Crystal Growth & Design,
Год журнала:
2024,
Номер
24(9), С. 3967 - 3976
Опубликована: Апрель 15, 2024
Understanding
the
interplay
of
structural
features
responsible
for
molecular
assembly
is
essential
crystal
engineering.
When
assembling
molecules
with
encoded
motifs,
first
choice
supramolecular
strategies
almost
always
include
robust
directional
nonbonded
contacts.
Quasiracemic
materials,
considered
near
racemates
since
cocrystallization
occurs
chemically
unique
components,
lack
a
framework
or
functional
group
restrictions,
highlighting
importance
shape
to
assembly.
Recently,
our
reported
quasiracemates
derived
from
benzoyl
leucine/phenylalanine
derivatives
two
points
chemical
difference.
In
this
study,
we
modified
valine
and
increased
scope
work
by
imposing
larger
variance
in
side
chain
substituents.
Pairing
CF3
component
quasienantiomers
that
differ
iteratively
hydrogen
t-butyl
offers
an
important
view
into
landscape
these
materials.
Single-crystal
X-ray
crystallography
lattice
energy
assessments,
coupled
conformational
structure
similarity
searches,
show
elevated
degree
isomorphism
many
targeted
17
quasiracemates.
These
amino
acid
architectures
create
extended
hydrogen-bond
patterns
provide
enhanced
opportunities
study
space
recognition
profiles
diverse
family
quasienantiomeric
components.
Chemical Science,
Год журнала:
2024,
Номер
15(11), С. 3980 - 3987
Опубликована: Янв. 1, 2024
The
origin
of
the
electrophilicity
a
series
cyclohexanones
and
benzaldehydes
is
investigated
using
activation
strain
model
quantitative
Kohn–Sham
molecular
orbital
(MO)
theory.
Abstract
Isomorphic
substitution
of
zeolites
with
B,
Al
and
Ga
is
a
widely
used
approach
in
catalysis.
The
experimentally
reported
trend
their
acidities
decreases
the
order:
Al>Ga>B.
However,
consistent
explanation
still
lacking
literature.
To
bring
more
understanding
this
trend,
density
functional
theory
computations
were
conducted
on
several
model
systems.
First,
acidity
small
clusters
two
(2T)
five
(5T)
tetrahedral
sites
was
analyzed.
These
systems
then
projected
onto
three
large
void
structures:
H‐[A]‐BEA
(52T),
H‐[A]‐FAU
(84T)
H‐[A]‐MOR
(112T)
A=B,
Al,
Ga.
Our
electron
Interacting
Quantum
Atom
analyses
show
that
originates
from
much
stronger
O−Al
bond,
which
dominated
by
electrostatic
attraction.
bridging
hydroxyl
therefore
donates
charge
to
metal,
proton
becomes
positive
consequently
acidic.
are
acidic
than
B
due
greater
covalent
nature
O−Ga
bond.
resulting
acidity,
as
seen
ammonia,
depends
both
oxygen
distribution
surrounding
oxygens
exerted
substituents.
Topics in Current Chemistry,
Год журнала:
2024,
Номер
382(2)
Опубликована: Май 10, 2024
Computational
organic
chemistry
has
become
a
valuable
tool
in
the
field
of
bioorthogonal
chemistry,
offering
insights
and
aiding
progression
this
branch
chemistry.
In
review,
I
present
an
overview
computational
work
field,
including
exploration
both
primary
analysis
methods
used
their
application
main
areas
chemistry:
(3
+
2)
[4
2]
cycloadditions.
context
cycloadditions,
detailed
studies
electronic
effects
have
informed
evolution
cycloalkyne/1,3-dipole
Through
techniques,
researchers
found
ways
to
adjust
structure
via
hyperconjugation
enhance
reactions
without
compromising
stability.
For
such
as
distortion/interaction
energy
decomposition
been
beneficial,
leading
development
reactants
with
improved
reactivity
creation
orthogonal
reaction
pairs.
To
conclude,
touch
upon
emerging
fields
cheminformatics
machine
learning,
which
promise
play
role
future
discovery
optimization.
Structural Dynamics,
Год журнала:
2024,
Номер
11(2)
Опубликована: Март 1, 2024
With
the
availability
of
computer
readable
information
in
Cambridge
Structural
Database
(CSD),
wide
ranging,
largely
automated
comparisons
fragment,
molecular,
and
crystal
structures
have
become
possible.
They
show
that
distributions
interatomic
distances,
angles,
torsion
angles
for
a
given
structural
fragment
occurring
different
environments
are
highly
correlated
among
themselves
with
other
observables
such
as
spectroscopic
signals,
reaction
activation
energies.
The
correlations
often
extend
continuously
over
large
ranges
parameter
values.
reminiscent
bond
breaking
forming
reactions,
polyhedral
rearrangements,
conformational
changes.
map-qualitatively-the
regions
space
which
molecular
dynamics
take
place,
namely,
low
energy
respective
(free)
surfaces.
extension
continuous
nature
provides
an
organizing
principle
groups
data
suggests
reconsideration
traditional
definitions
descriptions
bonds,
"nonbonded"
"noncovalent"
interactions
terms
Lewis
acids
interacting
bases.
