A family of previously reported ring-closing metathesis (RCM)-derived macrocycles that exhibit potent Grb2 SH2 domain-binding affinity is characterized by stereoselectively-introduced upper ring junctions that bear bicyclic aryl substituents. However, the synthetic complexity of these macrocycles presents a potential limit to their therapeutic application. Therefore, the current study was under...

Room temperature iodocyclisation of homoallylamines stereoselectively delivers functionalised 2-(iodomethyl)azetidine derivatives in high yield. Increasing reaction temperature from 20 °C to 50 °C switches the reaction outcome to realise the stereoselective formation of functionalised 3-iodopyrrolidine derivatives. It was shown that these pyrrolidines are formed via thermal isomerisation of the...

BACKGROUND There is conflicting evidence concerning the extent to which the intravenous general anesthetic thiopental acts by enhancing inhibitory gamma-aminobutyric acid-mediated (GABAergic) synaptic transmission or by inhibiting excitatory glutamatergic transmission. Yet there are remarkably few studies on the effects of thiopental on functional synapses. In addition, the degree of stereosele...

Development of artificial ribozymes by in vitro selection has so far, mostly been addressed from the viewpoint of fundamental research. However, such ribozymes also have high potential as selective catalysts in practical syntheses. Immobilization of an active and selective ribozyme is an important step towards this end. A 49-nucleotide RNA molecule that was previously found to stereoselectively...

We developed a new method for stereoselective construction of an all-carbon quaternary stereogenic center on a carbocyclic ring based on regio- and stereoselective S(N)2' alkylation reactions of γ,δ-epoxy-α,β-unsaturated cyclic ketones. Treatment of the ketones, which were readily prepared in enantiomerically pure form by means of aldol condensations between 3-ethoxy-2-cycloalkenones and α,β-ep...

Abstract An asymmetric approach toward the synthesis of marine natural product aspergillide‐C has been developed. The convergent uses two Noyori transfer hydrogenations to enantioselectively prepare key fragments, a C ‐1 ‐7 pyranone fragment and ‐8 ‐14 β ‐keto‐sulfone fragment. absolute stereochemistry was established by reduction ‐furylketoester form furyl alcohol. Achmatowicz rearrangement us...

A sequential-type as well a tandem-type chemoenzymatic flow cascade combining an organocatalytic aldol reaction and biocatalytic reduction to form stereoselectively 1,3-diol with two stereogenic centers were developed. Initially, comprehensive screening of 24 alcohol dehydrogenases was carried out the identified candidates applied in different multi-step cascades. All four stereoisomers desired...

Chromatographic separation of black tea polyphenols is too difficult to supply sufficient quantities of pure compounds for biological experiments. Thus, facile methods to prepare black tea constituents were desired. Treatment of epigallocatechin gallate with copper(II) chloride efficiently afforded an unstable quinone dimer, dehydrotheasinensin A, and subsequent treatment with ascorbic acid ste...