ChemistrySelect,
Journal Year:
2023,
Volume and Issue:
8(10)
Published: March 7, 2023
Abstract
The
first
total
synthesis
of
capsular
polysaccharide
(CPS)
repeating
unit
[2)‐α‐
l
‐Rhap‐1→P→4‐β‐
d
‐ManpNAc‐(1→4)‐α‐
‐Glcp‐(1]
n
streptococcus
suis
serotype
8
is
reported.
key
features
the
are
formation
1,2
cis
glycosidic
linkage
between
mannosamine
and
glucose
derived
monomers
to
get
disaccharide
which
on
coupling
with
rhamnose
H‐phosphonate
followed
by
oxidation
P−H
bond
global
debenzylation
provide
targeted
trisaccharide
8.
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 31, 2025
We
herein
reported
a
catalytic,
minimally
protected,
and
highly
α-stereoselective
glycosylation
protocol
using
carboxylic
acid
as
an
acceptor
glycosyl
8-alkynyl-1-naphthoate
donor,
enabling
efficient
access
to
unprotected
α-1-O-
2-O-acyl
glycosides.
This
method
demonstrates
excellent
functional
compatibility
scope
generality,
allowing
for
the
of
wide
range
complex
acids.
Notably,
we
successfully
synthesized
two
natural
products,
α-penta-O-galloyl-d-glucopyranose
nyctanthesin
A,
this
protocol.
Mechanistic
studies
highlighted
crucial
role
1-O
ester
functionality
in
ensuring
chemoselectivity
important
contribution
2-O
facilitating
reaction.
Angewandte Chemie,
Journal Year:
2024,
Volume and Issue:
136(21)
Published: March 26, 2024
Abstract
Herein,
we
demonstrate
the
robustness
of
a
synergistic
chiral
Pd/organoboron
system
in
tackling
challenging
suite
site‐,
regio‐,
enantio‐
and
diastereoselectivity
issues
across
considerable
palette
biologically
relevant
carbohydrate
polyols,
when
prochiral
alkoxyallenes
were
employed
as
electrophiles.
In
view
burgeoning
role
noncovalent
interactions
(NCIs)
stereoselective
synthesis,
our
mechanistic
experiments
DFT
modeling
reaction
path
unexpectedly
revealed
that
NCIs
such
hydrogen
bonding
CH‐π
between
resting
states
Pd‐π‐allyl
complex
borinate
saccharide
are
critically
involved
stereoselectivity
control.
Our
strategy
thus
illuminates
untapped
potential
harnessing
context
transition
metal
catalysis
to
tackle
challenges
functionalization.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(21)
Published: March 26, 2024
Abstract
Herein,
we
demonstrate
the
robustness
of
a
synergistic
chiral
Pd/organoboron
system
in
tackling
challenging
suite
site‐,
regio‐,
enantio‐
and
diastereoselectivity
issues
across
considerable
palette
biologically
relevant
carbohydrate
polyols,
when
prochiral
alkoxyallenes
were
employed
as
electrophiles.
In
view
burgeoning
role
noncovalent
interactions
(NCIs)
stereoselective
synthesis,
our
mechanistic
experiments
DFT
modeling
reaction
path
unexpectedly
revealed
that
NCIs
such
hydrogen
bonding
CH‐π
between
resting
states
Pd‐π‐allyl
complex
borinate
saccharide
are
critically
involved
stereoselectivity
control.
Our
strategy
thus
illuminates
untapped
potential
harnessing
context
transition
metal
catalysis
to
tackle
challenges
functionalization.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(26), P. 17629 - 17635
Published: June 23, 2024
The
total
synthesis
and
structural
elucidation
of
the
antimicrobial
sactipeptide
enteropeptin
A
is
reported.
Enteropeptin
contains
a
thioaminoketal
group
with
an
unassigned
stereochemical
configuration
that
embedded
in
highly
unusual
thiomorpholine
ring.
In
this
synthesis,
linear
peptide
containing
dehydroamino
acid
pendant
cysteine
residue
subjected
to
Markovnikov
hydrothiolation
by
dithiophosphoric
catalyst.
This
cyclization
reaction
forms
central
ring
found
enteropeptins.
Both
diastereomers
at
stereocenter
were
prepared,
their
comparison
authentic
standard
allowed
for
unambiguous
assignment
natural
product
be
D
configuration.
inaugural
represents
first
reported
date.
Moreover,
strategy
disclosed
herein
serves
as
general
platform
stereochemically
defined
thiomorpholine-containing
peptides,
which
may
enable
discovery
new
cyclic
antibiotics.
The Journal of Organic Chemistry,
Journal Year:
2023,
Volume and Issue:
88(23), P. 16467 - 16484
Published: Nov. 9, 2023
This
article
describes
the
development
of
a
recyclable
polystyrene-based
phosphonic
acid
resin
and
its
use
for
synthesis
immobilized
glycosyl
phosphonate
donors
subsequent
glycosylation
reaction.
solid
support
was
generated
on
decagram
scale
from
commercially
available
Merrifield
subsequently
functionalized
via
two
different
methods
into
eight
glycosylphosphonates.
The
resultant
glycosylphosphonate-containing
resins
were
obtained
in
59–96%
yields
found
to
be
bench-stable
at
room
temperature.
These
could
activated
using
trifluoroborane
etherate
80
°C
react
with
various
alcohol-
thiol-based
acceptors
provide
17
glycosides
good-to-excellent
(53–98%).
In
addition,
it
demonstrated
that
glycosylated
recovered
recycled
multiple
times
regenerate
glycosylphosphonate
subjected
on-resin
glycan
elongation.
International Journal of Chemistry and Technology,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Aug. 6, 2024
Biopolymers
have
become
more
and
attractive
nowadays
for
both
experimental
theoretical
studies
because
of
their
importance
in
our
daily
life.
In
this
contribution,
the
electronic
properties
reactivity
behavior
some
biomonomers;
chitin
chitosan
been
thoroughly
investigated
theoretically
using
density
functional
theory
(DFT)
B3LYP/6-31G(d)
level
theory.
The
regioselectivity
these
molecules
has
rationalized
by
Fukui
Parr
indices
order
to
explain
show
most
probable
sites
be
attacked
towards
nucleophiles
electrophiles.
For
three
studied
monomers,
oxygen
nitrogen
atoms
were
found
reactive
sites.
functions
complementary
while
explaining
possible
regioselectivity.
Photosynthetica,
Journal Year:
2021,
Volume and Issue:
59(4), P. 587 - 599
Published: Nov. 18, 2021
Synechococcus
is
one
of
the
most
abundant
photoautotrophic
picoplankton
in
marine
ecosystem.
However,
it
not
clear
how
assemblages
respond
to
light
intensity
variation
a
genus
group.
Here,
enriched
from
situ
coastal
seawater
were
subjected
simulation
experiments
range
9-243
μmol(photon)
m-2
s-1.
Characteristics
concerning
physiology,
genomics,
and
metatranscriptomics
analyzed.
Physiologically,
fitting
model
predicted
photosynthesis
indications
pigment
contents
increased
with
different
trends
following
intensity.
Genomic
sequencing
demonstrated
that
both
phylogenetic
phenotypic
compositions
assemblage
exhibited
population
succession.
Especially,
proportion
type
2
was
changed
significantly.
In
metatranscriptomics,
genes
downregulated
high-light
group,
while
photosynthesis-related
entirely
upregulated.
The
high
upregulation
genes,
such
as
psbO,
psbA,
apcB,
cpcB,
corresponded
succession
genotype
responsible
for
physiological
shift
response
