3-Halochromones Through Oxidative α-Halogenation of Enaminones and its Photophysical Investigation: Another Case of Photo-induced Partially Aromatised Intramolecular Charge Transfer?

A versatile synthesis strategy for fluorescent 3-halo-4H-chromen-4-one derivatives is reported. The method involves the oxidative α-halogenation of enaminones performed by an efficient and sustainable oxidation system. The use of Oxone® in combination with KCl, KBr, or KI enables the preparation of 3-chloro-, 3-bromo-, or 3-iodo-4H-chromen-4-one in good to excellent yields, with great functional group tolerance where the protocol is amenable to gram-scale synthesis. The analysis of the photophysical properties of the presented 4H-chromen-4-one showed absorption in the UV region and fluorescence emission in the violet-to-cyan region with a relatively large Stokes shift. In solution, all compounds present a dual fluorescence emission, regardless of the solvent, assigned to a partially aromatised intramolecular charge transfer mechanism, considering the presence of a pseudo-aromatic ring in the chromone scaffold and the absence of the influence of substituent electronic features in optical behaviour.

The potential exploitation of the Malay-red apple (Syzygium malaccense) seed as source of a phosphorylated starch.

This work presents the characterization of a novel naturally phosphorylated starch extracted from an unconventional and non-utilized source, the seeds of the stone fruit Syzygium malaccense. The morphology and chemical characteristics of the extracted starch were examined by scanning electron microscopy, FTIR, 1H/13C/31P NMR and 13C-CP/MAS-NMR, HPAEC-PAD chromatography, XRD, DSC, and RVA. The extraction yielded a highly pure starch (95.6 %) with an average granule size of 13 µm. The analysis of the starch components revealed an amylose content of 28.1 % and a predominance (65 %) of B-chains (B1-B3 65 %) in the amylopectin, as shown through HPAEC-PAD chromatography. The X-ray diffractogram was compatible with B-type starch, which was confirmed by the deconvolution of the C1 peak in the 13C-CP/MAS-NMR. X-Ray diffractogram also showed that S. malaccense has 28.5 % of crystallinity. DSC analysis showed values of 82.6 °C and -12.41 J g-1 for Tc and ΔH, respectively, which is compatible with a highly ordered starch granule structure. The values observed for peak (4678 mPa•s), trough (3055 mPa•s), and final viscosity (6526 mPa•s) indicated that S. malaccense may be used as a thickener in hot food.

Chemotaxonomic significance of flavonoids, coumarins and triterpenes of Augusta longifolia (Spreng.) Rehder, Rubiaceae-Ixoroideae, with new insights about its systematic position within the family / Significância quimiotaxômica de flavonoides, cumarinas e triterpenos de Augusta longifolia (Spreng.) Rehder, Rubiaceae-Ixoroideae, com novos entendimentos sobre a posição sistemática dentro da família

Augusta has traditionally been placed in the tribe Rondeletieae, subfamily Cinchonoideae. However, recent molecular phylogenies positioned it near to Wendlandia (Ixoroideae), but locate A. longifolia near to the clade Ixoroidinae II. The study of A. longifolia afforded two coumarins, five flavonoids, three triterpenoids and one benzoic acid derivative. These metabolites reinforce the separation of Augusta as a monospecific genus, and Lindenia as a genus of three species, closely related to Wendlandia.

Augusta tem sido tradicionalmente colocada na tribo Rondeletieae, Cinchonoideae subfamília. No entanto, recentes filogenias moleculares posicionou-a perto de Wendlandia, porém localizando A. longifolia perto do clado Ixoroidinae II. O estudo de A. longifolia resultou em duas cumarinas, cinco flavonoides, três triterpenoides e um derivado do ácido benzóico. Estes metabolitos reforçam a separação da Augusta como um gênero monoespecífico, e Lindenia como um gênero de três espécies, intimamente relacionada com Wendlandia.

Analgesic and anti-inflammatory effects of Cheiloclinium cognatum root barks

Cheiloclinium cognatum (Hippocrateaceae) has been used in folk medicine to treat fever and edema. In this paper, we report the anti-inflammatory and analgesic activities of the crude dichloromethane extract (DECc) from C. cognatum root barks collected in Auguste de Saint Hilaire wood at Universidade Federal de Goiás. Doses of 0.1, 0.3 and 1.0 g/kg caused a dose-dependent inhibition of croton oil-induced ear edema in mice equivalent to 21, 30 and 51 percent, respectively. There was a significant increase in analgesic-meter-induced tail flick test equivalent to 105, 189 and 200 percent of increase tail flick reaction time. These results allowed to suggest that C. cognatum could be a source of new compounds which anti-inflammatory and analgesic activities.

Cheiloclinium cognatum é uma planta da família das Hippocrateaceae, popularmente conhecida como bacupari, usada popularmente no tratamento de febre e edemas. Neste artigo, descrevemos as atividades antiinflamatória e analgésica do extrato bruto diclorometânico das cascas das raízes (DECc), coletadas no bosque Auguste de Saint Hilaire, localizado na Universidade Federal de Goiás. Doses de 0,1, 0,3 e 1,0 g/kg causaram uma redução de 21, 30 e 51 por cento, respectivamente, no edema de orelha de camundongos, induzido pelo óleo de cróton. No método algesimétrico, flexão de cauda, observou-se um significativo aumento no tempo para reação ao estímulo térmico equivalente a 105, 189 e 200 por cento. Estes resultados sugerem que C. cognatum pode ser uma fonte de novos compostos com atividades antiinflamatória e analgésica.