Fig. 1

a DIBOA and D-DIBOA chemical structures. b D-DIBOA synthesis. The chemical synthesis of D-DIBOA was simplified into two steps; the first step is a nucleophilic substitution to introduce an ethyl bromoacetate chain using 2-nitrophenol as the starting material. The product of this reaction is ethyl 2-(2′-nitrophenoxy)acetate (precursor). The second step can be carried out in two ways; the chemical synthesis, which involves a heterogeneous catalysis with a Pd/C catalyst or a reaction catalysed by NfsB enzyme (dashed box), in which two NAD(P)H molecules are oxidized. The regeneration of these cofactors (*) is a limiting factor of the process