Synthesis and biological properties of new alpha-methylene-gamma-butyrolactones and alpha,beta-unsaturated delta-lactones.

The synthesis of a series of alpha-methylene-gamma-butyrolactones (compounds 4a, 4b, 6-12, 16, 17) and alpha,beta-unsaturated-delta-lactones (compounds 19-23, 25, 26) starting from 4,4-dimethyldihydrofuran-2,3-dione (1) has been described. Their chemical structures were assigned by spectroscopic evidence. These new compounds exhibited significantly different antiproliferative properties against cultured human tumor cell lines with their IC(50) values ranging from 0.

Free exchange across cells, and echistatin-sensitive membrane target for the metastasis inhibitor NAMI-A (imidazolium trans-imidazole dimethyl sulfoxide tetrachlororuthenate) on KB tumor cells.

The duration of cell proadhesive effects induced by imidazolium trans-imidazole dimethyl sulfoxide tetrachlororuthenate (NAMI-A), a compound endowed with in vivo antimetastatic properties, was tested in vitro on the human epithelial tumor cell line KB. The intensity of proadhesive effects continues to increase up to 48 to 72 h after NAMI-A withdrawal and declines only after 96 h. The proadhesive effect on cells seeded on fibronectin is greater than on plastic, since it already reaches its maximum after 24 h.

Actin-dependent tumour cell adhesion after short-term exposure to the antimetastasis ruthenium complex NAMI-A.

Imidazolium trans-imidazoledimethylsulphoxidetrachlororuthenate (NAMI-A) was tested in vitro on the pro-adhesive properties, evaluated as resistance to trypsin treatment, which is a bona fide measure of adhesion strength, of KB and HeLa carcinoma cell lines and on human polymorphonuclear neutrophils (HPMN). NAMI-A increased the pro-adhesive activity of KB cells at 0.001 mM concentration, after few minutes incubation and this effect was not influenced by the vehicle used for cell challenge, neither did it depend on NAMI-A concentration or on temperature.

Preliminary biological assay on cerebroside mixture from Euphorbia nicaeensis All. Isolation and structure determination of five glucocerebrosides.

Preliminary studies of in vitro cytostatic activity on less polar fraction of the MeOH extract of the plant Euphorbia nicaeensis All., carried out on KB cells, have evinced a relatively low ability of extract to inhibit cell growth. Successive, five glucocerebrosides were isolated from the cerebroside molecular species obtained from this extract using normal and reversed phase column 'flash-chromatography'.

Synthesis, characterization and antitumor activity of platinum(II) complexes with diethyl and monoethyl 2-quinolylmethylphosphonates.

A series of new platinum(II) complexes with diethyl (2-dqmp) and monoethyl (2-Hmqmp) 2-quinolylmethylphosphonates have been prepared and studied. Both organophosphorus ligands by reaction with [PtX(4)](2-) (X=Cl, Br) form either the molecular or ionic complexes depending on the acidity of the reaction solution. Dihalide adducts, trans-[PtL(2)X(2)] (L=2-dqmp, 2-Hmqmp), with N-bonded ligand through the quinoline nitrogen were obtained in the neutral medium, while under acidic conditions at pH<3 were isolated the ion-pair salt complexes, [LH](2)[PtX(4)], containing the protonated quinoline ligand as cation and tetrahaloplatinate complex as anion.