11 research outputs found
The subgenomic promoter of brome mosaic virus folds into a stem-loop structure capped by a pseudo-triloop that is structurally similar to the triloop of the genomic promoter
Supramolecular & Biomaterials Chemistr
Structure and photophysical properties of a series of new 1D d 10 Coinage Metal Organic Chalcogenolates (MOCs): [M(o-SPhCO2H)]n (M = Cu, Ag, Au)
SSCI-VIDE+CDFA+OVE:ADMInternational audienceThiosalicylic acid is hard-soft donor ligand, able to coordinate numerous metals [1]. A significant number of coordination compounds of d10 metals have been reported. However, crystallographic studies of polymeric species stayed very limited compared to their mono- and oligomeric counterparts. For example, preparation of polymeric [Au(oSCPhCO2H)]n has been reported [2], as well as polymeric compounds of silver thiosalicylate [3], but no crystallographic structure was reported. A number of Cu(II) thiosalicylates [4], a mixed-valence Cu(I)2Cu(II) complex [5] and no Cu(I) complexes have been described up to our knowledge. In most cases structural studies are precluded due to the strong affinity between sulfur and coinage metals, inducing a rapid precipitation of coordination polymers making single crystals hardly obtainable. In presented work, we report extensive pioneering structural study of three polymeric species of Cu(I), Au(I) and Ag(I). Structural study was performed by means of powder X-ray diffraction and PDF (pair distribution function) calculations. These coordination polymers have similar 1D structures. Based on this fact, we are able to discuss the influence of the structure and the nature of the metallic ion on photophysical properties of these materials. They emin in orange to NIR part of the spectrum. High quantum yields make them interesting for illumination and as NIR-emitters. [1] T. Wehr-Candler et al. Coord. Chem. Rev. 2016, 313, 111.[2] R.E. Bachman et al. Z. Naturforsch. 2009, 64B, 1491. [3] K. Nomiya et al. J. Inorg. Biochem. 1995, 58, 255. [4] See for example M.S. Abu-Bakr, Monatsh. Chem. 1997, 128, 563. [5] R.C. Bott et al. Chem. Commun. 1998, 2403
An intrinsic dual-emitting gold thiolate coordination polymer, [Au( plus I)(p-SPhCO2H)](n), for ratiometric temperature sensing
SSCI-VIDE+CDFA+OVE:ADMInternational audienc
Identification and Characterization of Second-Generation Invader Locked Nucleic Acids (LNAs) for Mixed-Sequence Recognition of Double-Stranded DNA
The
development of synthetic agents that recognize double-stranded
DNA (dsDNA) is a long-standing goal that is inspired by the promise
for tools that detect, regulate, and modify genes. Progress has been
made with triplex-forming oligonucleotides, peptide nucleic acids,
and polyamides, but substantial efforts are currently devoted to the
development of alternative strategies that overcome the limitations
observed with the classic approaches. In 2005, we introduced Invader
locked nucleic acids (LNAs), i.e., double-stranded probes that are
activated for mixed-sequence recognition of dsDNA through modification
with “+1 interstrand zippers” of 2′-<i>N</i>-(pyren-1-yl)methyl-2′-amino-α-l-LNA monomers.
Despite promising preliminary results, progress has been slow because
of the synthetic complexity of the building blocks. Here we describe
a study that led to the identification of two simpler classes of Invader
monomers. We compare the thermal denaturation characteristics of double-stranded
probes featuring different interstrand zippers of pyrene-functionalized
monomers based on 2′-amino-α-l-LNA, 2′-<i>N</i>-methyl-2′-amino-DNA, and RNA scaffolds. Insights
from fluorescence spectroscopy, molecular modeling, and NMR spectroscopy
are used to elucidate the structural factors that govern probe activation.
We demonstrate that probes with +1 zippers of 2′-<i>O</i>-(pyren-1-yl)methyl-RNA or 2′-<i>N</i>-methyl-2′-<i>N</i>-(pyren-1-yl)methyl-2′-amino-DNA monomers recognize
DNA hairpins with similar efficiency as original Invader LNAs. Access
to synthetically simple monomers will accelerate the use of Invader-mediated
dsDNA recognition for applications in molecular biology and nucleic
acid diagnostics