SMINBR: An Integrated Network and Chemoinformatics Tool Specialized for Prediction of Two-Component Crystal Formation

Two-component crystals such as pharmaceutical cocrystals and salts have been proven as an effective strategy to improve physicochemical and biopharmaceutical properties of drugs. It is not easy to select proper molecular combinations to form two-component crystals. The network-based models have been successfully utilized to guide cocrystal design. Yet, the traditional social network-derived methods based on molecular-interaction topology information cannot directly predict interaction partners for new chemical entities (NCEs) that have not been observed to form two-component crystals. Herein, we proposed an effective tool, namely substructure-molecular-interaction network-based recommendation (SMINBR), to prioritize potential interaction partners for NCEs. This in silico tool incorporates network and chemoinformatics methods to bridge the gap between NCEs and known molecular-interaction network. The high performance of 10-fold cross validation and external validation shows the high accuracy and good generalization capability of the model. As a case study, top 10 recommended coformers for apatinib were all experimentally confirmed and a new apatinib cocrystal with paradioxybenzene was obtained. The predictive capability of the model attributes to its accordance with complementary patterns driving the formation of intermolecular interactions. SMINBR could automatically recommend new interaction partners for a target molecule, and would be an effective tool to guide cocrystal design. A free web server for SMINBR is available at http://lmmd.ecust.edu.cn/sminbr/.

Recent advances in persistent luminescence based on molecular hybrid materials

Molecular persistently luminescent materials have received recent attention due to their promising applications in optical displays, biological imaging, chemical sensing, and security systems. In this review, we systematically summarize recent advances in establishing persistently luminescent materials-specifically focusing on materials composed of molecular hybrids for the first time. We describe the main strategies for synthesizing these hybrid materials, namely: (i) inorganics/organics, (ii) organics/organics, and (iii) organics/polymer systems and demonstrate how molecular hybrids provide synergistic effects, while improving luminescence lifetimes and efficiencies. These hybrid materials promote new methods for tuning key physical properties such as singlet-triplet excited state energies by controlling the chemical interactions and molecular orientations in the solid state. We review new advances in these materials from the perspective of examining experimental and theoretical approaches to room-temperature phosphorescence and thermally-activated delayed fluorescence. Finally, this review concludes by summarizing the current challenges and future opportunities for these hybrid materials.

Discovery of novel NF-кB inhibitor based on scaffold hopping: 1,4,5,6,7,8-hexahydropyrido[4,3-d]pyrimidine

NF-κB is a key signaling pathway molecule linking hepatoma and chronic inflammation. Inhibition of NF-κB activation can alleviate inflammation, and promote hepatoma cell apoptosis. In this study, a series of fluoro-substituted 1,4,5,6,7,8-hexahydropyrido[4,3-d]pyrimidines (PPMs, 31-57) were synthesized from 3,5-bis(arylidene)-4-piperidones (BAPs, 4-30) based on scaffold hopping. We successfully discovered the most potent 43 substituted by electron-withdrawing substitutes (3-F and 4-CF₃) exhibited less toxicity and higher anti-inflammatory activity. Preliminary mechanistic studies revealed that 43 induced dose-dependent cell apoptosis at cell and protein level, while inhibited NF-κB activation by suppressing LPS-induced phosphorylation levels of p65, IκBα and Akt, and by indirectly suppressing MAPK signaling, and by inhibiting the nuclear translocation of NF-κB induced by TNF-α or LPS. Docking analysis verified simulated 43 could reasonably bind to the active site of Bcl-2, p65 and p38 proteins. This compound, as a novel NF-κB inhibitor, also demonstrated both anti-inflammatory and anti-hepatoma activities, warranting its further development as a potential multifunctional agent for the clinical treatment of liver cancers and inflammatory diseases.

Crystal structure and anti-inflammatory activity of (3E,5E)-1-((4-chlorophenyl)sulfonyl)-3,5-bis(4-fluorobenzylidene)piperidin-4-one-dichloromethane (1/1), C26H20Cl3F2NO3S

C26H20Cl3F2NO3S, triclinic, P1̄ (no. 2), a = 8.6281(7) Å, b = 11.3695(9) Å, c = 14.3529(11) Å, α = 68.166(7)°, β = 80.707(7)°, γ = 71.169(7)°, V = 1235.65(19) Å3, Z = 2, R gt(F) = 0.0564, wR ref(F 2) = 0.1376, T = 100.00(10) K.

