Tetraspanins: useful multifunction proteins for the possible design and development of small-molecule therapeutic tools.

Tetraspanins constitute a well-conserved superfamily of four-span small membrane proteins (TM4SF), with >30 members in humans, with important roles in numerous mechanisms of cell biology. Moreover, tetraspanins associate with either specific partner proteins or another tetraspanin, generating a network of interactions involved in cell and membrane compartmentalization and having a role in cellular development, proliferation, activation, motility, and membrane fusions. Therefore, tetraspanins are considered regulators of cellular signaling and are often depicted as 'molecular facilitators'.

Haspin: a promising target for the design of inhibitors as potent anticancer drugs.

Protein kinases constitute a large group of enzymes in eukaryotes and have an important role in many cellular processes. Several of these proteins are active kinases, such as haploid germ cell-specific nuclear protein kinase (Haspin), an atypical eukaryotic protein kinase that lacks sequence similarity with other eukaryotic protein kinases. Haspin is a serine/threonine kinase that associates with chromosome and phosphorylates threonine 3 of histone 3 during mitosis.

Synthesis and evaluation of disubstituted N1- and N3-imidazolidin-2-ones acting as potential immunosuppressive agents.

New N1-mono and N1, N2-disubstituted imidazolidin-2-one with a significant immunosuppressive activity have been discovered. Among the 17 synthesized and tested compounds, five of them showed maximal inhibition of proliferation of concanavallin A (Con A)- stimulated splenocytes at 90 microM, identical to that obtained with cyclosporin A (CsA) at 5 microM, an optimal concentration.

Synthesis and antileishmanial activity of new imidazolidin-2-one derivatives.

N(3)-acyl, arylsulfonyl and benzyl derivatives of N(1)-(4,6-dimethylpyridin-2-yl), (5-methylthiazol-2-yl) or (3-methylisoxazol-5-yl)imidazolidin-2-ones were synthesized and evaluated as potential antileishmanial agents. Determination of their cytotoxic effect was carried out using MRC5 cells. Two compounds, 1-(4,6-dimethylpyridin-2-yl)-3-(napht-2-ylsulfonyl)imidazolidin-2-one, 18, and 1-(3-methylisoxazol-5-yl)-3-(4-bromobenzyl)imidazo-lidin-2-one, 25, exerted significant antileishmanial activity in promastigotes of Leishmania (L) mexicana and Leishmania infantum, with IC(50) in the range of 8-16 micro mol L(-1).