A synthetic model of the nonheme iron-superoxo intermediate of cysteine dioxygenase

A nonheme Fe( ii ) complex (1) that models substrate-bound cysteine dioxygenase (CDO) reacts with O 2 at −80 °C to yield a purple intermediate (2). Analysis with spectroscopic and computational methods determined that 2 features a thiolate-ligated Fe( iii ) center bound to a superoxide radical, mimicking the putative structure of a key CDO intermediate. A nonheme Fe( ii ) complex that models substrate-bound cysteine dioxygenase reacts with O 2 at low temperature to yield an iron-superoxo intermediate.