Catalysts,
Год журнала:
2022,
Номер
12(8), С. 915 - 915
Опубликована: Авг. 19, 2022
α-Imino
gold
carbenoid
species
have
been
recognized
as
key
intermediates
in
a
plethora
of
processes
involving
gold-activated
alkynes.
Here,
we
explored
the
pathways
Au(I)-catalyzed
[3
+
2]
reaction
between
mild
nucleophiles:
anthranil,
1,2,4-oxadiazole,
or
4,5-dihydro-1,2,4-oxadiazole,
and
an
ynamide,
PhC≡C-N(Ts)Me,
proceeding
via
formation
aforementioned
α-imino
carbene
intermediate
which,
after
intramolecular
capture,
regioselectively
produces
2-amino-3-phenyl-7-acyl
indoles,
N-acyl-5-aminoimidazoles,
N-alkyl-4-aminoimidazoles,
respectively.
In
all
cases,
regioselectivity
substituents
at
2,
3
7-acyl-indole
ring
4,
5
substituted
imidazole
is
decided
first
transition
state,
attack
nitrogen
on
C1
C2
carbon
activated
ynamide.
A
subsequent
steep
energy
drop
furnishes
carbene.
These
features
are
more
pronounced
for
anthranil
4,5-dihydro-1,2,4-oxadiazole
reactions.
Strikingly,
significant
due
to
unstable
carbene,
which
spontaneous
benzaldehyde
elimination
converted
stabilized
one.
Compared
1,2,4-oxadiazoles
4,5-dihydro-1,2,4-oxadiazoles
found
be
significantly
complex
than
anticipated
original
research.
For
instance,
compared
five-member
from
one
competitive
route
involves
consisting
four-member
condensed
with
three-member
ring,
metathesis
expansion
led
ring.
Molecules,
Год журнала:
2024,
Номер
29(14), С. 3366 - 3366
Опубликована: Июль 17, 2024
This
work
describes
the
synthesis,
characterization,
and
in
vitro
silico
evaluation
of
biological
activity
new
functionalized
isoxazole
derivatives.
The
structures
all
compounds
were
analyzed
by
IR
NMR
spectroscopy.
4c
4f
further
confirmed
single
crystal
X-ray
their
compositions
unambiguously
determined
mass
spectrometry
(MS).
antibacterial
effect
isoxazoles
was
assessed
against
Escherichia
coli,
Bacillus
subtilis,
Staphylococcusaureus
bacterial
strains.
Isoxazole
4a
showed
significant
E.
coli
B.
subtilis
compared
to
reference
antibiotic
drugs
while
4d
also
exhibited
some
effects.
molecular
docking
results
indicate
that
synthesized
exhibit
strong
interactions
with
target
proteins.
Specifically,
displayed
a
better
affinity
for
S.
aureus,
comparison
drugs.
dynamics
simulations
performed
on
strongly
support
stability
ligand–receptor
complex
when
interacting
active
sites
proteins
from
subtilis.
Lastly,
Absorption,
Distribution,
Metabolism,
Excretion
Toxicity
Analysis
(ADME-Tox)
reveal
molecules
have
promising
pharmacokinetic
properties,
suggesting
favorable
druglike
properties
potential
therapeutic
agents.
Chemical Communications,
Год журнала:
2022,
Номер
58(28), С. 4476 - 4479
Опубликована: Янв. 1, 2022
A
ruthenium-catalyzed
oxidative
coupling
of
vinylene
carbonate
with
isoxazoles
has
been
developed
to
achieve
the
direct
C-H
formylmethylation
a
diverse
array
arylisoxazoles
utilizing
isoxazole
ring
as
directing
group.
simple
manipulation
established
reaction
conditions
leads
formation
fused-anthranils.
Importantly,
functions
both
formylmethyl
cation
equivalent
through
decarboxylation
process
and
an
acetylene
equivalent.