Crystal structure and anti-inflammatory activity of (3E,5E)-3,5-bis(4-fluorobenzylidene)-1-((4-fluorophenyl)sulfonyl)piperidin-4-one-dichloromethane (1/1), C26H20Cl2F3NO3S

C26H20Cl2F3NO3S, triclinic, P1̄ (no. 2), a = 8.5616(4) Å, b = 11.6052(6) Å, c = 14.1451(8) Å, α = 66.617(6)°, β = 82.391(4)°, γ = 69.072(4)°, V = 1204.85(12) Å3, Z = 2, R gt(F) = 0.0460, wR ref(F 2) = 0.1206, T = 100.00(10) K.

Crystal structure and anti-inflammatory activity of (3E,5E)-3,5-bis(2-fluorobenzylidene)-1-((4-fluorophenyl)sulfonyl)piperidin-4-one, C25H18F3NO3S

C25H18F3NO3S, orthorhombic, Pca21 (no. 29), a = 19.1142(7) Å, b = 11.6722(5) Å, c = 9.2390(3) Å, V = 2061.26(13) Å3, Z = 4, R gt(F) = 0.0422, wR ref(F 2) = 0.0974, T = 100.02(10) K.

Characterization, crystal structure and cytotoxic activity of a rare iridoid glycoside from Lonicera saccata

A new iridoid glycoside, methyl (3R,4R,4aS,7S,7aR)-3-hydroxy-7-methyl-5-oxooctahydrocyclopenta[c]pyran-4-carboxylate-3-O-β-D-(1'S,2'R,3'S,4'S,5'R)-glucopyranoside, named loniceroside A, C₁₇H₂₆O₁₀, (1), was obtained from the aerial parts of Lonicera saccata. Its structure was established based on an analysis of spectroscopic data, including 1D NMR, 2D NMR and HRESIMS, and the configurations of the chiral C atoms were determined by X-ray crystallographic analysis. The single-crystal structure reveals that the cyclopenta[c]pyran scaffold is formed from a five-membered ring and a chair-like six-membered ring connected through two bridgehead chiral C atoms. In the solid state, the glucose group of (1) plays an important role in constructing an unusual supramolecular motif. The structure analysis revealed adjacent molecules linked together through intermolecular O-H...O hydrogen bonds to generate a banded structure. Furthermore, the banded structures are linked into a three-dimensional network by interesting hydrogen bonds. Biogenetically, compound (1) carries a glucopyranosyloxy moiety at the C-3 position, representing a rare structural feature for naturally occurring iridoid glycosides. The growth inhibitory effects against human cervical carcinoma cells (Hela), human lung adenocarcinoma cells (A549), human acute mononuclear granulocyte leukaemia (THP-1) and the human liver hepatocellular carcinoma cell line (HepG2) were evaluated by the MTT method.

Crystal structure and anti-inflammatory activity of (3E,5E)-1-((4-chlorophenyl)sulfonyl)-3-(pyridin-4-ylmethylene)-5-(2-(trifluoromethyl)benzylidene)piperidin-4-one, C25H18ClF3N2O3S

C25H18ClF3N2O3S, monoclinic, P21/n (no. 14), a = 9.9087(5) Å, b = 21.7843(10) Å, c = 10.2512(6) Å, β = 94.749(5)°, V = 2205.2(2) Å3, Z = 4, R gt(F) = 0.0448, wR ref(F 2) = 0.1028, T = 100 K.

Crystal structure and anti-inflammatory activity of (3E,5E)-1-((4-bromophenyl)sulfonyl)-3-(pyridin-4-ylmethylene)-5-(2-(trifluoromethyl)benzylidene)piperidin-4-one, C25H18BrF3N2O3S

C25H18BrF3N2O3S, monoclinic, P21/n (no. 14), a = 9.9295(11) Å, b = 21.755(2) Å, c = 10.2358(11) Å, β = 95.022(10)°, V = 2202.6(4) Å3, Z = 4, R gt(F) = 0.0373, wR ref(F 2) = 0.0795, T = 100(1) K.

Crystal structure and anti-inflammatory activity of (3E,5E)-3-(2-fluorobenzylidene)-1-((4-acetamidophenyl)sulfonyl)-5-(pyridin-3-ylmethylene)piperidin-4-one-methanol-hydrate (2/1/1), C53H50F2N6O10S2

C53H50F2N6O10S2, monoclinic, P21/n (no. 14), a = 15.088(5) Å, b = 23.560(9) Å, c = 15.401(6) Å, β = 112.254(5)°, V = 5067(3) Å3, Z = 4, R gt(F) = 0.0509, wR ref(F 2) = 0.1336, T = 298(2) K.

