Pyrazolo[1,5-a]-1,3,5-triazine C-nucleoside as deoxyadenosine analogue: synthesis, pairing, and resistance to hydrolysis.

The synthesis of a pyrazolo[1,5-a]-1,3,5-triazine C-nucleoside (dA(PT)), designed to form two hydrogen bonds with a complementary dT residue, is reported. Oligonucleotides including this dA nucleoside analogue possess base-pairing properties similar to those of the parent oligonucleotide. This dA nucleoside analogue is more resistant to acid-catalyzed hydrolysis than dA.

Novel 5-azaindolocarbazoles as cytotoxic agents and Chk1 inhibitors.

We describe here an efficient synthesis of new 5-azaindolocarbazoles designed for cytotoxic and Chk1 inhibiting properties. The synthesis of 'symmetrical' and 'dissymmetrical' structures is discussed. Concerning the dissymmetrical 5-azaindolocarbazoles derivatives, with both an indole moiety and a 5-azaindole moiety, the synthesis was achieved using two very efficient key steps.

The glucosinolate-myrosinase system. New insights into enzyme-substrate interactions by use of simplified inhibitors.

Myrosinase, a thioglucoside glucohydrolase, is the only enzyme able to hydrolyse glucosinolates, a unique family of molecules bearing an anomeric O-sulfated thiohydroximate function. Non-hydrolysable myrosinase inhibitors have been devised and studied for their biological interaction. Diverse modifications of the O-sulfate moiety did not result in a significant inhibitory effect, whereas replacing the D-glucopyrano residue by its carba-analogue allowed inhibition to take place.