The ability of coumarin-, flavanon- and flavonol-analogues of flavone acetic acid to stimulate human monocytes.

Flavone acetic acid (FAA) is a semi-synthetic flavonoid characterised by potent immune-modulatory and antivascular activity on mice but not in humans. Previously, the synthesis and cytotoxic activity on a human adenocarcinoma cell line of coumarin-, flavanon- and flavonol-derivatives of FAA were described. These analogues were able to induce the reduction of lysosomal neutral red uptake at 5 x 10(-5) M concentration and some of them were more effective than FAA.

New derivatives of xanthenone-4-acetic acid: synthesis, pharmacological profile and effect on TNF-alpha and NO production by human immune cells.

New derivatives of xanthenone-4-acetic acid, bearing an alkoxy chain of variable length and a basic moiety, were synthesised in order to test the influence of this additional function on antitumour activity. The introduction of bulky substituents carrying a basic nitrogen seems to be somewhat tolerated, since for some of the compounds the enhancement of lytic potential of human monocytes was comparable to that of the reference molecule DMXAA. The induction of the release of TNF-alpha and nitric oxide by human monocytes, as well as the hypothesis of a potentiation of the activity of lipopolysaccharide in the induction of those cytotoxic factors, was also evaluated.

Mono- or di-fluorinated analogues of flavone-8-acetic acid: synthesis and in vitro biological activity.

Background: Previously, the antitumour activity of some flavone-8-acetic acid (FAA) derivatives substituted with an acid function in position 2 of the benzene ring was evaluated. The most active compound resulted the one bearing a fluorine atom in position 7 of the flavone nucleus. In this paper, we evaluated new mono- or di-fluorinated FAA derivatives.

Homopterocarpanes as bridged triarylethylene analogues: synthesis and antagonistic effects in human MCF-7 breast cancer cells.

A series of new compounds structurally derived from 6a,12a-dihydro-6H,7H-[1]-benzopyran-[4,3-b]-benzopyran (homopterocarpane) was efficiently synthesized by reduction of the corresponding pyrilium salts obtained by treatment of selected flavanones and aldehydes with anhydrous HClO4. Cytotoxic effects on the human breast cancer cell line MCF-7 and antiestrogenic activity (only for compounds which resulted more active than tamoxifen (TAM)) on MCF-7 cells stimulated by 17beta-estradiol were evaluated. In vivo antiestrogenic activity and the relative binding affinity were also assessed.

Synthesis and biological evaluation of 3-alkoxy analogues of flavone-8-acetic acid.

New analogues of flavone-8-acetic acid were synthesized, bearing an alkoxy group in position 3 and different substituents on the benzene ring in position 2 of the flavone nucleus. The compounds were tested for direct cytotoxicity against four human tumor cell lines and for indirect antitumor effects by measuring their ability to enhance lytic properties of murine macrophages and human monocytes. Though direct toxicity was very low, the compounds were able to induce significant indirect toxicity.

Synthesis and antitumor activity of new derivatives of xanthen-9-one-4-acetic acid.

Xanthen-9-one-4-acetic acid (XAA) analogues in which the substituents in positions 5 and 6 are included in cyclic structures are described. Direct in vitro toxicity of the synthesized compounds against four tumor cell lines was evaluated, and their ability to stimulate mouse peritoneal macrophages and human monocytes in culture to become tumoricidal (indirect toxicity) was also studied. Despite low direct toxicity, almost all the compounds proved to be able to significantly enhance the lytic properties of both murine macrophages and human monocytes as well as the parent compound XAA and its most active derivative DMXAA taken as reference.