Synlett,
Journal Year:
2024,
Volume and Issue:
unknown
Published: June 25, 2024
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.
Research Square (Research Square),
Journal Year:
2024,
Volume and Issue:
unknown
Published: July 3, 2024
AbstractC-Glycosides
are
essential
for
the
study
of
biological
processes
and
development
carbohydrates-based
drugs.
Despite
tremendous
hurdles,
glycochemists
have
often
fantasized
efficient,
highly
stereoselective
synthesis
C-glycosides
with
shortest
steps
under
mild
conditions.
Herein,
we
report
a
desulfurative
radical
protocol
to
synthesize
C-alkyl
glycosides
coumarin
visible-light
induced
conditions
without
need
an
extra
photocatalyst,
in
which
stable
readily
available
glycosyl
thiols
that
could
be
obtained
intwo
or
three
from
native
sugars
activated
situ
by
pentafluoropyridine.
The
benefits
this
procedure
include
high
stereoselectivity,
broad
substrates
scope,
easily
handle.
Mechanistic
studies
indicated
produced
tetrafluoropyridyl
S-glycosides
formed
key
EDA
complexes
Hantzsch
ester
(for
C-alkyl
glycosides)
Et3N
coumarin
C-glycosides),
upon
irradiation
visible
light,
triggered
cascade
process
access
smoothly.
Beilstein Journal of Organic Chemistry,
Journal Year:
2024,
Volume and Issue:
20, P. 1973 - 1980
Published: Aug. 13, 2024
A
flow
photochemical
reaction
system
for
a
π-Lewis
acidic
metal-catalyzed
cyclization/radical
addition
sequence
was
developed,
which
utilizes
in
situ-generated
2-benzopyrylium
intermediates
as
the
photoredox
catalyst
and
electrophilic
substrates.
The
key
were
generated
through
intramolecular
cyclization
of
