Organic & Biomolecular Chemistry,
Journal Year:
2023,
Volume and Issue:
21(27), P. 5516 - 5520
Published: Jan. 1, 2023
C-Glycosyl
compounds
have
gained
considerable
attention
over
the
last
few
decades
due
to
their
high
chemical
stability
and
promising
applications
in
drug
discovery.
Herein
we
disclose
an
operationally
simple,
metal-free,
photocatalytic
approach
for
glycosylation
of
azomethine
imines
using
4-glycosyl-1,4-dihydropyridines
(DHPs)
as
radical
precursors.
The
protocol
features
mild
reaction
conditions,
scalability,
broad
substrate
scope,
good
functional
group
tolerance.
Moreover,
resulting
pyrazolidinone
moiety
can
be
easily
deprotected,
acylated
or
reduced
into
a
glycosyl
β-alanine
analog.
Chemical Reviews,
Journal Year:
2023,
Volume and Issue:
123(8), P. 4237 - 4352
Published: Jan. 24, 2023
The
emergence
of
modern
photocatalysis,
characterized
by
mildness
and
selectivity,
has
significantly
spurred
innovative
late-stage
C–H
functionalization
approaches
that
make
use
low
energy
photons
as
a
controllable
source.
Compared
to
traditional
strategies,
photocatalysis
paves
the
way
toward
complementary
and/or
previously
unattainable
regio-
chemoselectivities.
Merging
compelling
benefits
with
workflow
offers
potentially
unmatched
arsenal
tackle
drug
development
campaigns
beyond.
This
Review
highlights
photocatalytic
strategies
small-molecule
drugs,
agrochemicals,
natural
products,
classified
according
targeted
bond
newly
formed
one.
Emphasis
is
devoted
identifying,
describing,
comparing
main
mechanistic
scenarios.
draws
critical
comparison
between
established
ionic
chemistry
photocatalyzed
radical-based
manifolds.
aims
establish
current
state-of-the-art
illustrate
key
unsolved
challenges
be
addressed
in
future.
authors
aim
introduce
general
readership
functionalization,
specialist
practitioners
evaluation
methodologies,
potential
for
improvement,
future
uncharted
directions.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(38)
Published: June 7, 2023
Glycosyl
radical
functionalization
is
one
of
the
central
topics
in
synthetic
carbohydrate
chemistry.
Recent
advances
metal-catalyzed
cross-coupling
chemistry
and
metallaphotoredox
catalysis
provided
powerful
platforms
for
glycosyl
diversification.
In
particular,
discovery
new
precursors
conjunction
with
these
advanced
reaction
technologies
have
significantly
expanded
space
compound
synthesis.
this
Review,
we
highlight
most
recent
progress
area
starting
from
2021,
reports
included
will
be
categorized
based
on
different
types
better
clarity.
Accounts of Chemical Research,
Journal Year:
2023,
Volume and Issue:
56(18), P. 2473 - 2488
Published: Aug. 18, 2023
ConspectusThe
study
of
carbohydrates
has
emerged
as
a
crucial
research
area
in
various
disciplines
due
to
their
pivotal
roles
cellular
processes.
To
facilitate
in-depth
exploration
biological
functions,
chemical
glycosylation
reactions
that
allow
facile
access
glycoconjugates
broad
community
are
highly
needed.
In
classical
reactions,
glycosyl
donor
is
activated
by
an
acid
generate
reactive
electrophilic
intermediate,
which
subsequently
forms
glycosidic
bond
upon
reaction
with
nucleophilic
acceptor.
Such
ionic
pathway
been
the
mainstay
technique
for
glycoconjugate
synthesis
and
allowed
numerous
intricate
structures.
Nevertheless,
limitations
still
exist.
For
instance,
when
labile
donors
or
harsh
activating
conditions
required,
these
methods
show
limited
tolerance
hydroxyl
groups
abundant
on
sugar
rings.
addition,
achieving
good
stereocontrol
represents
another
longstanding
obstacle.
recent
years,
new
modes
activation
have
sought
tackle
above
challenges.We
noted
passing
through
intermediacy
radicals
via
cascade
single-electron
transfer
steps
possess
significant
but
underexplored
potential.
Progress
this
slow
large
part
dearth
handy
maneuver
radicals.
Most
existing
call
either
forcing
unstable/inconvenient
starting
materials.
order
better
exploit
power
radical
glycosylation,
we
developed
range
donors─namely,
sulfoxides,
sulfones,
sulfinates─that
bench
stable
can
be
readily
prepared
from
simple
These
form
under
mild
conditions.
Enabled
use
donors,
series
could
used
making
O-,
S-,
C-glycosides,
some
were
previously
difficult
access.
many
cases,
no
protecting
group
required.
As
illustration
potential
utility,
our
adopted
preparation
sugar–drug
conjugates,
sugar–DNA
glycopeptides,
even
glycoproteins.
