Nitrosyl iron complex with thiosulfate ligands: reaction with glutathione

• Published in: Russian chemical bulletin Vol. 73; no. 4; pp. 957 - 964
• Main Authors: Novikova, V. O., Emel’yanova, N. S., Pokidova, O. V., Sanina, N. A.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-04-2024; Springer Nature B.V
• Subjects: Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Full Articles; Glutathione; Inorganic Chemistry; Iron; Ligands; Organic Chemistry; Quantum chemistry; Reaction products; Thiosulfates; nitrosyl iron complexes; nitric oxide; reduced glutathione; quantum chemical modeling; UV spectroscopy; Griess test
• ISSN: 1066-5285; 1573-9171
• DOI: 10.1007/s11172-024-4208-8

The reaction between binuclear nitrosyl iron complex (NIC) with thiosulfate ligands Na
2
[Fe
2
(S
2
O
3
)
2
(NO)
4
]•4H
2
O
(1)
and reduced glutathione (GSH) was studied. Using experimental and theoretical methods including UV spectroscopy, Griess test, and quantum chemical modeling, it was shown that the thiosulfate ligands in complex
1
are replaced by GS
−
to give a new binuclear nitrosyl iron complex bearing two glutathione ligands. The mechanism proposed to describe this reaction involves the addition of two glutathione molecules to complex
1
followed by consecutive detachment of thiosulfate ligands without formation of mononuclear NICs. The reaction product exhibits prolonged NO generation. The rate of NO release from the reaction product is two orders of magnitude lower than from complex
1
, namely,
k
eff
= (1.8±0.1)•10
−3
s
−1
and
k
eff
= (2.9±0.9)•10
−5
s
−1
for the reaction in the absence and in the presence of GSH, respectively. The involvement of GSH in the metabolism of complex
1
treated as a promising drug can significantly influence its NO-donor properties.