Nearly all molecules in the universe inherently have a “handedness” property known as chirality due to their 3-Dimensional structure. Two molecules with identical chemical compositions can be “L-” and “D-” mirror images of each other, which behave differently in a living system. The exclusive synthesis and use of L-amino acids by cellular machinery is a ubiquitous biological feature of nearly all organisms. This indicates that homochiral L-amino acids may have existed before the appearance of life. Understanding how this homochirality originated is a key component of any theory regarding the origin of life. However, this is a non-trivial problem. In the absence of a chiral catalyst to promote the formation of a specific mirror image, most chemical reactions generate an equal mix of the two enantiomers. Peptides produced from such racemic solutions would be prohibitively unlikely to afford the required homochiral peptides. It has at times been suggested that this step, the generation of homochirality, is an insurmountable problem. However, a number of chemical processes have been identified that can generate non-racemic products from achiral reactants. The Soai reaction is particularly notable because of its ability to produce homochirality intrinsically, via asymmetric autocatalysis. It produces an enantiomeric excess from achiral starting materials, and thus can be utilized to generate chirality. The Soai reaction itself could not plausibly happen on a primordial earth, and its product is not an amino acid, but it is an example of a chemical reaction which could have led to the homochirality required by life. Toward that end, my research has focused on the conversion of the Soai product into homochiral polypeptides of the L-amino acid valine.

Progress toward the absolute asymmetric synthesis of homochiral peptides

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.