Incorporation of anthranilate-d4 into DIMBOA in maize

Article abstract of DOI:10.1016/S0040-4039(00)76876-6

2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA) is synthesized in maize from anthranilic acid-d₄ with high retention of deuterium. Retention of deuterium is only consistent with a mechanism of oxidative decarboxylation of o-carboxyanilinoribulose-5-phosphate or other anthranilate derivative via an intermediate in which oxygenation occurs at the carboxyl-bearing ortho carbon before decarboxylation