Biomimetic Synthesis of a Paracoccus denitrificans Siderophore Analogue

Article abstract of DOI:10.1021/jo00331a026

A biomimetic approach to the synthesis of N⁴-acylated N¹,N⁸-bis(2,3-dihydroxybenzoyl)spermidine siderophores is described.The key to the sequence is the use of Cu(II) as a transitory protecting group for the catechols of N¹,N⁸-bis(2,3-dihydroxybenzoyl)spermidine in the condensation of this synthon with the model acylating agent N-(2-hydroxybenzoyl)glycine.An alternative route to this siderophore analogue employing classical methods is offered as proof of structure.Preliminary investigations aimed at characterizing the chelate of interest are also described.Proton NMR paramagnetic line broadening studies confirm the catechols of N¹,N⁸-bis(2,3-dihydroxybenzoyl)spermidine to be the chelating functionality.The stoichiometry of the complex is determined by spectrophotometric methods while the cumulative formation constants of the various protonated species are established by potentiometric techniques.