4-(2'-Carboxyphenyl)-4-oxobutyryl coenzyme A ester, an intermediate in vitamin K2 (menaquinone) biosynthesis.

Enzyme preparations from Mycobacterium phlei, Escherichia coli and Galium mollugo cell suspension cultures were incubated in the presence of 4-(2'-carboxyphenyl)-4-oxobutyrate (i.e. o-succinylbenzoic acid, OSB, 1), ATP, coenzyme A and Mg2+.

Enzymic synthesis of o-succinylbenzoyl-CoA in cell-free extracts of anthraquinone producing Galium mollugo L. cell suspension cultures.

o-Succinylbenzoic acid (OSB) is an intermediate in the biosynthesis of shikimatederived anthraquinones. The cell free activation of o-succinylbenzoic acid in extracts of anthraquinone producing cells of Galium mollugo L. is demonstrated for the first time.