Biomedical subjects

Steffi Körner

Publications and source records attributed to Steffi Körner.

3 recordsLinked to original sources

PubMed2002

Chemical amplification with encapsulated reagents.

Autocatalysis and chemical amplification are characteristic properties of living systems, and they give rise to behaviors such as increased sensitivity, responsiveness, and self-replication. Here we report a synthetic system in which a unique form of compartmentalization leads to nonlinear, autocatalytic behavior. The compartment is a reversibly formed capsule in which a reagent is sequestered. Reaction products displace the reagent from the capsule into solution and the reaction rate is accelerated. The resulting self-regulation is sensitive to the highly selective molecular recognition properties of the capsule.

Journal Article↗

PubMed2002

Amplification by compartmentalization.

Autocatalysis and chemical amplification are properties of living systems that can lead to increased responsiveness and to self-replication. Here we describe a synthetic system in which a unique form of reagent compartmentalization gives rise to nonlinear kinetics that are subject to the precise size- and shape-selectivity of the host. The reactivity is reminiscent of autocatalytic behaviour, in which there is no direct contact between reagents and products, and our approach offers a general way to impose complex chemical behaviour onto synthetic systems.

Journal Article↗

PubMed1999

C-3'-Branched Thymidines as Precursors for the Selective Generation of C-3'-Nucleoside Radicals.

C-3'-nucleoside radicals can be generated via Norrish type I photocleavage of C-3'-acyl nucleoside derivatives. In monomer experiments employing C-3'-acylthymidine derivatives 2 and 3, a 1:1 mixture of isomers of the H-abstraction products was obtained when the photolysis was carried out in the presence of a hydrogen donor. Derivatives 2 were synthesized by an approach which involves the formation of a silyl-protected cyanohydrin, which is subsequently alkylated with organolithium reagents, followed by hydrolysis. Derivatives 3 could be obtained via a multistep synthesis starting from diol 7. Several different methods were attempted to oxidize the unprotected diol to the alpha-hydroxy aldehyde. Finally, a route was chosen which involves a protection-deprotection sequence followed by oxidation of the free primary alcohol. The resulting modified nucleosides should facilitate the study of C-3'-DNA radicals.

Journal Article↗