom Jesus Farm, located next to a patch of the Atlantic Forest, at Silva Jardim, Rio de Janeiro, Brazil.

Synthesis of 1,2,4-Trimethoxybenzene and Its Selective Functionalization at C-3 by Directed Metalation

Abstract A new and efficient strategy was developed for the preparation of 1,2,4-trimethoxybenzene (3, a powerful attractant of Euglossini bees) and its C-3 derivatives (7a–j), from vanillin (2) in 56% overall yield.

Assessing Drug-Excipient Interactions in the Formulation of Isoniazid Tablets

A suitable and efficient high-performance liquid chromatography (HPLC) method was developed for the simultaneous determination of tuberculostatic isoniazid and its related impurities, isonicotinic acid and isonicotinamide, in oral solid dosage forms. We studied the influence on chromatographic separation of mobile phase parameters, such as pH, ion pairing and ionic strength, as well as column bonded phase and brands. The use of buffer solution pH 6.8:acetonitrile 96:4 (v/v) at 0.8 mL min-1, C18 column (250 × 4.6 mm, 5 µm), allowed proper separation of these ionizable analytes without the need of ion pairing agents. The limit of quantification of the method (0.1 µg mL-1) was suitable for the analysis of impurities. A drug-excipient compatibility study was carried out with the anaytical method proposed in this work and addressed frequent excipients used in isoniazid coated tablets. The dye FD&C blue 2 lake promoted the highest degradation of the tuberculostatic agent.