A concise synthesis of Ni-didecarboxysirohydrochlorin hexamethylester—a model compound for key intermediates in heme d1 and heme biosynthesis

An efficient synthesis of Ni-didecarboxysirohydrochlorin hexamethylester rac-13 was achieved by Barton olefination starting from a readily available dioxo-isobacteriochlorin rac-9. The synthetic route should open a general facile access to this type of naturally occurring hydroporphyrins. Isobacteriochlorins 3–6 are key intermediates in heme d1 and heme biosynthesis of sulfate reducing and denitrifying bacteria as well as in archaebacteria.