Dehydration of prostaglandins: study by spectroscopic method

Abstract

The ultraviolet (UV) and optical rotatory dispersion (ORD) spectra of prostaglandins E1, A1, B1, and their naturally derived 15-epimers are presented. The dehydration sequence E → A → B under acidic and basic conditions has been studied by UV and ORD. Conditions for quantitative conversion of PGE1 to PGA1 are described.The combination of ORD and UV affords a nondestructive assay which can determine the relative amounts of E-, A-, and B-type prostaglandins with as little as 1-2 μg of material. The total quantity of prostaglandins can be estimated (±15%) in this way or, more accurately, by treatment with alkali of an aliquot (200 ng is sufficient) and determination of the change in absorbance at 278 nm.

Keywords

• prostaglandins
• spectroscopic assay
• UV spectra
• optical rotatory dispersion
• β-hydroxyketones