Control
experiments
were
conducted
elucidate
plausible
mechanism.
This
methodology
is
expected
provide
facile
expeditious
approach
for
synthesis
Organometallics,
Год журнала:
2023,
Номер
42(3), С. 211 - 217
Опубликована: Янв. 3, 2023
Many
methods
report
the
scission
of
N–O
bonds
aromatic
heterocycles
and
their
subsequent
functionalization.
Oxidative
addition
is
one
presumed
pathways
through
which
bond
activation
with
transition
metals
achieved.
We
first
well-defined
pathway
(benz)isoxazole's
oxidative
addition.
also
provide
control
experiments,
show
that
may
be
broken
by
strong
inorganic
reductants.
These
results
highlight
are
susceptible
to
both
reduction
addition,
has
important
implications
for
catalysis.
Exploring
reactivity
these
complexes
toward
a
series
electrophiles
leads
discovery
Staudinger-type
β-lactam
synthesis
upon
reaction
ketene.
Finally,
we
demonstrate
choice
different
metal/ligand
combinations
allows
selective
into
either
C–I
or
in
presence
other.
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(27), С. 5567 - 5586
Опубликована: Янв. 1, 2023
Efficacious
protocols
have
been
established
to
synthesize
a
structurally
privileged
Π-extended
coumarin-fused
pyridone
nucleus
by
activating
the
vinylic
C(sp2)-H
bond
of
coumarin-3-carboxamide
under
influence
inexpensive
Ru(II)-metal.
Here
an
N-methoxy
carboxamide
entity
has
exploited
as
chelating
fragment
manifest
functionalization
with
concomitant
(4
+
2)
annulation
reaction,
resulting
in
heterocyclic
ring-forming
along
sulfoxonium
ylide
and
iodonium
representative
bench-stable
carbene
surrogates.
This
diverse
heterocycle
formation
via
insertion
strategies,
is
further
expanded
activate
ortho-C(sp2)-H
bonds
different
heterocycles
employing
sp2-N
moiety
directing
group
develop
acyl-alkylated/alkenylated
quinazolines,
isoxazoles
highly
fluorescent
pyridone-N-oxides.
Intriguingly,
during
evaluation
versatility
current
protocols,
one-pot
double
C-H
activation
rationalized
presence
ylide,
which
results
biologically
potent
benzimidazole-fused
coumarin-centered
bridge-headed
polycyclic
heteroarenes.
Furthermore,
chemo-selective
late-stage
synthetic
transformation
being
designed
differently
substituted
analogues
switching
nature
reducing
agent.
In
addition,
photophysical
experiment
was
done
on
one
pyridine-N-oxide
compound
(7e)
delightfully
it
exhibited
fluorescence
quenching
activity
selectively
Al3+
ions,
appears
be
unique
feature
our
methodology.
Finally,
upon
correlation
merit
developed
pathways,
mediated
strategy
superior.
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(44), С. 8794 - 8812
Опубликована: Янв. 1, 2023
Modern
times
have
witnessed
an
uprise
in
the
synthesis
and
derivatization
of
nitrogen-containing
fused
heterocycles.
Amination
reactions
involving
nitrene
chemistry
always
been
most
convenient
choice
for
incorporation
a
nitrogen
atom
molecule.
The
utilization
open
species
harnesses
harsh
conditions.
Hence,
transition
metal-catalyzed
C-H
amination
using
aminating
agents
attractive
choice.
Electrophilic
are
well
exploited
due
to
their
desirable
reaction
Out
all,
anthranils
paved
way
forward
utility
simultaneously
forming
two
new
functional
groups
(amine
carbonyl).
follows
metal-nitrenoid
pathway.
Often,
has
followed
by
Lewis
acid
or
metal-mediated
intramolecular
cyclization
directly
produce
This
review
broadly
demonstrates
as
agent
reactions.
focus
given
scope,
limitations,
mechanistic
understanding
such
electrophilic
agent,
anthranil,
with
metals.
