Making molecules make themselves - The chemistry of artificial replicators

Examples of chemical systems capable of templating and catalyzing their own synthesis - so-called replicating systems - have begun to appear in the chemical literature over the last 20 years. For the biologist, these systems represent a link with the origin of life - their study can perhaps shed light on prebiotic chemical evolution. For the synthetic chemist, they represent the ultimate synthetic machine, capable of tem- plating the production of a large number of perfect copies of themselves from a single original molecule. One of the driving forces behind this research area has been the recognition of the important role that replication plays in biology and a desire to answer a fundamental question - "Is the structural complexity of nucleic acids necessary to store and transmit information at a molecular level?" In addition, the concept of a chemical template that is capable of making billions of exact copies of itself, given appropriate starting materials, is a highly attractive one for the burgeoning field of systems chemistry. It is therefore clear that the development of a detailed understanding of the behaviour of replicating systems has important perspectives for both biology and chemistry. In the present review, we will concentrate on the design and implementation of systems based on small, synthetic organic molecules that can reproduce themselves.