A high-field proton magnetic resonance and nuclear Overhauser effect study of prostaglandin E2

Abstract

The proton magnetic resonance (1H nmr) spectrum of prostaglandin E2 (PGE2) in CDCl3 at 400 MHz bas been completely analyzed utilizing homonuclear double resonance, inversion recovery, and nOe difference experiments. The nOe difference experiments are used to assign points of configuration, namely the H-10β and the H-10α proton resonances. A spectral analysis shows that the two protons at C-3 and the two protons at C-4 are nonequivalent, indicating a hindered rotation of the chain. This is possibly due to the hairpin conformation of PGE2 in solution.