Chemical Communications,
Год журнала:
2024,
Номер
unknown
Опубликована: Янв. 1, 2024
The
catalytic
asymmetric
electrophilic
functionalization
of
the
less
reactive
N-heteroaromatic
compounds
has
been
reported
using
approach
introduction
an
exocyclic
amino
substituent.
Organic Letters,
Год журнала:
2022,
Номер
24(17), С. 3270 - 3274
Опубликована: Апрель 26, 2022
A
ring-opening
fluorination
of
isoxazoles
has
been
developed.
Upon
treatment
with
an
electrophilic
fluorinating
agent
(Selectfluor),
followed
by
deprotonation
leads
to
tertiary
fluorinated
carbonyl
compounds.
This
method
features
mild
reaction
conditions,
good
functional
group
tolerance,
and
a
simple
experimental
procedure.
Diverse
transformations
the
resulting
α-fluorocyanoketones
were
also
demonstrated,
furnishing
variety
Advanced Synthesis & Catalysis,
Год журнала:
2023,
Номер
365(2), С. 244 - 251
Опубликована: Янв. 6, 2023
Abstract
Herein,
a
catalyst‐free
method
for
synthesizing
4,5‐dihydroisoxazole‐5‐methanols
is
proposed,
whereby
isoxazolines
are
constructed
through
the
NCS‐mediated
1,3‐dipolar
cycloaddition
reaction
of
aldoximes
and
allyl
alcohol
in
presence
K
2
CO
3
at
room
temperature
via
one‐pot
route.
The
was
achieved
water
medium
to
introduce
low‐cost
direct
protocol
isoxazolines.
This
offers
advantages
including
use
an
oxidant‐free
transition
metal‐free
approach,
broad
scope
aldoxime
substrates,
room‐temperature
reaction,
good
higher
yields
(42–92%),
involvement
gram‐scale
synthesis.
magnified
image
Heterocycles,
Год журнала:
2023,
Номер
106(7), С. 1187 - 1187
Опубликована: Янв. 1, 2023
The
three-component
reactions
using
aryl
aldehydes,
hydroxylamine
hydrochloride,
and
β-ketoesters
(ethyl
acetoacetate,
ethyl
4-chloro-3-oxobutanoate,
3-oxohexanoate)
as
available
precursors
were
performed
to
synthesize
arylideneisoxazol-5-ones.The
experiments
have
been
catalyzed
sodium
cyclamate
high
yields
of
products
obtained
under
green
conditions
at
room
temperature.Relatively
shorter
reaction
time,
free
from
the
use
organic
medium,
simplicity
method,
formation
pure
without
chromatographic
methods,
inexpensive
are
among
advantages
this
method.Heating
other
devices
for
energy
supply
not
required.Also,
in
process,
water
a
medium
is
line
with
principles
chemistry.In
world
heterocycles,
isoxazoles
their
special
place,
probably
because
diversity
also
many
applications.
1The
isoxazole
cyclic
system
documented
an
important
moiety
wide
variety
pharmaceutical
drugs.
2
According
literature,
they
ranked
31st
351
ring
systems
found
synthetic
medicinal
compounds.
3
core
naturally
occurring
nature,
agrochemicals,
propellant
plasticizers,
explosives
well
versatile
building
blocks
synthesis.
4The
can
be
observed
liquid
crystalline
compounds
interesting
optoelectronic
properties.
5Among
most
studied
isoxazoles,
isoxazol-5(4H)-ones
privileged
heterocycles
that
range
drugs,
natural
products,
biologically
active
compounds,
great
interest.
6Many
properties
such
antiviral,
anti-inflammatory,
antioxidant,
anticancer,
antimicrobial,
antifungal,
anti-Alzheimer's
disease,
antineoplastic,
anti-tuberculosis
belong
category
arylideneisoxazol-5-ones.
7
Besides,
