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.

Structure-antibacterial activity relationship of secondary metabolites from Ajuga pseudoiva Rob. leaves.

A selection of steroids, glycerides, clerodane diterpenoids, and a beta-hydroxy fatty acid methyl ester, all previously isolated from Ajuga pseudoiva leaves, were tested for their antibacterial activity toward three Gram- rods and one Gram+ coccus using the dilution method; MIC values were determined. The results suggested some importance for a free beta-hydroxy group in the fatty acid ester and also in the glycerides and clerodane derivatives; the absolute configurations of the latter, notably at C2, had little influence on activity.

Nauplathizine, a new unusual O-heteroside from Nauplius aquaticus (L).

A novel O-heteroside, (3RS,4RS)-3,4-dihydroxy-4-(2-hydroxy-5-acetylphenyl)-2-[(beta-O-glucopyranosyl)methyl]-but-1-ene (1), named nauplathizine, and a previously known compound, acetophenone-4-O-glucoside (2), were isolated from the antibacterial acetone extract of the aerial parts of Nauplius aquaticus (L) (Asteraceae, Inulae). The structure of 1 was established via its acetylated derivative by means of spectroscopic and chemical data.

7-O-6'-O-malonylcachinesidic acid, a new macrocyclic iridoid ester of malonic acid from the Tunisian plant Ajuga pseudoiva.

A new iridoid glucoside, 7-O-6'-O-malonylcachinesidic acid (1), was isolated from the leaves of Ajuga pseudoiva and characterized as its triacetyl derivative (1a). Its structure was established by spectroscopic methods and showed an unusual feature, in which an alcoholic function of the iridoid moiety and the primary alcohol of a glucopyranose unit form a 13-membered heterocycle with malonic acid.