Stapling rigidifies peptides through covalent linkages between amino acids. We introduce 2-chloromethyl-6-cyanopyridine for non-symmetric stapling of N-terminal and internal cysteines. This biocompatible method produces diverse peptide macrocycles with enhanced affinity, stability and inhibitory potency.
View Article and Find Full Text PDFThe hypercoordinate [SiH] anion is not stable in solution. Here, we report the room temperature, solution stable molecular [SiH] complex, [{KCa(NON)(OEt)}][SiH] (NON=4,5-bis(2,6-diisopropylanilido)-2,7-di-tert-butyl-9,9-dimethyl-xanthene)), where the [SiH] anion is stabilised within a supramolecular assembly that mimics the solid-state environment of the anion in the lattice of KSiH. Solution-state reactivity of the complex towards carbon monoxide, benzaldehyde, azobenzene and acetonitrile is reported, yielding a range of reduction and C-C coupled products.
View Article and Find Full Text PDFA green carbon capture and conversion technology offering scalability and economic viability for mitigating CO emissions is reported. The technology uses suspensions of gallium liquid metal to reduce CO into carbonaceous solid products and O at near room temperature. The nonpolar nature of the liquid gallium interface allows the solid products to instantaneously exfoliate, hence keeping active sites accessible.
View Article and Find Full Text PDFRoom-temperature synthesis of 2D graphitic materials (2D-GMs) remains an elusive aim, especially with electrochemical means. Here, it is shown that liquid metals render this possible as they offer catalytic activity and an ultrasmooth templating interface that promotes Frank-van der Merwe regime growth, while allowing facile exfoliation due to the absence of interfacial forces as a nonpolar liquid. The 2D-GMs are formed at low onset potential and can be in situ doped depending on the choice of organic precursors and the electrochemical set-up.
View Article and Find Full Text PDFNat Prod Commun
September 2015
The leaf essential oils of the two chemotypes of Eugenia reinwardtiana (Blume) DC growing in Australia have been investigated. Chemotype 1, isolated in 0.2% yield, w/w, dry weight, contained major amounts of α-pinene (10-26%), limonene (1-15%), β-caryophyllene (0.
View Article and Find Full Text PDFThe alkane σ-complex (HEB)W(CO)(2)(pentane) (HEB = η(6)-hexaethylbenzene) is produced from the UV photolysis of (HEB)W(CO)(3) in alkane solvents at low temperature. IR and (1)H and (13)C NMR spectroscopic data are reported, representing the first NMR data for a group 6 alkane complex. Only binding of the methyl functionality of the pentane ligand was observed in (HEB)W(CO)(2)(pentane).
View Article and Find Full Text PDFAlkane complexes of the type Cp'Re(CO)2(alkane) (Cp' = cyclopentadienyl or (isopropyl)cyclopentadienyl; alkane = isotopomers of n-pentane and cyclopentane) have been characterized using NMR spectroscopy following photolysis of Cp'Re(CO)3 in the appropriate alkane at 163-193 K. In the case of n-pentane, three different complexes are observed corresponding to binding of the three different types of carbon in this alkane. ROESY NMR experiments indicate that these isomeric complexes are slowly interconverting intramolecularly at 173 K.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2005
Photolysis of Re(iPrCp)(CO)2(PF3) in liquid or supercritical Xe yields two new compounds [Re(iPrCp)(CO)2Xe and Re(iPrCp)(CO)(PF3)Xe]. Re(iPrCp)(CO)(PF3)Xe has been characterized by NMR and IR spectroscopies. The compound is an organometallic Xe complex that has been characterized by using NMR spectroscopy and is shown to be longer-lived than other organometallic Xe complexes by IR spectroscopy.
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