While
most
cases
intrinsic
reactivity
intermediates
explored
axially
configured
products,
also
utilization
external,
delicate
reagents,
catalysts
override
such
innate
preference
achieve
catalyst-controlled
stereoselectivity.We
believe
enormous
inspire
development
novel
glycoside
synthesis.
Account,
highlight
design
principles
summarize
advancements
enabled
use,
provide
outlook
future
directions
field.
Chemical Science,
Journal Year:
2024,
Volume and Issue:
15(4), P. 1204 - 1236
Published: Jan. 1, 2024
This
review
article
highlights
the
diverse
ways
in
which
recent
developments
areas
of
photocatalysis
and
visible
light
photochemistry
are
impacting
synthetic
carbohydrate
chemistry.
Chemical Society Reviews,
Journal Year:
2023,
Volume and Issue:
52(16), P. 5373 - 5387
Published: Jan. 1, 2023
The
chemistry
and
the
reaction
mechanisms
behind
four
catalytic
protocols
currently
available
for
visible
light-induced
C–C
cross-coupling
by
activation
of
C
sp
3
–H
bonds
are
described.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
146(1), P. 824 - 832
Published: Dec. 20, 2023
Glucose
and
its
polyhydroxy
saccharide
analogs
are
complex
molecules
that
serve
as
essential
structural
components
in
biomacromolecules,
natural
products,
medicines,
agrochemicals.
Within
the
expansive
realm
of
saccharides,
a
significant
area
research
revolves
around
chemically
transforming
naturally
abundant
units
to
intricate
or
uncommon
such
oligosaccharides
rare
sugars.
However,
partly
due
presence
multiple
hydroxyl
groups
with
similar
reactivities
complexities
arising
from
stereochemistry,
transformation
unprotected
sugars
desired
target
remains
challenging.
One
formidable
challenge
lies
efficient
selective
activation
modification
C–O
bonds
saccharides.
In
this
study,
we
disclose
modular
2-fold
"tagging–editing"
strategy
allows
for
direct
editing
enabling
rapid
preparation
valuable
drug
derivatives.
The
first
step,
referred
"tagging",
involves
catalytic
site-selective
installation
photoredox
active
carboxylic
ester
group
specific
unit
an
sugar.
second
namely,
"editing",
features
bond
cleavage
form
carbon
radical
intermediate
undergoes
further
transformations
C–H
C–C
formations.
Our
constitutes
most
effective
shortest
route
medicines
other
bearing
Chem Catalysis,
Journal Year:
2024,
Volume and Issue:
4(3), P. 100891 - 100891
Published: Jan. 18, 2024
Harnessing
modern
catalytic
concepts
to
address
long-standing
challenges
in
carbohydrate
chemistry
has
garnered
substantial
interest
from
the
synthetic
community
recent
years.
In
particular,
usage
of
multiple
catalysts
for
sequential
one-pot
relay
reactions
already
contributed
major
benefits
accessing
oligosaccharides
past
two
decades.
contrast,
exploitation
synergistic
catalysis
glycosciences
is
only
its
infancy.
While
methods
combine
stepwise
into
a
single
flask
operation,
they
do
not
intrinsically
alter
reaction
mechanisms.
Conversely,
involves
creation
unique
mechanistic
pathways
by
merging
cycles.
At
nexus
cycles,
fertile
opportunities
arise
bond-forming
strategies
that
are
possible
within
individual
manifold.
The
realization
underexploited
potential
expected
accelerate
developments
field,
thereby
offering
stereoselective
entry
points
glycosidic
chemical
space
was
previously
inaccessible.
Advanced Synthesis & Catalysis,
Journal Year:
2023,
Volume and Issue:
365(17), P. 2818 - 2849
Published: July 7, 2023
Abstract
In
the
last
fifteen
years,
development
of
visible‐light
photocatalysis,
metal/photoredox
dual
catalysis
has
become
forefront
as
a
new
paradigm
in
organic
synthesis
well
carbohydrate
chemistry.
It
led
to
discovery
unprecedented
transformations
and
also
improvement
known
reactions
under
mild
conditions,
employing
simple
household
light
sources
bench‐stable
precursors,
which
meet
requirements
green
chemistry
sustainable
excellent
yield
stereocontrol.
general
sense,
exploitation
photoredox
hinges
on
capability
photocatalyst
or
redox
mediator
transform
visible
into
chemical
energy
via
photo‐irradiated
SET
(single
electron
transfer),
PET
(photoinduced
HAT
(hydrogen
atom
XAT
(halogen
transfer)
potentially
unlock
unique
reaction
pathways,
thereby
generating
diverse
array
reactive
intermediates.
view
type,
mechanism,
status,
this
review
will
systematically
summarize
latest
advances
visible‐light‐promoted
photocatalytic
glycosylation
reactions,
are
driven
by
single
photoactivity
donor‐acceptor
(EDA)
complexes.
