This research is centered around the preparation of possible geochemical intermediates which can be used to model the formation of unusual petroporphyrin structures found in organic sediments. Compounds including cycloalkanoporphyrins, deoxophylloerythroetioporphyrin, meso,beta-ethanoporphyrins, petroporphyrins with fused exocyclic rings and novel porphyrin dimers are among the proposed synthetic targets. %%% With this RUI award, the Synthetic Organic Program is supporting the research of Dr. Timothy D. Lash of the Department of Chemistry at Illinois State University. Professor Lash will focus his research on the synthesis of porphyrin molecular fossils. The work will give a better understanding of the origins of organic sediments and will involve undergraduates in an exciting area of research.