Systems Chemistry: Kinetic and Computational Analysis of a Nearly Exponential Organic Replicator

Abstract

In 1997, Wang and Sutherland reported a case of selfreplication in a Diels-Alder reaction.[1] This system is remarkable for at least two reasons: it constituted the first example of nearly exponential growth and it had the potential to exhibit two kinds of self-replication, homochiral autocatalysis and heterochiral cross-catalysis, because a chiral diene was employed. Unfortunately, the authors could not complete a stereochemical analysis of their system. We report herein mechanistic and stereochemical studies of variants of the Wang-Sutherland replicator. We show that only one of four potential diastereomers is formed within our detection limits and that this diastereomer is involved in both autocatalytic and cross-catalytic channels. A computational study suggests that the system can be classified as an example of a nearby

Design and Implementation of a Highly Selective Minimal Self‐Replicating System

“…This approach to predetermined dynamic behavior has been termed "systems chemistry" by von Kiedrowski and co-workers. [5] Ultimately, we wish to exploit replicating systems in the construction, selection, [6] and amplification [7] of large molecular and supramolecular assemblies.…”

“…[5]) by von Kiedrowski and co-workers in an almost exponentially replicating system based on the DielsAlder reaction. [19] Raising the temperature will diminish the K a value for the product duplex by increasing the magnitude of the TDS term in the free energy of binding.…”

“…Despite concerted efforts, there are relatively few reports of synthetic self-replicating systems. [5,11] In the context of our long-term goals, we must demonstrate that it is possible to exploit replication to amplify a single structure from a mixture based on its ability to guide its own formation through recognition processes, even when inherently unselective chemical reactions are used to covalently link the building blocks together. The reaction between an N-aryl nitrone and a maleimide is suitable for incorporation in a modular self-replicating system.…”

Systems Chemistry on Ribozyme Self‐Construction: Evidence for Anabolic Autocatalysis in a Recombination Network

“…[19] We report herein on a case of anabolic autocatalysis within a reaction network that assembles a functional ribozyme from smaller oligonucleotide precursors.…”

Light‐Induced Peptide Replication Controls Logic Operations in Small Networks

“…Thus, a common intuitive method was used by changing the concentrations of network constituents, either reactants or templates, in order to enhance specific pathways. [16,18] Changing the characteristics of the principle template-assisted reaction by introducing structural changes to the templates backbone has been utilized in several cases to control small networks, [15,17,[24][25][26] while changes in the environmental conditions by varying, for example, salt concentrations and/or pH, were used to rewire the networks. [14,27] The ability to test and control the response of non-enzymatic networks to external signals might increase their utility and applicability significantly.…”