The
study
introduces
a
previously
unidentified
method
for
amide
bond
formation
that
addresses
several
limitations
of
conventional
approaches.
It
uses
the
β-silyl
alkynoate
molecule,
where
alkynyl
group
activates
ester
efficient
formation,
while
bulky
TIPS
(triisopropylsilane)
prevents
unwanted
1,4-addition
reactions.
This
approach
exhibits
high
chemoselectivity
amines,
making
compatible
with
wide
range
substrates,
including
secondary
and
targets
specific
ε-amino
lysine
among
native
amino
ester’s
derivatives.
maintains
stereochemistry
during
removal,
allowing
versatile
platform
postsynthesis
modifications
such
as
click
reactions
peptide-drug
conjugations.
These
advancements
hold
substantial
promise
pharmaceutical
development
peptide
engineering,
opening
avenues
research
applications.
Organic Chemistry Frontiers,
Год журнала:
2024,
Номер
11(8), С. 2351 - 2374
Опубликована: Янв. 1, 2024
This
review
carefully
summarizes
the
advances
achieved
in
catalytic
hydrofunctionalization
of
ynamides
and
is
categorized
by
bond
formation
type
including
C−C,
C−X,
C−O,
C−N,
C−S,
C−P,
C−Si,
C−Ge
bonds.
Organic Letters,
Год журнала:
2024,
Номер
26(38), С. 8121 - 8127
Опубликована: Сен. 16, 2024
We
developed
an
organophotoredox
catalytic
system
to
facilitate
the
decarboxylative
allylation
coupling
process
concerning
α-amino
acids
and
related
C-terminal
carboxylate
peptides
using
Morita-Baylis-Hillman
adducts
as
allylic
precursors.
This
metal-free
method
operates
under
mild
conditions
is
compatible
with
various
amino
acids.
The
versatility
of
this
protocol,
particularly
in
chemical
biology
research,
has
been
preliminarily
demonstrated
through
ligation
bioactive
peptide
chains.
Organic Process Research & Development,
Год журнала:
2023,
Номер
27(5), С. 982 - 992
Опубликована: Май 4, 2023
Diisopropylcarbodiimide
(DIC)
constitutes
one
of
the
most
widely
used
coupling
reagents
for
amide
bond
formation
in
peptide
synthesis.
We
have
previously
reported
that
DIC
contains
a
varying
amount
sulfur
(61–2030
ppm),
and
main
S-containing
impurity
is
thiourea
DITU,
which
exhibits
an
excellent
ability
to
suppress
side
reactions
caused
by
N-oxyl
radicals
formed
from
common
N-hydroxyl-coupling
additives
such
as
HOBt
Oxyma
(Green
Chem.
2019,
21,
5990).
Aiming
understand
how
quality
impacts
synthesis,
here,
we
report
evaluation
14
batches
GMP-grade
seven
different
vendors.
With
elemental
analysis
(S),
gas
chromatography–mass
spectrometry,
high-performance
liquid
chromatography,
chromatography-mass
nuclear
magnetic
resonance,
determined
currently
use
not
but
rather
diazetidine-2-thione
[1,3-diisopropyl-4-(isopropylimino)-1,3-diazetidine-2-thione,
DIDT],
2
+
cycloaddition
between
iPr-NCS.
The
identity
DIDT
was
confirmed
synthesis
iPr-NCS,
followed
spiking
batch
with
synthesized
material.
In
comparative
DITU
aimed
at
determining
their
breakdown
Fmoc-Cys(Trt)-OH
Oxyma,
completely
prevented
Cys
decomposition,
whereas
had
no
effect
on
suppression
amino
acid.
Finally,
catalytic
amounts
well
thiols
DTT
NAC
positive
minimization
HOBt-induced
Fmoc-Trp(Boc)-OH,
urea
DIU,
every
DIC-mediated
reaction,
accelerated
Trp
substrate.
