Sulfur ligands groups

In this case, the diminution in Lewis acidity caused by the introduction of the two, less-electronegative, sulfur ligands prevents any reaction with the dithiol enzyme, regardless of the nature of the alkyl group. 

Adds a ligand to one metal center with retention of sulfur coordinated group... 

Reaction of (34) with the bidentate sulfur ligand isotrithionedithiol (H2dmit, (278)) produced a dianionic complex. The reaction of (278) in which the thiol groups were deprotected in situ prior to the substitution reaction with [TcNClJ in acetonitrile gave a 45% yield of [TcN(dmit)2] ... 

The prosthetic groups of iron-sulfur proteins fall into several classes (Lov-enberg, 1977 Spiro 1982). Rubredoxins bind single iron atoms with four cys-teinyl sulfur ligands they function as electron carriers in some bacterial systems. Rubredoxins generally have two such centers per molecule in the ferric state each iron center is EPR detectable. 

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