Synthesis, characterization, and biological evaluation of technetium(III) complexes with tridentate/bidentate S,E,S/P,S coordination (E = O, N(CH(3)), S): a novel approach to robust technetium chelates suitable for linking the metal to biomolecules.

A novel type of mixed-ligand Tc(III) complexes, [Tc(SCH(2)CH(2)-E-CH(2)CH(2)S)(PR(2)S)] (E = S, N(CH(3)); PR(2)S = phosphinothiolate with R = aryl, alkyl) is described. These "3+2"-coordinated complexes can be prepared in a two-step reduction/substitution procedure via the appropriate chloro-containing oxotechnetium(V) complex [TcO(SES)Cl] [E=S, N(CH(3)]. Tc(III) compounds have been fully characterized both in solid and solution states and found to adopt the trigonal-bipyramidal coordination geometry.

A novel technetium-99m radioligand for the 5-HT(1A) receptor derived from desmethyl-WAY-100635 (DWAY).

This paper reports the synthesis, biological evaluation and in vitro autoradiography of a new technetium-99m radioligand with high affinity for the 5-HT(1A) receptor. The neutral complex combines an N(2)S(2) diamine dithiol (DADT) ligand as complexing moiety for oxotechnetium(V) and a 2-(1-piperazino)phenol via a 6-carbon alkyl chain, derived from desmethyl-WAY 100635 (DWAY). The complex displays an IC(50) value for the 5-HT(1A) receptor of 1.