Concomitant and controlled release of furazolidone and bismuth(III) incorporated in a cross-linked sodium alginate-carboxymethyl cellulose hydrogel.

The combination of bismuth(III) citrate and the antibiotic furazolidone (FDZ) results in a synergetic effect on Helicobacter pylori eradication. However, the problems associated with their oral administration are challenges to overcome. Thus, in the present study, sodium alginate (SA)/carboxymethyl cellulose (CMC) blend hydrogels (SC) were developed for concomitant and controlled release of furazolidone and bismuth(III).

Synthesis and phytotoxic activity of new pyridones derived from 4-hydroxy-6-methylpyridin-2(1H)-one.

Commercial dehydroacetic acid was converted into 4-hydroxy-6-methylpyridin-2(1H)-one (3), which was then condensed with several aliphatic aldehydes to produce seven new title compounds in variable yields (35-92%). Reaction of 3 with alpha,beta-unsaturated aldehydes resulted in the formation of condensed pyran derivatives 4g' and 4h'. A mechanism is proposed to explain the formation of such compounds.

Preparation of achiral and chiral (E)-enaminopyran-2,4-diones and their phytotoxic activity.

A short and efficient approach to a range of new chiral and achiral functionalized (E)-enaminopyran-2,4-diones starting with commercially available dehydroacetic acid is described. The phytotoxic properties of these (E)-enaminopyran-2,4-diones were evaluated by their ability to interfere with the growth of Sorghum bicolor and Cucumis sativus seedlings. A different sensitivity of the two crops was evident with the (E)-enaminopyran-2,4-diones.

Anatomical and histochemical characterization of extrafloral nectaries of Prockia crucis (Salicaceae).

Besides being vital tools in taxonomic evaluation, the anatomy of plant secretory structures and the chemical composition of their secretions may contribute to a more thorough understanding of the roles and functions of these secretory structures. Here we used standard techniques for plant anatomy and histochemistry to examine secretory structures on leaves at different stages of development of Prockia crucis, to evaluate the origin and development of the structures, and to identify the disaccharides and monosaccharides in the exudates. Fructose, glucose, and sucrose constituted up to 49.