The Chemical Record,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 27, 2024
Carbohydrates
are
natural,
renewable,
chemical
compounds
that
play
crucial
roles
in
biological
systems.
Thus,
efficient
and
stereoselective
glycosylation
is
an
urgent
task
for
the
preparation
of
pure
structurally
well-defined
carbohydrates.
Photoredox
catalysis
has
emerged
as
a
powerful
tool
carbohydrate
chemistry,
providing
alternative
addressing
some
challenges
glycochemistry.
Over
last
few
decades,
Ir-
Ru-based
organometallic
photocatalysts
have
attracted
significant
interest
because
their
high
stability,
high-energy
triplet
state,
strong
visible-light
absorption,
long
luminescence
lifetime,
amenability
to
ligand
modification.
This
review
highlights
recent
progress
photocatalyst-promoted
synthesis
modification
carbohydrates
under
photoirradiation,
well
related
benefits
drawbacks.
ACS Catalysis,
Год журнала:
2024,
Номер
14(15), С. 11532 - 11544
Опубликована: Июль 19, 2024
Glycosyl
donor
activation
emerged
as
an
enabling
technology
for
anomeric
functionalization,
but
aimed
primarily
at
O-glycosylation.
In
contrast,
we
herein
disclose
mechanistically
distinct
electrochemical
glycosyl
bromide
activations
via
halogen-atom
transfer
and
C-glycosylation.
The
radical
addition
to
alkenes
led
C-alkyl
glycoside
synthesis
under
precious
metal-free
reaction
conditions
from
readily
available
bromides.
robustness
of
our
e-XAT
strategy
was
further
mirrored
by
C-aryl
C-acyl
glycosides
assembly
through
nickela-electrocatalysis.
Our
approach
provides
orthogonal
with
expedient
scope,
hence
representing
a
general
method
direct
C-glycosides
assembly.
ACS Catalysis,
Год журнала:
2024,
Номер
unknown, С. 17727 - 17738
Опубликована: Ноя. 18, 2024
We
demonstrate
an
efficient,
scalable,
and
stereoselective
C-glycosylation
with
thioglycosides
possessing
a
unique
photoactive
tetrafluoropyridin-4-yl
(TFPy)
thio
radical
leaving
group,
affording
editable
medicinally
biologically
essential
C-α-glucogallin
derivatives.
In
the
presence
of
silyl
enol
ether
acceptors,
desulfurative
coupling
reaction
performs
smoothly
under
mild
conditions
upon
exposure
to
blue
light
irradiation.
This
versatile
protocol
permits
synthesis
sugar-drug
chimeras
by
C1
ketonylation
complex
drug-derived
ethers.
The
scale-up
synthesis,
anomeric
epimerization,
post-C-glycosylation
modification
ketone
sugars
showcase
reaction's
potential
utilities.
Furthermore,
could
be
applied
direct
carbohydrate
skeleton
editing
equipping
group
on
nonanomeric
position.
is
viable
for
unprotected
TFPy
thioglycoside,
route
ketonyl
sugars.
concise
six-step
assembly
both
configurated
C-glucogallins
from
commercially
cheap
glucose
pentaacetate
their
antioxidant
reactivity
investigations
underline
promising
medicinal
relevance
our
current
protocols.
mechanism
was
investigated
through
trapping
experiment,
oxocarbenium
fluorescence
quenching
Stern–Volmer
analysis,
confirming
that
major
glycosyl
intermediates
are
generated
thioglycoside
donors,
whose
effectively
quench
excited
Ir(ppy)3
oxidative
process,
complementary
product,
accounting
examples
moderate
selectivities.
The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(17), С. 11909 - 11920
Опубликована: Авг. 9, 2024
Melibiosamine
(Gal-α(1,6)-GlcNH2),
consisting
of
galactose
and
glucosamine
linked
by
an
α(1,6)-glycosidic
bond,
is
artificial
disaccharide
derivative
that
selectively
inhibits
the
proliferation
K562
tumor
cells
relative
to
HUC-F2
normal
cells.
In
this
study,
we
employed
a
linkage-editing
strategy
synthesize
CH2-
CHF-linked
melibiosamine
analogs
through
chemo-
stereoselective
hydrogenation
fluorovinyl-C-glycoside.
(R)-CHF-Melibiosamine
exhibited
more
potent
antiproliferative
activity
than
O-linked
melibiosamine,
while
(S)-CHF-melibiosamine
was
less
potent.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(47), С. 32269 - 32275
Опубликована: Ноя. 15, 2024
Radical
C-glycosylation
presents
a
flexible
and
efficient
method
for
synthesizing
C-glycosides.
Existing
methods
always
require
multistep
processes
generating
anomeric
radicals.
In
this
study,
we
introduce
streamlined
approach
to
produce
radicals
through
direct
C-OH
bond
homolysis
of
unmodified
saccharides,
eliminating
the
need
protection,
deprotection,
or
activation
steps.
These
selectively
couple
with
activated
alkenes,
yielding
products
high
stereoselectivity
(>20:1).
This
is
applicable
variety
native
monosaccharides,
such
as
l-arabinose,
d-arabinose,
d-xylose,
l-xylose,
d-galactose,
β-d-glucose,
α-d-glucose,
l-ribose,
well
oligosaccharides
including
α-lactose,
d-(+)-melibiose,
acarbose.
We
also
extend
amino
acid
peptide
derivatives,
demonstrate
synthesis
an
anti-inflammatory
agent.
Chemical Communications,
Год журнала:
2024,
Номер
60(66), С. 8684 - 8687
Опубликована: Янв. 1, 2024
Photochemical
multi-component
coupling
reactions
initiated
by
the
activation
of
glycosyl
bromides
in
presence
1,4-bis(diphenylamino)benzene
(BDB)
as
an
organic
photocatalyst
were
developed.
Organic Chemistry Frontiers,
Год журнала:
2024,
Номер
11(15), С. 4194 - 4206
Опубликована: Янв. 1, 2024
We
described
here
comprehensive
studies
on
Zn/F
carbenoids.
carbenoids
were
found
to
be
stable
and
useful
nucleophilic
monofluoroalkylating
reagents,
providing
a
new
synthetic
route
functionalized
monofluroalkanes.
Abstract
C-Aryl
glycosides
have
attracted
considerable
interest
as
biologically
active
natural
products
and
O-aryl
glycoside
mimetics
in
drug
discovery.
Here,
we
describe
a
straightforward
synthesis
of
C-aryl
by
photoredox/Ni
dual-catalyzed
reductive
cross-coupling
between
glycosyl
bromides
aryl
bromides.
This
methodology
enables
highly
α-stereoselective
glucosides,
galactosides,
mannosides.
Molecules,
Год журнала:
2024,
Номер
29(19), С. 4710 - 4710
Опубликована: Окт. 4, 2024
An
efficient
and
versatile
glycosylation
methodology
is
crucial
for
the
systematic
synthesis
of
oligosaccharides
glycoconjugates.
A
direct
intermolecular
an
indirect
intramolecular
have
been
developed,
former
can
be
applied
to
medium-to-long-chain
glycans
like
that
nucleotides
peptides.
The
development
a
generally
applicable
approach
stereoselective
construction
glycosidic
bonds
remains
major
challenge,
especially
1,2-
