Structural features of PGBX (a prostaglandin polymer) deduced by analogies with dimers derived from 15-keto-prostaglandin B.

The polymeric prostaglandin, PGBX, has a beneficial effect on oxidative phosphorylation of damaged mitochondria in vitro and has manifested interesting effects in vivo. Its chemical structure has been partially elucidated by comparison of its 13C-NMR (nuclear magnetic resonance) spectrum with the spectra of prostaglandin monomers. Reported here is subsequent comparison of PGBX with two prostaglandin dimers derived from 15-keto-PGB1, which provide more complete structural information. The two prostaglandin dimers were synthesized and analyzed by 13C-MNR and by other techniques, with particular attention to positions of linkages between the two monomeric prostaglandin subunits of the dimers. Based on these data, some proposals are presented regarding probable locations of linkages between prostaglandin monomeric subunits in the polymeric PGBX.