These
aspects
illustrated
selected
examples
historic
importance
some
later
developments.
It
seems
amount
CSD
(and
databases)
knowledge
on
of,
within,
this
body
should
allow
one-in
near
future-to
make
credible
interpolations
possibly
predictions
their
properties
machine
learning
methods.
Chemistry - An Asian Journal,
Год журнала:
2024,
Номер
19(5)
Опубликована: Фев. 23, 2024
Abstract
Halogen
bonds
are
typically
observed
to
have
a
linear
arrangement
with
180°
angle
between
the
nucleophile
and
halogen
bond
acceptor
X−R.
This
linearity
is
commonly
explained
using
σ‐hole
model,
although
there
been
alternative
explanations
involving
exchange
repulsion
forces.
We
employ
two‐dimensional
Distortion/Interaction
Energy
Decomposition
Analysis
examine
archetypal
H
3
N⋯X
2
systems.
Our
results
indicate
that
predominantly
electrostatic,
their
directionality
largely
due
decreased
Pauli
in
configurations
as
opposed
angled
ones
I
Br
As
we
move
smaller
halogens,
Cl
F
,
influence
of
diminishes,
energy
surface
shaped
by
orbital
interactions
electrostatic
These
support
role
forces
influencing
strong
bonds.
Additionally,
demonstrate
2D
useful
tool
for
enhancing
our
understanding
nature
potential
surfaces
noncovalent
interactions.
Abstract
A
taxane
2‐
O
‐benzoyltransferase
(
m
TBT,
derived
from
Accession:
AF297618)
biocatalyzed
the
dearoylation
and
rearoylation
of
next‐generation
precursors
drugs
effective
against
multidrug‐resistant
cancer
cells.
Various
taxanes
bearing
an
acyl,
hydroxyl,
or
oxo
group
at
C13
were
screened
to
assess
their
turnover
by
TBT
catalysis.
The
13‐oxotaxanes
most
productive,
where
‐debenzoylation
13‐oxobaccatin
III
was
turned
over
faster
compared
13‐oxo‐10‐
‐(
n
‐propanoyl)‐10‐
‐deacetylbaccatin
‐(cyclopropane
carbonyl)‐10‐
III,
yielding
~20
mg
each.
catalysis
likely
affected
intramolecular
hydrogen
bond
with
C13−hydroxyl.
Oxidation
13‐oxo
recovered
experimental
data
for
debenzoylation
reaction
supported
Gaussian‐accelerated
molecular
dynamics
simulations
that
evaluated
conformational
changes
caused
different
functional
groups
substrate.
These
findings
also
helped
postulate
‐benzoylation
occurs
on
paclitaxel
pathway
in
nature.
rearoylated
debenzoylated
acceptors
fastest
a
non‐natural
3‐fluorobenzoyl
CoA
among
other
aroyl
thioesters
evaluated,
~10
each
excellent
regioselectivity
laboratory
scale.
Reducing
hydroxyl
yielded
key
modified
baccatin
(~10
scale)
new‐generation
taxoids.
Comptes Rendus Chimie,
Год журнала:
2024,
Номер
27(S2), С. 5 - 19
Опубликована: Март 6, 2024
Nucleophilic
addition
to
carbonyl
groups
is
one
of
the
most
important
reactions
in
organic
synthesis.
In
case
a
prochiral
group,
preference
for
nucleophile
face
π
system
leads
unequal
amounts
two
possible
diastereoisomers.
The
mechanism
this
reaction
various
nucleophiles
(especially
early
main
group
hydride
and
Grignard
reagents)
noncyclic
cyclic
aldehydes
or
ketones
has
fascinated
computational
chemists
nearly
40
years.
This
article
describes
research
that
been
done
on
topic,
incentive
present
author
being
she
started
her
with
topic
returning
it
recent
L'addition
d'un
nucléophile
sur
un
composé
carbonylé
est
une
des
réactions
essentielles
en
synthèse
organique.
Si
le
groupe
carbonyle
prochiral,
l'addition
les
deux
faces
du
système
ne
sont
pas
équivalentes
et
la
réaction
conduit
à
excès
diastéréoisomères.
Le
mécanisme
de
ces
pour
divers
nucléophiles
(hydrures
éléments
principal
réactifs
type
particulier)
aldéhydes
ou
cétones
cycliques
non
attiré
l'attention
nombreux
théoriciens
depuis
pratiquement
ans.
Cet
décrit
l'historique
recherches
dans
ce
domaine.
L'auteure
s'est
intéressée
sujet
car
elle
entrée
recherche
avec
domaine
y
revenue
toutes
dernières
années.
Chemical Science,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 23, 2024
A
general,
efficient
and
flexible
approach
based
on
fragmentation
ONIOM-type
boundary
strategies
aids
computational
experimental
chemists
in
visualizing
distortion
maps
evaluating
the
local
energy
of
various
molecules.