Synthesis, crystal structures and anti-inflammatory activity of fluorine-substituted 1,4,5,6-tetrahydrobenzo[h]quinazolin-2-amine derivatives

Two fluorine-substituted 1,4,5,6-tetrahydrobenzo[h]quinazolin-2-amine (BQA) derivatives, namely 2-amino-4-(2-fluorophenyl)-9-methoxy-1,4,5,6-tetrahydrobenzo[h]quinazolin-3-ium chloride, (8), and 2-amino-4-(4-fluorophenyl)-9-methoxy-1,4,5,6-tetrahydrobenzo[h]quinazolin-3-ium chloride, (9), both C₁₉H₁₉FN₃O⁺·Cl^-, were generated by Michael addition reactions between guanidine hydrochloride and the α,β-unsaturated ketones (E)-2-(2-fluorobenzylidene)-7-methoxy-3,4-dihydronaphthalen-1(2H)-one, C₁₈H₁₅FO₂, (6), and (E)-2-(4-fluorobenzylidene)-7-methoxy-3,4-dihydronaphthalen-1(2H)-one, (7). Because both sides of α,β-unsaturated ketones (6) or (7) can be attacked by guanidine, we obtained a pair of isomers in (8) and (9). Single-crystal X-ray diffraction indicates that each isomer has a chiral C atom and both (8) and (9) crystallize in the achiral space group P2₁/c. The chloride ion, as a hydrogen-bond acceptor, plays an important role in the formation of multiple hydrogen bonds. Thus, adjacent molecules are connected through intermolecular hydrogen bonds to generate a banded structure. Furthermore, these bands are linked into an interesting 3D network via hydrogen bonds and π-π interactions. Fortunately, the solubilities of (8) and (9) were distinctly improved and can exceed 50 mg ml^-1 in water or PBS buffer system (pH 7.4) at room temperature. In addition, the results of an investigation of anti-inflammatory activity show that (8) and (9), with o- and p-fluoro substituents, respectively, display more potential for inhibitory effects on LPS-induced NO secretion than starting ketones (6) and (7).

Crystal structure of (3E,5E)-3,5-bis(4-cyanobenzylidene)-1-((4-fluorophenyl)sulfonyl)piperidin-4-one, C27H18FN3O3S

C27H18FN3O3S, monoclinic, P21/c (no. 14), a = 8.091(6) Å, b = 42.84(3) Å, c = 7.096(6) Å, β = 107.806(10)°, V = 2342(3) Å3, Z = 4, R gt(F) = 0.0616, wR ref(F 2) = 0.1321, T = 173(2) K.

Dissymmetric pyridyl-substituted 3,5-bis(arylidene)-4-piperidones as anti-hepatoma agents by inhibiting NF-κB pathway activation

To get new anti-hepatoma agents with anti-inflammatory activity and hypotoxicity, a series of dissymmetric pyridyl-substituted 3,5-bis(arylidene)-4-piperidones (BAPs, 25-82) were designed and synthesized. Many of them exhibited potential anti-hepatoma properties against human hepatocellular carcinoma cell lines (HepG2, QGY-7703, SMMC-7721) and hypotoxicity for human normal heptical cell line (HHL-5, LO2), and prominently inhibited lipopolysaccharides (LPS) induced IL-6, TNF-α secretion to exert its anti-inflammatory effect. Combining the data of cytotoxicity, cytocompatibility and anti-inflammatory activity, 3-pyridyl and -CF₃ substituted 67 may be the potential anti-hepatoma agent. 67 effectively promoted cell apoptosis through up-regulating cleaved caspase-3 and Bax expression and down-regulating Bcl-2 expression. Furthermore, 67 prominently inhibited NF-κB pathway activation by blocking the phosphorylation of IκBα, p65 and the nuclear translocation of NF-κB induced by TNF-α and LPS. In addition, 67 could reasonably bind to the active site of Bcl-2 and NF-κB/p65 protein proved by Molecular docking analyses. Moreover, 67 significantly suppressed the growth and inflammatory response of HepG2 xenografts in nude mice and was relatively nontoxic to mice. These results suggest that 67 may be effective and hypotoxicity anti-hepatoma agent for the clinical treatment of liver cancers.

Synthesis, crystal structures and anti-inflammatory activity of four 3,5-bis(arylidene)-N-benzenesulfonyl-4-piperidone derivatives

