Formation of Pyrrolic Compounds by Ultra-violet Irradiation of δ-Aminolevulinic Acid

Abstract

STUDY of the abiogenic formation of biologically important compounds under primitive Earth conditions has led us to suggest the probable path of synthesis of porphine-like ${\text{substances}}^{{\text{1}}_{\text{a}–\text{d}}}$. This hypothesis proposes that porphines and porphine-like substances were formed spontaneously by condensation of pyrroles and aldehydes. A similar scheme has also been suggested by Krasnovskii². The aldehyde, one of the required starting materials for this spontaneous synthesis, has been found as a product of the exposure of Urey's atmosphere to electrical ${\text{discharges}}^{{\text{3}}_{\text{a,b}}}$. The other primitive reactant, pyrrole, was assumed to be present, since acetylene and ammonia under primitive Earth conditions would form pyrroles by the action of electrical discharges⁴.