Cytotoxic Acetogenins from the Roots of .

, known in Mexico as "cabeza de negro" or "ilama", belongs to the Annonaceae family. Its roots are employed in folk medicine in several regions of Mexico. Taking that information into account, a chemical and biological analysis of the components present in the roots of this species was proposed.

Synthesis and in vitro antioxidant activity evaluation of 3-carboxycoumarin derivatives and QSAR study of their DPPH• radical scavenging activity.

The in vitro antioxidant activities of eight 3-carboxycoumarin derivatives were assayed by the quantitative 1,1-diphenyl-2-picrylhydrazil (DPPH•) radical scavenging activity method. 3-Acetyl-6-hydroxy-2H-1-benzopyran-2-one (C1) and ethyl 6-hydroxy-2-oxo-2H-1-benzopyran-3-carboxylate (C2) presented the best radical-scavenging activity. A quantitative structure-activity relationship (QSAR) study was performed and correlated with the experimental DPPH• scavenging data.

3-(Piperidin-1-ium-1-yl)-6-azoniaspiro-[5.5]undecane dibromide monohydrate.

The title compound, C(15)H(30)N(2) (2+)·2Br(-)·H(2)O, was synthesized by reaction of 4-piperidino-piperidine with dibromo-pentane. The dication is built up from three linked piperidine rings, two of which have one quaternary N atom in common (azoniaspiro), whereas the third is N-C bonded to the azoniaspiro system and protonated on the N atom (piperidinium). All three piperidine rings adopt chair conformations.

Antioxidant activity of butyl- and phenylstannoxanes derived from 2-, 3- and 4-pyridinecarboxylic acids.

In vitro antioxidant activity for 12 stannoxanes derived from Ph(3)SnCl (compounds 1-3), Ph(2)SnCl(2) (compounds 4-6), Bu(3)SnCl (compounds 7-9), and Bu(2)SnCl(2) (compounds 10-12), was assayed qualitatively by the chromatographic profile with 1,1-diphenyl-2-picrylhydrazil (DPPH) method and by two quantitative methods: the DPPH radical scavenging activity and Ferric-Reducing Antioxidant Power (FRAP) assays. The results were compared with those obtained with the starting materials 2-pyridine- carboxylic acid (I), 3-pyridinecarboxylic acid (II) and 4-pyridinecarboxylic acid (III), as well as with standard compounds, such as vitamin C and vitamin E, respectively. The in vitro antiradical activity with DPPH of diphenyltin derivative 5 showed a very similar behavior to vitamin C at a 20 microg/mL concentration, whereas according to the FRAP method, compound 8 was better.