3,5-Bis(arylidene)-4-piperidone (BAP) derivatives display good antitumour and anti-inflammatory activities because of their double α,β-unsaturated ketone structural characteristics. If N-benzenesulfonyl substituents are introduced into BAPs, the configuration of the BAPs would change significantly and their anti-inflammatory activities should improve. Four N-benzenesulfonyl BAPs, namely (3E,5E)-1-(4-methylbenzenesulfonyl)-3,5-bis[4-(trifluoromethyl)benzylidene]piperidin-4-one dichloromethane monosolvate, C₂₈H₂₁F₆NO₃S·CH₂Cl₂, (4), (3E,5E)-1-(4-fluorobenzenesulfonyl)-3,5-bis[4-(trifluoromethyl)benzylidene]piperidin-4-one, C₂₇H₁₈F₇NO₃S, (5), (3E,5E)-1-(4-nitrobenzenesulfonyl)-3,5-bis[4-(trifluoromethyl)benzylidene]piperidin-4-one, C₂₇H₁₈F₆N₂O₅S, (6), and (3E,5E)-1-(4-cyanobenzenesulfonyl)-3,5-bis[4-(trifluoromethyl)benzylidene]piperidin-4-one dichloromethane monosolvate, C₂₈H₁₈F₆N₂O₃S·CH₂Cl₂, (7), were prepared by Claisen-Schmidt condensation and N-sulfonylation. They were characterized by NMR, FT-IR and HRMS (high resolution mass spectrometry). Single-crystal structure analysis reveals that the two 4-(trifluoromethyl)phenyl rings on both sides of the piperidone ring in (4)-(7) adopt an E stereochemistry of the olefinic double bonds. Molecules of both (4) and (6) are connected by hydrogen bonds into one-dimensional chains. In (5) and (7), pairs of adjacent molecules embrace through intermolecular hydrogen bonds to form a bimolecular combination, which are further extended into a two-dimensional sheet. The anti-inflammatory activity data reveal that (4)-(7) significantly inhibit LPS-induced interleukin (IL-6) and tumour necrosis factor (TNF-α) secretion. Most importantly, (6) and (7), with strong electron-withdrawing substituents, display more potential inhibitory effects than (4) and (5).

Crystal structure of 4-((E)-((E)-5-(2-fluorobenzylidene)-1-((4-fluorophenyl)sulfonyl)-4-oxopiperidin-3-ylidene)methyl)benzonitrile, C26H18F2N2O3S

C26H18F2N2O3S, monoclinic, P21/c (no. 14), a = 8.412(3) Å, b = 22.056(8) Å, c = 12.125(4) Å, β = 102.316(5)°, V = 2198.0(14) Å3, Z = 4, R gt(F) = 0.0475, wR ref(F 2) = 0.1156, T = 173(2) K.

Quaternary ammonium salts substituted by 5-phenyl-1,3,4-oxadiazole-2-thiol as novel antibacterial agents with low cytotoxicity

Twenty-one novel 5-phenyl-1,3,4-oxadiazole-2-thiol (POT) substituted N-hydroxyethyl quaternary ammonium salts (6a-g, 7a-g, 8a-g) were prepared and characterized by FTIR, NMR, and elemental analysis. Compounds 6a, 6c, and 8a were confirmed by X-ray single-crystal diffraction. They display the unsurpassed antibacterial activity against Staphylococcus aureus, α-H-tococcus, Escherichia coli, P. aeruginosa, Proteus vulgaris, Canidia Albicans, especially 6g, 7g, 8g with dodecyl group. Compounds 8a-d with N,N-dihydroxyethyl and POT groups display unsurpassed antibacterial activity and non-toxicity. The structure-activity relationships indicate that POT and flexible dihydroxyethyl group in QAS are necessary for antibacterial activity and cytotoxicity. SEM and TEM images of E. coli morphologies of 8d show the antibacterial agents can adhere to membrane surfaces to inhibit bacterial growth by disrupting peptidoglycan formation and releasing bacterial cytoplasm from cell membranes.

Synthesis, antitumor activity evaluation of some new N-aroyl-α,β-unsaturated piperidones with fluorescence

Novel N-aroyl-α,β-unsaturated piperidones, series 1, series 2 and series 3 (featuring 2-bromo-4,5-dimethoxybenzylidene, 4-dimethylaminobenzylidene and 4-trifluoromethylbenzylidene, respectively), were synthesized as candidate cytotoxins. Most of the compounds displayed potent cytotoxicity against the human neoplastic cell lines SK-BR-3, PG-BE1, NCI-H460, MIA PaCa-2 and SW1990 in vitro, and approximately 64% of the IC50 values were lower than 5 μM. Among those tested, compound 1b of series 1, 3a, 3d and 3e of series 3 proved to be the most active. Importantly, 1b displayed marked inhibitory effects on tumor growth in vivo and had no apparent toxicity to mice; this was evaluated by a nude mouse PG-BE1 xenograft model. In addition, the fluorescent properties of compounds series 1-3 were investigated. The interesting fluorescence exhibited by these compounds could be useful for their visualization in tumor cells, permitting further studies on these α,β-unsaturated piperidones as candidates for novel fluorescent antitumor agents.

Influence of N-heteroaromatic π–π stacking on supramolecular assembly and coordination geometry; effect of a single-atom change in the ligand

A study on how the polarization of aromatic systems, through the introduction of a nitrogen heteroatom, affects the π–π interactions and crystal packing of mercury coordination compounds.