Reaction between a haemoglobin model compound and hydrosulphide in aqueous solution.

The reaction between hydrosulphide (SH(-)) and a haemoglobin model compound, composed of a Fe(III)-porphyrin and a cyclodextrin dimer possessing a pyridine-linker (met-hemoCD3), was studied. Met-hemoCD3 formed a stable (SH(-))-met-hemoCD3 complex in oxygen-free neutral aqueous solution. In the presence of O2, reversible ligand exchange between (SH(-))-met-hemoCD3 (Fe(III)) and O2-hemoCD3 (Fe(II)) occurred.