STRUCTURE DETERMINATION BY DEUTERIUM LABELING OF A SULFUR-BOUND PETROPORPHYRIN

Structural characterization (MS, NMR) of the major porphyrin 4(D)relea sed by desulfurization of the total organic extract of Gibellina marl (Upper Miocene, Sicily) with deuterated nickel boride disclosed the ma in position of attachment of this porphyrin to the macromolecular netw ork. Chlorophyll metabolites from diatoms bearing a 7 + 5 membered rin g system are likely biological precursors which could be selectively i ncorporated via a C-17''' ketone and preserved in the macromolecular f ractions of this S-rich sediment.