6 research outputs found
Pyridin-2-one Synthesis Using Ester Enolates and Aryl Aminoaldehydes and Ketones
An
aldol-like cycloÂcondensation has been used to prepare
heterocyclic-fused pyridin-2-ones from aminoÂaldehydes and ketones
upon treatment with a lithium enolate of ethyl acetate or α-substituted
acetates. These motifs are present in a large number of biologically
active natural products and synthetic compounds and can be accessed
using mild reaction conditions using readily available starting materials.
This methodology allows access to pyrimidinoÂpyridin-2-ones,
pyrazoloÂpyridin-2-ones, and pyridoÂpyridazine diones with
varying substitution patterns
Photoinduced, Copper-Catalyzed Decarboxylative C–N Coupling to Generate Protected Amines: An Alternative to the Curtius Rearrangement
The Curtius rearrangement
is a classic, powerful method for converting
carboxylic acids into protected amines, but its widespread use is
impeded by safety issues (the need to handle azides). We have developed
an alternative to the Curtius rearrangement that employs a copper
catalyst in combination with blue-LED irradiation to achieve the decarboxylative
coupling of aliphatic carboxylic acid derivatives (specifically, readily
available <i>N</i>-hydroxyphthalimide esters) to afford
protected amines under mild conditions. This C–N bond-forming
process is compatible with a wide array of functional groups, including
an alcohol, aldehyde, epoxide, indole, nitroalkane, and sulfide. Control
reactions and mechanistic studies are consistent with the hypothesis
that copper species are engaged in both the photochemistry and the
key bond-forming step, which occurs through out-of-cage coupling of
an alkyl radical
A “Click Chemistry Platform” for the Rapid Synthesis of Bispecific Molecules for Inducing Protein Degradation
Proteolysis
targeting chimeras (PROTACs) are bispecific molecules containing a
target protein binder and an ubiquitin ligase binder connected by
a linker. By recruiting an ubiquitin ligase to a target protein, PROTACs
promote ubiquitination and proteasomal degradation of the target protein.
The generation of effective PROTACs depends on the nature of the protein/ligase
ligand pair, linkage site, linker length, and linker composition,
all of which have been difficult to address in a systematic way. Herein,
we describe a “click chemistry” approach for the synthesis
of PROTACs. We demonstrate the utility of this approach with the bromodomain
and extraterminal domain-4 (BRD4) ligand JQ-1 (<b>3</b>) and
ligase binders targeting cereblon (CRBN) and Von Hippel–Lindau
(VHL) proteins. An AlphaScreen proximity assay was used to determine
the ability of PROTACs to form the ternary ligase–PROTAC–target
protein complex and a MSD assay to measure cellular degradation of
the target protein promoted by PROTACs
A “Click Chemistry Platform” for the Rapid Synthesis of Bispecific Molecules for Inducing Protein Degradation
Proteolysis
targeting chimeras (PROTACs) are bispecific molecules containing a
target protein binder and an ubiquitin ligase binder connected by
a linker. By recruiting an ubiquitin ligase to a target protein, PROTACs
promote ubiquitination and proteasomal degradation of the target protein.
The generation of effective PROTACs depends on the nature of the protein/ligase
ligand pair, linkage site, linker length, and linker composition,
all of which have been difficult to address in a systematic way. Herein,
we describe a “click chemistry” approach for the synthesis
of PROTACs. We demonstrate the utility of this approach with the bromodomain
and extraterminal domain-4 (BRD4) ligand JQ-1 (<b>3</b>) and
ligase binders targeting cereblon (CRBN) and Von Hippel–Lindau
(VHL) proteins. An AlphaScreen proximity assay was used to determine
the ability of PROTACs to form the ternary ligase–PROTAC–target
protein complex and a MSD assay to measure cellular degradation of
the target protein promoted by PROTACs
Oxopyrido[2,3‑<i>d</i>]pyrimidines as Covalent L858R/T790M Mutant Selective Epidermal Growth Factor Receptor (EGFR) Inhibitors
In nonsmall cell lung cancer (NSCLC),
the threonine<sup>790</sup>–methionine<sup>790</sup> (T790M)
point mutation of EGFR kinase
is one of the leading causes of acquired resistance to the first generation
tyrosine kinase inhibitors (TKIs), such as gefitinib and erlotinib.
Herein, we describe the optimization of a series of 7-oxopyridoÂ[2,3-<i>d</i>]Âpyrimidinyl-derived irreversible inhibitors of EGFR kinase.
This led to the discovery of compound <b>24</b> which potently
inhibits gefitinib-resistant EGFR<sup>L858R,T790M</sup> with 100-fold
selectivity over wild-type EGFR. Compound <b>24</b> displays
strong antiproliferative activity against the H1975 nonsmall cell
lung cancer cell line, the first line mutant HCC827 cell line, and
promising antitumor activity in an EGFR<sup>L858R,T790M</sup> driven
H1975 xenograft model sparing the side effects associated with the
inhibition of wild-type EGFR
Discovery and Optimization of Quinazolinone-pyrrolopyrrolones as Potent and Orally Bioavailable Pan-Pim Kinase Inhibitors
The
high expression of proviral insertion site of Moloney murine leukemia
virus kinases (Pim-1, -2, and -3) in cancers, particularly the hematopoietic
malignancies, is believed to play a role in promoting cell survival
and proliferation while suppressing apoptosis. The three isoforms
of Pim protein appear largely redundant in their oncogenic functions.
Thus, a pan-Pim kinase inhibitor is highly desirable. However, cell
active pan-Pim inhibitors have proven difficult to develop because
Pim-2 has a low <i>K</i><sub>m</sub> for ATP and therefore
requires a very potent inhibitor to effectively block the kinase activity
at cellular ATP concentrations. Herein, we report a series of quinazolinone-pyrrolopyrrolones
as potent and selective pan-Pim inhibitors. In particular, compound <b>17</b> is orally efficacious in a mouse xenograft model (KMS-12
BM) of multiple myeloma, with 93% tumor growth inhibition at 50 mg/kg
QD upon oral dosing