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.
Journal of Carbohydrate Chemistry,
Год журнала:
2024,
Номер
43(1-2), С. 21 - 36
Опубликована: Фев. 12, 2024
Gold-catalyzed
glycosylation
using
alkyne
donors
is
a
versatile
approach
for
the
efficient
assembly
of
diverse
types
glycosides
due
to
its
catalytic
and
mild
properties.
Minor
structural
alterations
might
significantly
affect
reaction
when
alkyne-based
leaving
groups
are
simplified.
By
mapping
reactivities
series
structurally
simplified
donors,
herein
we
demonstrate
role
each
characteristic
functional
group
glycosyl
ynenoates.
Based
on
isolation
X-ray
diffraction
characterization
pyran-5-ylgold(I)
complex
generated
from
group,
plausible
mechanism
gold(I)-catalyzed
with
ynenoates
as
was
proposed.
Organic Letters,
Год журнала:
2023,
Номер
25(19), С. 3548 - 3552
Опубликована: Май 9, 2023
Rapid
synthesis
of
saccharides
by
a
chemical
method
is
an
efficient
way
to
meet
the
demand
for
well-defined
glycans
probe
their
biological
functions.
Herein,
feasible
and
convenient
strategy
saccharide
was
established
introducing
photosensitive
fluorous
tag
at
anomeric
position
glycosides.
The
used
not
only
in
polytetrafluoroethylene-assisted
rapid
purification
but
also
as
temporary
protecting
group
reducing
end
carbohydrates.
tag-protected
glycosides
could
be
transformed
into
new
glycosyl
donors
convergent
after
orthogonal
deprotection
photolysis.
Via
combination
β-directing
C-5
carboxylate
glycosylation
strategy,
β-1,4-mannuronates
were
efficiently
prepared.
Abstract
Chikusetsusaponin
IVa
butyl
ester
(CS-IVa-Be)
is
a
triterpene
saponin
that
acts
as
novel
IL6R
antagonist
for
inducing
breast
cancer
cell
apoptosis.
However,
the
structure–activity
relationship
this
class
of
saponins
remains
unclear.
Here,
we
report
gram-scale
synthesis
CS-IVa-Be
and
efficient
preparation
eight
its
analogues.
was
demonstrated
to
have
significant
antitumor
activities
against
MDA-MB-231,
HepG2,
A549
cells.
When
one
sugar
residues
at
either
3-OH
or
28-COOH
position
cleaved,
length
alkyl
chain
on
d-glucuronic
acid
residue
changed,
these
analogues
showed
varied
inhibitory
lines.
Notably,
carboxylic
form
exhibited
stronger
activity
MDA-MB-231
Furthermore,
inhibited
proliferation
in
dose-dependent
manner
by
arresting
cycle
G2/M
phase.
European Journal of Organic Chemistry,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 12, 2024
Abstract
Sodium
oligomannate,
a
sophisticated
mixture
of
acidic
linear
β‐(1,4)‐
d
‐oligomannurarate
ranging
from
dimers
to
decamers
with
an
average
molecular
weight
670∼880
Da,
has
gained
conditional
approval
for
the
treatment
Alzheimer's
disease.
Herein,
we
develop
efficient
approach
chemical
synthesis
well‐defined
‐mannurarate
di‐,
tetra‐,
hexa‐
and
octasaccharides
(
1–4
),
utilizing
N
‐phenyl
trifluoroacetimidate
donors
thioglycoside
acceptors
stereoselective
assembly
desired
‐mannuronate
linkages.
This
features
straightforward
protecting
group
strategy
only
two
types
groups:
tert
‐butyldimethylsilyl
(TBS)
4‐OH
at
non‐reducing
end
benzyl
(Bn)
free
hydroxyl
carboxylic
acid
moieties,
thereby
ensuring
formation
β‐mannosyl
bonds
facilitating
sequential
transformation
into
target
oligosaccharides.
The
scalability
present
these
oligosaccharides
paves
way
in‐depth
structure‐activity
relationship
studies
pharmacological
investigations
sodium
oligomannates.
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.
