Research Square (Research Square),
Год журнала:
2023,
Номер
unknown
Опубликована: Дек. 13, 2023
Abstract
N-Glycosylated
heterocycles
play
important
roles
in
biological
systems
and
drug
development.
The
synthesis
of
these
compounds
heavily
relies
on
ionic
N-glycosylation,
which
is
usually
constrained
by
factors
like
labile
glycosyl
donors,
precious
metal
catalysts,
stringent
conditions.
Herein,
we
report
an
unprecedented
radical-based
method
for
synthesizing
N
-glycosides
leveraging
copper
metallaphotoredox
catalysis.
Complementing
with
the
well-established
approaches,
our
employs
inexpensive
photo-
copper-
catalysts
can
tolerate
some
extent
water.
Furthermore,
readily
available
stable
1-hydroxycarbohydrates
are
successfully
utilized
first
time
N-glycosylation.
reaction
exhibits
a
broad
substrate
scope,
encompassing
76
examples,
demonstrates
high
stereoselectivity,
favoring
1,2-trans
selectivity
furanoses
α-selectivity
pyranoses.
It
also
site-selectivity
substrates
containing
multiple
N-atoms.
synthetic
utility
was
showcased
through
late-stage
functionalization
bioactive
pharmaceuticals
Olaparib,
Axitinib,
Metaxalone.
Mechanistic
studies
proved
presence
intermediates
importance
Angewandte Chemie,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 6, 2024
Abstract
Most
of
the
reported
work
focus
on
development
O
‐,
N
C
‐
and
S
‐glycosylation
methods.
However,
no
study
explores
P(III)‐glycosylation
reaction.
Herein
we
describe
a
convenient
protocol
to
realize
process.
A
simple
β
‐phosphino
ester
is
adopted
as
P(III)‐transfer
reagent
for
this
new
type
glycosylation
via
nucleophilic
substitution
release
strategy.
Diverse
phosphine
units
are
introduced
anomeric
center
various
sugars
efficiently
with
excellent
stereoselectivity.
The
value
method
showcased
by
prepared
P(III)‐sugars
novel
linkers
in
bioactive
molecule
conjugation,
chiral
ligands
metal‐catalyzed
asymmetric
allylic
substitutions
organocatalysts.
Preliminary
mechanistic
studies
corroborated
designed
Current Organic Synthesis,
Год журнала:
2023,
Номер
21(1), С. 78 - 90
Опубликована: Апрель 18, 2023
Hydrated
strontium
perchlorate
[Sr(ClO4)2.3H2O]
acts
as
a
very
strong
oxidizing
and
dehydrating
agent.
Until
now,
it
could
not
be
reported
catalyst
in
dehydration
mechanism-based
organic
synthetic
reactions.
Therefore,
is
important
to
find
whether
an
effective
for
one-pot
multicomponent
reactions
(MCRs).The
main
objective
of
the
present
work
development
novel
process
synthesis
1,4-dihydropyrimidinones
through
strategy
using
hydrated
Sr(ClO4)2
catalyst.
Furthermore,
includes
optimization,
stereoselectivity,
spectroscopic
characterization
synthesized
compounds.Conventional
microwave-supported
20
mol
%
via
solvent-free
reaction
was
discovered
new
catalytic
MCR
methodology.
The
box-Behnken
design
approach
advanced
analytical
techniques
were
used
optimization
analysis.The
results
confirmed
that
Sr(ClO4)2;
works
efficient
under
both
conventional
microwave
heating.
It
laboratory
stereoselectively
with
moderate
excellent
yield
without
any
undesirable
effect.
Microwave
heating
provided
desired
product
within
1-4
minutes.
Moreover,
this
method
provides
easy
isolation
pure
products
simply
by
recrystallization,
use
chromatographic
purification
method.The
simplicity
neutrality
conditions,
post-reaction
workup,
higher
satisfactory
yield,
effectiveness,
diversity
substrates,
etc.
render
catalyst-based
protocol
stereoselective
highly
method.
has
been
found
safe
un-der
conditions
no
issues
have
faced
during
process.
Angewandte Chemie,
Год журнала:
2023,
Номер
135(43)
Опубликована: Июль 12, 2023
Abstract
Cyclodextrins
are
widely
used
as
carriers
of
small
molecules
for
drug
delivery
owing
to
their
remarkable
host
properties
and
excellent
biocompatibility.
However,
cyclic
oligosaccharides
with
different
sizes
shapes
limited.
Cycloglycosylation
ultra‐large
bifunctional
saccharide
precursors
is
challenging
due
the
constrained
conformational
spaces.
Herein
we
report
a
promoter‐controlled
cycloglycosylation
approach
synthesis
α‐(1→6)‐linked
mannosides
up
32‐mer.
thioglycosides
(
Z
)‐ynenoates
was
found
be
highly
dependent
on
promoters.
In
particular,
sufficient
amount
gold(I)
complex
played
key
role
in
proper
preorganization
transition
state,
providing
32‐mer
polymannoside,
which
represents
largest
synthetic
polysaccharide
date.
NMR
experiments
computational
study
revealed
that
2‐mer,
4‐mer,
8‐mer,
16‐mer,
adopted
states
shapes.
Research Square (Research Square),
Год журнала:
2023,
Номер
unknown
Опубликована: Дек. 13, 2023
Abstract
N-Glycosylated
heterocycles
play
important
roles
in
biological
systems
and
drug
development.
The
synthesis
of
these
compounds
heavily
relies
on
ionic
N-glycosylation,
which
is
usually
constrained
by
factors
like
labile
glycosyl
donors,
precious
metal
catalysts,
stringent
conditions.
Herein,
we
report
an
unprecedented
radical-based
method
for
synthesizing
N
-glycosides
leveraging
copper
metallaphotoredox
catalysis.
Complementing
with
the
well-established
approaches,
our
employs
inexpensive
photo-
copper-
catalysts
can
tolerate
some
extent
water.
Furthermore,
readily
available
stable
1-hydroxycarbohydrates
are
successfully
utilized
first
time
N-glycosylation.
reaction
exhibits
a
broad
substrate
scope,
encompassing
76
examples,
demonstrates
high
stereoselectivity,
favoring
1,2-trans
selectivity
furanoses
α-selectivity
pyranoses.
It
also
site-selectivity
substrates
containing
multiple
N-atoms.
synthetic
utility
was
showcased
through
late-stage
functionalization
bioactive
pharmaceuticals
Olaparib,
Axitinib,
Metaxalone.
Mechanistic
studies
proved
presence
intermediates
importance
