75073-11-9Relevant articles and documents
Encoding Multiple Reactivity Modes within a Single Synthetic-Replicator
Kosikova, Tamara,Philp, Douglas,Robertson, Craig C.
, p. 11139 - 11152 (2020)
Establishing programmable and self-sustaining replication networks in pools of chemical reagents is a key challenge in systems chemistry. Self-replicating templates are formed from two constituent components with complementary recognition and reactive sites via a slow bimolecular pathway and a fast template-directed pathway. Here, we re-engineer one of the components of a synthetic replicator to encode an additional recognition function, permitting the assembly of a binary complex between the components that mediates replicator formation through a template-independent pathway, which achieves maximum rate acceleration at early time points in the replication process. The complementarity between recognition sites creates a key conformational equilibrium between the catalytically inert product, formed via the template-independent pathway, and the catalytically active replicator that mediates the template-directed pathway. Consequently, the rapid formation of the catalytically inert isomer kick-starts replication through the template-directed pathway. Through kinetic analyses, we demonstrate that the presence of the two recognition-mediated reactivity modes results in enhanced template formation in comparison to that of systems capable of exploiting only a single recognition-mediated pathway. Finally, kinetic simulations reveal that the conformational equilibrium and both the relative and absolute efficiencies of the recognition-mediated pathways affect the extent to which self-replicating systems can benefit from this additional template-independent reactivity mode. These results allow us to formulate the rules that govern the coupling of replication processes to alternative recognition-mediated reactivity modes. The interplay between template-directed and template-independent pathways for replicator formation has significant relevance to ongoing efforts to design programmable and adaptable replicator networks.
HETEROCYCLIC COMPOUND
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Paragraph 0305, (2017/11/18)
Provided is a compound having an antagonistic action on an NMDA receptor containing the NR2B subunit, and is useful as a prophylactic or therapeutic agent for major depression, bipolar disorder, migraine, pain, peripheral symptoms of dementia and the like
Remarkable switch in the regiochemistry of the iodination of anilines by N-iodosuccinimide: Synthesis of 1,2-dichloro-3,4-diiodobenzene
Shen, Hao,Vollhardt, K. Peter C.
supporting information; experimental part, p. 208 - 214 (2012/03/11)
Direct iodination of anilines by NIS in polar solvents (such as DMSO) affords p-iodinated products with up to >99% regioselectivity. Switching to less polar solvents (such as benzene) in the presence of AcOH inverts this outcome toward dramatically increased or preferential generation of the o-isomers, also with up to >99% regioselectivity. This finding was exploited in the synthesis of 1,2-dichloro-3,4-diiodobenzene. Georg Thieme Verlag Stuttgart - New York.