PETROPORPHYRINS .1. PRELIMINARY CHARACTERIZATION OF THE PORPHYRINS OF GILSONITE

Eight predominantly single carbon number porphyrin fractions were isolated chromatographically from a bitumen, gilsonite (Eocene, Uinta Basin, Utah). Each alkyl porphyrin fraction was analyzed by lH NMR, mass spectrometry, and LC. The seven etioporphyrins isolated ranged from C29 to C32 and contained only methyl, ethyl, and hydrogen substituents, but no meso (bridge) alkyl groups. One of the two C29 etioporphyrin fractions was unambiguously assigned as 2-ethyI-3, 7, 8, 12, 13, 17, 18-heptamethylporphine. The presence of an isocyclic ring was confirmed in the C31 DPEP porphyrin fraction. One of the two C32 DPEP porphyrins isolated cochromatographed on LC with standard deoxophylloerythroetioporphyrin. The combined spcctrometric and chromatographic data indicate that the porphyrins are derived from chlorophylla. © 1979, American Chemical Society. All rights reserved.