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Transformation of Prostaglandin D₂ to 11-Dehydro Thromboxane B₂ by Baeyer-Villiger Oxidation.

ABSTRACT: Prostaglandin D₂ is one of five chief prostanoids formed in the cyclooxygenase pathway of arachidonic acid oxidation. Except for a single oxygen atom, PGD₂ is structurally identical to 11-dehydro thromboxane B₂ (11d-TxB₂ ), a urinary metabolite of the pro-aggregatory platelet activator, thromboxane A₂ . The close structural relationship suggested that one might be transformed to the other. Accordingly, we tested whether the cyclopentanone of PGD₂ can be expanded to the ?-lactone of 11d-TxB₂ in a Baeyer-Villiger oxidation. Oxidation of PGD₂ with two standard oxidants showed that 11d-TxB₂ was formed only with H₂ O₂ but not with peracetic acid. Byproducts of the H₂ O₂ -mediated oxidation were hydroperoxide derivatives and isomers of PGD₂ . Chemical oxidation of PGD₂ to 11d-TxB₂ may be a model for an equivalent enzymatic transformation, suggesting a possible link in the metabolism of PGD₂ and thromboxane A₂ .

SUBMITTER: Nakashima F

PROVIDER: S-EPMC7153723 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Transformation of Prostaglandin D2 to 11-Dehydro Thromboxane B2 by Baeyer-Villiger Oxidation.

Nakashima Fumie F Schneider Claus C

Lipids 20191212 1

Prostaglandin D2 is one of five chief prostanoids formed in the cyclooxygenase pathway of arachidonic acid oxidation. Except for a single oxygen atom, PGD2 is structurally identical to 11-dehydro thromboxane B2 (11d-TxB2 ), a urinary metabolite of the pro-aggregatory platelet activator, thromboxane A2 . The close structural relationship suggested that one might be transformed to the other. Accordingly, we tested whether the cyclopentanone of ...[more]

PMID: 31833075

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