Figure 1.

Reductive nitrosylation of metMb (50 μM) by (A) 1 (100 μM), or (B) 2 (100 μM). The assay was performed in phosphate-buffered saline (PBS) (pH 7.4) containing 50 μM DTPA at 37 °C under deaerated conditions until there were no further spectral changes at 543 and 575 nm (1, 2, 4, 6, 9, 14, 23, and 46 min for 1; 3−107 min in 4- to 10-min intervals shown for 2). Concentrations of MbNO produced under these conditions by 1 and 2 were ∼18 and 45 μM, respectively.