No abstract

In this study 10 guaianolide-type sesquiterpene gamma-lactones named amphoricarpolides, isolated from the aerial parts of two endemic subspecies of Amphoricarpos neumayeri (ssp. neumayeri and ssp. murbeckii Bosnjak), were investigated by means of reversed-phase thin-layer chromatography. Methanol-water and tetrahydrofuran-water binary mixtures were used as mobile phase in order to determine lipophilicity parameters R (0) (M) and C(0). Some of the investigated compounds were screened for their cytotoxic activity against HeLa and B16 cells. Chromatographically obtained lipophilicity parameters were correlated with calculated logP values and IC(50) values. Principal component analysis identified the dominant pattern in the chromatographically obtained data.

Cytotoxic activity of four series of coordinated complexes of Zn(II) and Fe(II) with hydrazone/hydrazide ligands against HeLa and B16 cells was evaluated. The ligands N’,N'2- bis[(1E)-1-(2-pyridyl)ethylidene]ethanedihydrazide (H2L1) and N’,N'2-bis[(1E)-1-(2-pyridyl) ethylidene]propanedihydrazide (H2L2) and their Zn(II) complexes showed IC50 values in the low micromolar range, while the other ligands and complexes were less active or inactive.

Organometallic Cd(II) compounds have recently attracted attention for their anticancer activity. The interaction of the dinuclear complex of Cd(II) with the condensation product of 2-acetylpyridine and malonic acid dihydrazide, N',N'(2) -bis[(1E)-1-(2-pyridyl)ethylidene]propanedihydrazide (Cd(II)H(2) L), with calf thymus DNA (CT-DNA) was monitored by blue shift in UV-vis spectra of the complex. The binding constant of Cd(II)H(2) L complex with CT-DNA was determined (K(B) = 1.8 × 10(4) M(-1) ) and was indicative of minor groove binding. Agarose gel electrophoretic changes in mobility of supercoiled and circular forms of pBR322 and pUC18 plasmids in the presence of the complex suggest that conformational changes in the plasmids occur upon binding of the Cd(II)H(2) L complex. The Cd(II)H(2) L complex induced perturbation of the cell cycle phase distribution and an increase in the percentage of cells in the sub-G1 phase of human cervical cancer HeLa cell line and murine melanoma B16 cell line. Immunoblotting analysis showed the overexpression of Bcl-2 protein with the Cd(II)H(2) L complex.

Two epimeric guaianolides were isolated from the aerial parts of Anthemis segetalis. These compounds have not been detected in any Anthemis species so far. One of them was tested for cytotoxicity against human cervical cancer (HeLa) and murine melanoma (B16) cell lines showing appreciable activity.