Water-soluble silver(I) complexes of (R)-(+)- and (S)-(-)-2-pyrrolidone-5-carboxylic acid and their antimicrobial activities. Chiral helical polymer and polymer sheet structures in the solid-state formed by self-assembly of dimeric [Ag(Hpyrrld)](2) cores

The synthesis and characterization of two water-soluble silver(I) complexes {[Ag(R-Hpyrrld)](2)}(n) 1 and {[Ag-2(R-Hpyrrld)(S-Hpyrrld)]}(n) 2 [R- and S-H(2)pyrrld=(R)-(+)- and (S)-(-)-2-pyrrolidone-5-carboxylic acid, respecti vely] showing wide ranging effective antimicrobial activity are described a nd their crystal structures determined. Single-crystal X-ray analysis revea ls that 1 and 2 in the solid state are a right-handed chiral helical polyme r and an achiral polymer sheet, respectively, formed by self-assembly of th e Ag-2(carboxylato-O,O')(2) units [Ag-Ag 2.899(2) Angstrom for 1 and 2.875( 2) Angstrom for 2; O-Ag-O 160.3(5), 163.2(5)degrees for 1 and 163.1(2)degre es for 2]. The helicity of 1 in the solid state was accomplished by connect ion of only one oxo group in one dimeric core to one of the silver(I) cente rs of the adjacent dimeric unit. It is elucidated that the chiral helical p olymer 1 is a mirror image of the recently characterized enantiomer {[Ag(S- Hpyrrld)](2)}(n) 3. The bonding modes of 1 and 3 are quite different from t hose of the achiral polymer sheet 2. Complexes 1 and 2 have been also chara cterized by elemental analysis, TG/DTA, FT-IR, and solution (H-1 and C-13) and solid-state C-13 NMR spectroscopies. The wide ranging effective antimic robial activities observed in the complexes suggest that weak silver(I)-oxy gen bonding properties play a key role.