5 research outputs found
Inhibition of MDMX-p53 peptide binding by compound 1 (IC<sub>50</sub> = 3 µM), compound 2 (IC<sub>50</sub>>100 uM).
<p>Inhibition of MDMX-p53 peptide binding by compound 1 (IC<sub>50</sub> = 3 µM), compound 2 (IC<sub>50</sub>>100 uM).</p
Formation of covalent adducts between compound 1 and MDMX.
<p><b>Panel a.</b> Mass spectrum arising from unmodified hMDMX (GST-tagged screening construct) showing unmodified mass of the protein. <b>Panel b.</b> Mass spectrum arising from treatment of 20 µM GST-hMDMX with 100 µM of compound <b>1</b> demonstrating multiple alkylation events. Note that 100 µM is well above the solubility limit of compound <b>1</b> and significant aggregation of compound exists. <b>Panel c.</b> Mass spectrum arising from treatment of 1 µM GST-hMDMX with 5 µM of compound <b>1</b> demonstrating no alkylation events. <b>Panel d.</b> Mass spectrum arising from unmodified hMDMX (untagged aa 23 to 111 construct) showing unmodified mass of the protein. <b>Panel e.</b> Mass spectrum arising from treatment of 20 µM hMDMX with 100 µM of compound <b>1</b> demonstrating partial alkylation. <b>Panel f.</b> Mass spectrum arising from treatment of 1 µM hMDMX with 5 µM of compound <b>1</b> demonstrating no alkylation.</p
Thermal stability equilibria of MDMX.
<p><b>Panel a.</b> Thermal shift data for MDMX (23–111) showing a 7 degree stabilization of the protein’s melting point by addition of compound <b>1</b>. The panel shows individual data sampling points from 3 independent experiments from each condition. <b>Panel b.</b> Dose dependency and time dependency of the effect showing an apparent EC<sub>50</sub> of roughly 1 µM and minimal time dependency. <b>Panel c.</b> Dose dependent reversal of the effects of compound <b>1</b> by TCEP. <b>Panel d.</b> Dose dependent reversal of the effects of compound <b>1</b> by DTT.</p
UPLC-MS-ELSD-PDA as a Powerful Dereplication Tool to Facilitate Compound Identification from Small-Molecule Natural Product Libraries
The generation of natural product
libraries containing column fractions,
each with only a few small molecules, using a high-throughput, automated
fractionation system, has made it possible to implement an improved
dereplication strategy for selection and prioritization of leads in
a natural product discovery program. Analysis of databased UPLC-MS-ELSD-PDA
information of three leads from a biological screen employing the
ependymoma cell line EphB2-EPD generated details on the possible structures
of active compounds present. The procedure allows the rapid identification
of known compounds and guides the isolation of unknown compounds of
interest. Three previously known flavanone-type compounds, homoeriodictyol
(<b>1</b>), hesperetin (<b>2</b>), and sterubin (<b>3</b>), were identified in a selected fraction derived from the
leaves of <i>Eriodictyon angustifolium</i>. The lignan compound
deoxypodophyllotoxin (<b>8</b>) was confirmed to be an active
constituent in two lead fractions derived from the bark and leaves
of <i>Thuja occidentalis</i>. In addition, two new but inactive
labdane-type diterpenoids with an uncommon triol side chain were also
identified as coexisting with deoxypodophyllotoxin in a lead fraction
from the bark of <i>T. occidentalis.</i> Both diterpenoids
were isolated in acetylated form, and their structures were determined
as 14<i>S</i>,15-diacetoxy-13<i>R</i>-hydroxylabd-8Â(17)-en-19-oic
acid (<b>9</b>) and 14<i>R</i>,15-diacetoxy-13<i>S</i>-hydroxylabd-8Â(17)-en-19-oic acid (<b>10</b>), respectively,
by spectroscopic data interpretation and X-ray crystallography. This
work demonstrates that a UPLC-MS-ELSD-PDA database produced during
fractionation may be used as a powerful dereplication tool to facilitate
compound identification from chromatographically tractable small-molecule
natural product libraries
MOESM1 of Diversity-oriented natural product platform identifies plant constituents targeting Plasmodium falciparum
Additional file 1. Specified UPLC conditions, resulting chromatograms and analytical data including NMR, UV and MS spectra for the purified natural products