Semi-synthesis of new antimicrobial esters from the natural oleanolic and maslinic acids.

In this article, we report an effective procedure for the selective isolation of oleanolic acid 1 and maslinic acid 2 (3.4 and 8.5mg/g DW, respectively) from pomace olive (Olea europaea L.

New septanoside and 20-hydroxyecdysone septanoside derivative from Atriplex portulacoides roots with preliminary biological activities.

The phytochemical investigation of a Tunisian plant Atriplex portulacoides (Chenopodiaceae) led to the isolation of two new compounds designated as portulasoid (2) and septanoecdysone (3) along with the known 20-hydroxyecdysone (20HE) (1). Their chemical structures were elucidated on the basis of extensive spectroscopic methods including ES-HRMS, 1D and 2D-NMR. The isolated compounds were finally tested for their antioxidant activity by using DPPH, ABTS(+), Fe(3+) and catalase assays and also for their antibacterial and anticholinesterase activities.

New antioxidant bibenzyl derivative and isoflavonoid from the Tunisian Salsola tetrandra Folsk.

Two new phytochemical compounds, Tetranins A and B, 1-(3,5'-dihydroxy-4'-méthoxyphenyl)-2-phenylethanol 1 and 5,2'-dihydroxy-5'-methoxy-6,7-methylenedioxy-isoflavone 2, were isolated from the EtOAc extract of Salsola tetrandra roots. They exhibited a significant antioxidant effect in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assays. Their structures were elucidated by extensive spectroscopic methods including 1-D-((1)H and (13)C) and 2-D-NMR experiments (CHcorr, HMBC, (1)H-(1)H COSY and NOESY) as well as high-resolution ES-MS and they were found to be quite active as antioxidants in the DPPH and ABTS assays.