in multi-step organic syntheses, the protection and deprotection of tetrahydropyranyl (thp) ethers is one of the most frequently used methods. over the years, different methods have been used from various catalytic systems for the protection of hydroxyl groups as thp ethers and their deprotection. herein we have reported that various alcohols and phenols have been efficiently converted to the c...

Representative species of the Taxus genus, known since antiquity for their toxicity, have been an essential plant resource production extracts with medicinal properties (anti-inflammatory, antifungal, and antibacterial) and, more recently, study allelopathic significant implications in organic agriculture (bioherbicidal potential). With a view to development this new direction research, present...

Abstract Lychee (Litchi chinensis Sonn.) is an exotic fruit from Asia, recently introduced in Europe. With the increase world production of this fruit, many by-products are wasted during industrial processing, including their peels and seeds. Considering utilization as edible material a new functional ingredient, work aimed to assess nutritional phytochemical characterization, well antioxidant ...

Two new alcoholic aroma precursors, cis- and trans-linalool, 3,7-oxides 6-O-beta-D-apiofuranosyl-beta-D-glucopyranosides (1 and 2), as well as two already known compounds, (Z)-3-hexenyl beta-D-glucopyranoside (3) and methyl salicylate 6-O-beta-D-xylopyranosyl-beta-D-glucopyranoside (beta-primeveroside: 4), and another new monoterpendiol glycoside, 8-hydroxygeranyl beta-primeveroside (5) have re...

A novel β-lactam derivative, albactam, was isolated from the alcoholic extract of the flowers of Albizia lebbeck. It showed a significant anti-aggregatory activity against adenosine diphosphate and arachidonic acid induced guinea-pigs' platelets aggregation in vitro. Six more known compounds were also isolated and fully characterized by measuring 1D and 2D NMR, two of them are the triterpenes β...

Ferula gummosa Boiss is a good source of biologically active compounds such as monoterpene and sesquiterpene derivatives. There are also several reports on antioxidant effects of these compounds. The aim of this study was to investigate the effect of daily administration of F. gummosa root hydro-alcoholic extract on serum oxidant-antioxidant status. Twenty four Wistar rats were randomly divided...

The DPPH radical scavenging activity of 2',4',6'-trihydroxy- and 2'-hydroxy-4',6'-dimethoxychalcones carrying a 2,3- and 3,4-dihydroxylated, and 3,4,5-trihydroxylated B-ring was evaluated in alcoholic and non-alcoholic solvents. All test compounds scavenged more than two equivalent of radicals by a possible conversion to the corresponding B-ring quinones and in most cases subsequently underwent...

Beaumontia grandiflora Wall. (Apocynaceae) is an ornamental plant cultivated in Egypt. Investigation of the chemical constituents of the aerial parts of B. grandiflora Wall. in pet. ether extract led to isolation and identification of twelve fatty acids in which linoleic acid (29.60%) and Palmitic acid (19.12%) are the main acids. The unsaponifiable fraction was found to contain a series 14 27 ...