N
-((4-Bromophenyl)(2-hydroxynaphthalen-1-yl)methyl)acetamide (BHMA) is a 1-amidoalkyl-2-naphthol derivative that has been reported to exhibit good acetylcholinesterase and α-glycosidase inhibitory ...activities. In the present paper, the free radical scavenging activity and mechanisms of BHMA were investigated using in vitro methods and quantum chemistry calculations. The molecular geometry of BHMA was first established using single-crystal X-ray diffraction analysis and was found to be nearly identical to that obtained theoretically. Then, the free radical scavenging activity of BHMA was evaluated by a series of in vitro assays including ABTS, phenanthroline and CUPRAC. After that, DFT (density functional theory)-based computational methods were used to study the main antioxidant mechanisms for all the possible sites of BHMA. As a result, BHMA was found to be a potent free radical scavenger with activity comparable to that of BHT and BHA. The OH bond was predicted to be more active for trapping free radicals than the NH/CH bonds. Hydrogen atom transfer and sequential proton loss electron transfer are, respectively, the dominant mechanisms in the gas phase and ethanol.
The title compound, C
H
N
OF, is a member of the azo dye family. The dihedral angle subtended by the benzene ring and the naphthalene ring system measures 18.75 (7)°, indicating that the compound is ...not perfectly planar. An intra-molecular N-H⋯O hydrogen bond occurs between the imino and carbonyl groups. In the crystal, the mol-ecules are linked into inversion dimers by C-H⋯O inter-actions. Aromatic π-π stacking between the naphthalene ring systems lead to the formation of chains along 001. A Hirshfeld surface analysis was undertaken to investigate and qu-antify the inter-molecular inter-actions. In addition, energy frameworks were used to examine the cooperative effect of these inter-molecular inter-actions across the crystal, showing dispersion energy to be the most influential factor in the crystal organization of the compound.
The title compound, C
17
H
13
NO
3
, adopts a
Z
configuration about the C=C bond. The isoxazole and methoxybenzylidene rings are almost coplanar with a dihedral angle of 9.63 (7)° between them. In ...contrast, the phenyl substituent is twisted significantly out of the plane of the oxazole ring, with the two rings inclined to each other by 46.22 (4)°. The crystal structure features C—H...O, C—H...N and C—H...π hydrogen bonds and π–π contacts. An analysis of the Hirshfeld surfaces points to the importance of H...H, H...C/C...H and H...O/O...H contacts. The included surface areas of the title compound were compared to those of the isomeric structure (
Z
)-4-(4-methoxybenzylidene)-3-phenylisoxazol-5(4
H
)-one Zhang
et al.
(2015).
CrystEngComm
,
17
, 7316–7322.
The title compound, C
8
H
8
O
2
S
2
, contains a cyclohexane-1,3-dione ring, which has a twist-boat conformation. The C
2
S
2
ring is close to planar (r.m.s. deviation = 0.023 Å) and the dihedral ...angle between the mean planes of the cyclohexane and 1,3-dithietane rings is 9.1 (3)°. Short intramolecular S...O contacts occur 2.719 (5) and 2.740 (5) Å. In the crystal, the molecules are linked by weak C—H...S hydrogen bonds and short 3.165 (5) Å S...O contacts, forming (010) layers. The prevalence of these interactions is illustrated by an analysis of the three-dimensional Hirshfeld surface and by two-dimensional fingerprint plots.
The title compound, C
H
NO
S crystallizes with two independent mol-ecules (
and
) in the asymmetric unit with
= 8. Both mol-ecules are almost planar with a dihedral angle between the isoxazole and ...thio-phen rings of 3.67 (2)° in mol-ecule
and 10.00 (1) ° in mol-ecule
. The packing of mol-ecules
and
is of an
type along the
-axis direction, the configuration about the C=C bond is
. In the crystal, the presence of C-H⋯O, C-H⋯ N and π-π inter-actions centroid-centroid distances of 3.701 (2) and 3.766 (2) Å link the mol-ecules into a three-dimensional architecture. An analysis of Hirshfeld surfaces shows the importance of C-H⋯O and C-H⋯N hydrogen bonds in the packing mechanism of the crystalline structure.
The title compounds, 2,6-diiodo-4-nitrotoluene (DINT, C
7
H
5
I
2
NO
2
) and 2,4,6-tribromotoluene (TBT, C
7
H
5
Br
3
,), are trisubstituted toluene molecules. Both molecules are planar, only the H ...atoms of the methyl group, and the nitro group in DINT, deviate significantly from the plane of the benzene ring. In the crystals of both compounds, molecules stack in columns up the shortest crystallographic axis,
viz
. the
a
axis in DINT and the
b
axis in TBT. In the crystal of DINT, molecules are linked
via
short N—O...I contacts, forming chains along 100. In TBT, molecules are linked by C—H...Br hydrogen bonds, forming chains along 010. Hirshfeld surface analysis was used to explore the intermolecular contacts in the crystals of both DINT and TBT.
In the title compound, C
30
H
20
Cl
2
O
2
Se, the C—Se—C angle is 99.0 (2)°, with the dihedral angle between the planes of the attached benzene rings being 79.1 (3)°. The average endocyclic angles ...(Se—C—C) facing the Se atom are 122.1 (5) and 122.2 (5)°. The Se atom is essentially coplanar with the attached benzene rings, deviating by 0.075 (1) and 0.091 (1) Å. In the two phenylene(4-chlorophenyl)prop-2-en-1-one units, the benzene rings are inclined to each other by 44.6 (3) and 7.8 (3)°. In the crystal, the molecules stack up the
a
axis, forming layers parallel to the
ac
plane. There are no significant classical intermolecular interactions present. Hirshfeld surface analysis, two-dimensional fingerprint plots and the molecular electrostatic potential surface were used to analyse the crystal packing. The Hirshfeld surface analysis suggests that the most significant contributions to the crystal packing are by C...H/H...C contacts (17.7%).
The title compound, C
H
NO
, is of inter-est as a precursor to biologically active substituted quinolines and related compounds. This compound crystallizes with two independent mol-ecules (
and
) in ...the asymmetric unit. The dihedral angles between mean planes of the methyl-phenyl ring and the naphthalene ring system are 78.32 (6) and 84.70 (6)° in mol-ecules
and
, respectively. In the crystal, the anti-ferroelectric packing of mol-ecules
and
is of an
type along the
-axis direction. The crystal structure features N-H⋯O, O-H⋯O and weak C-H⋯O hydrogen bonds, which link the mol-ecules into infinite chains propagating along the
-axis direction.
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