Abstract The pericarp of Trapa natans L., an annual aquatic floating herb belonging to Lythraceae family, is used as a folk medicine in China. In this study, extracts of Trapa natans pericarp were tested both in vitro and in vivo through a high-fat diet with a single medium dosage streptozotocin injection induced type 2 diabetic mice. Different solvent extracts of Trapa natans pericarp showed α-amylase and α-glucosidase inhibitory activity. After four weeks administration, the ethyl acetate extract of Trapa natans pericarp (50 and 100 mg/kg b.w.) reduced fasting blood glucose level, ameliorated oral glucose tolerance and insulin resistance, improved serum lipids alterations in type 2 diabetic mice as well. Additionally, ethyl acetate extract significantly elevated the insulin receptor substrate 1 and Akt serine/threonine kinase phosphorylation compared to diabetic group. HPLC-MS and HPLC-DAD analysis showed that the ethyl acetate extract was rich in hydrolysable tannins. Results support the notion that Trapa natans pericarp extract has a potential hypoglycemic activity.

ABSTRACT Folium Eriobotryae, the dried leaves of loquat (Eriobotrya japonica, (Thunb.) Lindl., Rosaceae), is a traditional Chinese medicine used to treat cough with phlegm in China. Fallen and growing loquat leaves were tested for their effect on coughing and expectoration in mice. HPLC-ELSD and HPLC-MS analyses of aqueous and ethanol extracts of fallen or growing leaves were used to identify the chemical components responsible for this effect. Both the aqueous and ethanol extracts of growing and fallen leaves of loquat contained antitussive and expectorant activities. Moreover, an aqueous extract of growing loquat leaves with a higher flavonoid content displayed a stronger expectorant activity while the ethanol extract of fallen loquat leaves that contained a higher content of triterpenoid acids induced a stronger antitussive activity.

Neste trabalho é descrito um procedimento livre de solventes, limpo, simples e eficiente para a síntese de diidropirano[3,2-b]cromenodionas (onze derivados) a partir da reação de condensação de três componentes de ácido kójico, aldeídos aromáticos e dimedona, utilizando alume como catalisador reutilizável.

A simple, green and efficient solventless procedure for the synthesis of eleven dihydropyrano[3,2-b]chromenediones from the three-component condensation reaction of kojic acid, aromatic aldehydes, and dimedone using a reusable alum as catalyst is described.

A condensação de três componentes "one pot" de 3,4-metilenodioxifenol, aldeídos aromáticos, e ácido 1,3-dimetilbarbitúrico, eficientemente promovida na presença de Zr(HSO4)4, livre de solvente, produziu 10-aril-6,8-dimetil-6,10-diidro-5-oxa-6,8-diazaantra[2,3-d][1,3]dioxol-7,9-dionas. O método oferece diversas vantagens incluindo a simplicidade, facilidade e limpeza do procedimento extrativo, tempos de reação relativamente curtos e bons a altos rendimentos dos produtos.

A one-pot three-component condensation of 3,4-methylenedioxyphenol, aromatic aldehydes, and 1,3-dimethylbarbituric acid, efficiently promoted in the presence of Zr(HSO4)4 under solvent-free conditions, produced 10-aryl-6,8-dimethyl-6,10-dihydro-5-oxa-6,8-diazaanthra[2,3-d][1,3] dioxole-7,9-diones. The method offers several advantages including simple, easy and clean work-up procedure, relatively short reaction times and good to high yields of the products.