Journal of Materials Chemistry B,
Год журнала:
2023,
Номер
11(37), С. 8834 - 8847
Опубликована: Янв. 1, 2023
The
rational
design
and
engineering
strategies,
employed
in
polypeptide/protein
vesicles,
from
synthesis
to
assembly,
for
advanced
biological
medical
applications.
Over
the
past
few
decades,
peptide/protein
synthesis
and
bio-conjugation
has
gained
increasing
interest
in
research
community
owing
to
high
demand
for
strategies
that
provide
modified
protein
adducts
a
site-selective
fashion.
Herein,
we
report
novel
approach
combines
Passerini
multicomponent
reaction
chemo-enzymatic
peptide
(CEPS)
selective
of
C-termini.
The
utilizes
aqueous
acidic
buffer
conditions
establish
chemoselectivity
carboxylic
acids,
while
subsequent
enzymatic
ligation
selectively
targets
formed
C-terminal
substrates.
We
functionalized
diverse
set
pentapeptides
utilizing
numerous
isocyanide
car-bonyl
compounds
successfully
performed
ligations.
This
combined
chemoenzymatic
method
therefore
represents
valuable
technology
future
into
modification
peptides/proteins.
The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(11), С. 7598 - 7608
Опубликована: Май 28, 2024
A
method
for
the
syntheses
of
isolable,
active
esters
is
described
in
which
carboxylic
acids
are
treated
with
triphenylphosphine,
iodine,
and
triethylamine.
Active
accessible
this
way
include
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
unknown
Опубликована: Окт. 16, 2024
Readily
accessible,
racemic
N-carboxyanhydrides
(NCAs)
of
α-amino
acids
underwent
a
deracemization
reaction
upon
irradiation
at
λ=366
nm
in
the
presence
chiral
benzophenone
catalyst.
The
enantioenriched
NCAs
(up
to
98
%
ee)
serve
as
activated
acid
surrogates
and,
due
their
instability,
they
were
directly
converted
into
consecutive
products.
N-Protected
esters
obtained
after
with
MeOH
and
N-benzoylation
(14
examples,
70
%-quant.,
82-96
ee).
Other
reactions
included
amide
(ten
65
90-98
peptide
(three
75-89
%,
d.
r.=97/3
94/6)
bond
formation.
Limitations
method
relate
for
some
issues
solubility,
photooxidation,
high
configurational
lability.
Asian Journal of Organic Chemistry,
Год журнала:
2023,
Номер
12(9)
Опубликована: Июль 27, 2023
Abstract
A
novel
and
unique
activation
method
for
esters
possessing
a
non‐activated
cyclopropyl
moiety
as
potential
activating
group
is
developed
acyl
fluoride
generation
using
hypervalent
iodine(III)
reagent
Selectfluor.
The
resulting
fluoride,
which
versatile
synthetic
intermediate,
was
smoothly
transformed
into
the
various
carbonyl
compounds,
in
particular,
amides.
This
protocol
can
be
applied
to
chemoselective
of
diester
compounds.
Advanced Synthesis & Catalysis,
Год журнала:
2024,
Номер
366(11), С. 2507 - 2513
Опубликована: Апрель 19, 2024
Abstract
Hydrocarboxylation
of
methyl
2‐octynoate,
a
chemical
commercially
available
at
low
cost,
with
N
‐protected
amino
acids
was
developed
gold‐zinc
cooperative
catalyst
constructed
5‐[(2,2′‐bipyridin)‐5‐yl]imidazo[1,5‐
]pyridin‐3‐ylidene
to
prepare
α‐methoxycarbonyl
enol
esters
as
acylating
reagents.
The
were
isolable
through
silica‐gel
column
chromatography
and
storable
without
precautions
regarding
moisture.
Acylation
free
amines
the
proceeded
epimerization
stereogenic
center
derived
from
esters,
affording
analytically
pure
dipeptide
compounds
filtration
hexane‐washing.
