Ju-Feng Sun

Synthesis, structure and luminescence of Co-crystals with hexagonal channels: arranging disposition and π–π interactions

Co-crystallization of asymmetric building blocks 5-(4-pyridyl)pyrimidine (A) and 5-(4-(1-imidazolyl)phenyl)pyrimidine (B) with resorcinol and hydroquinone, respectively, was investigated. Four new organic co-crystals (1–4) were generated. The X-ray single crystal analysis indicates that the crystal packing in 1, 2 and 4 generates open hexagonal channels with resorcinol or hydroquinone molecules encapsulated through hydrogen bonding interactions. In 3, {B2(resorcinol)2} macrocycle is generated from clip-like resorcinol and asymmetric B molecules. In addition, the luminescent properties of A, B and 1–4 were investigated primarily in the solid state. The luminescent property is dependent on the molecular vertical arranging disposition and the intermolecular π–π contacting characteristic. The results display more interesting tunability of the emission intensity of the building modules by the incorporation of coformers into the co-crystals.

Synthesis, Characterization and Antibacterial Properties of Dihydroxy Quaternary Ammonium Salts with Long Chain Alkyl Bromides

Five N‐methyl‐N‐R‐N,N‐bis(2‐hydroxyethyl) ammonium bromides (R = ‐benzyl (chloride, BNQAS), ‐dodecyl (C12QAS), ‐tetradecyl (C14QAS), ‐hexadecyl (C16QAS), ‐octadecyl (C18QAS)) were prepared based on N‐methyldiethanolamine (MDEA) and halohydrocarbon. Five QAS were characterized by FTIR, NMR, and MS. BNQAS, C12QAS, C14QAS, and C16QAS were confirmed by X‐ray single‐crystal diffraction. Their antibacterial properties indicated good antibacterial abilities against E. coli, S. aureus, B. subtilis, especially C12QAS with the best antibacterial ability (100% to E. coli, 95.65% to S. aureus, and 91.41% to B. subtilis). In addition, C12QAS also displayed the best antifungal activities than BNQAS and C18QAS against Cytospora mandshurica, Botryosphaeria ribis, Physalospora piricola, and Glomerella cingulata with the ratio of full marks. The strategy provides a facile way to design and develop new types of antibacterial drugs for application in preventing the fruit rot, especially apple.

Non-toxic O-quaternized chitosan materials with better water solubility and antimicrobial function

Five water-soluble O-quaternary ammonium salt-chitosans (QAS-CS) bearing N-methyl-N-R-N, N-bis(2-hydroxyethyl) ammonium bromides (R=-benzyl (chloride, BNQAS-CS), -dodecyl (C12QAS-CS), -tetradecyl (C14QAS-CS), -hexadecyl (C16QAS-CS), -octadecyl (C18QAS-CS)) were prepared, respectively. They were characterized by FTIR, (1)H NMR and elemental analysis. Through chemical modification of O-quaternized chitosans, the water solubility of all QAS-CS was improved distinctly. Their antibacterial properties indicate good antibacterial abilities against gram-positive bacteria and bad against gram-negative bacteria, therein, C12QAS-CS and C14QAS-CS are the best. More importantly, their cytotoxicity was markedly lower than the corresponding QAS monomers by evaluating for AT2 cell line using CCK-8 assay. The strategy provides a facile way to design and develop new types of antibacterial chitosan materials with better water solubility, better antimicrobial ability and lower cytotoxicity for primary additive agent of self-owned intellectual band-aids.

Design, Synthesis and Bioevaluation of Novel N-Substituted-3,5-Bis(Arylidene)-4-piperidone Derivatives as Cytotoxic and Antitumor Agents with Fluorescent Properties

Ten new N‐substituted‐3,5‐bis(arylidene)‐4‐piperidone derivatives (series 1 and 2) were synthesized and subsequently evaluated against human carcinoma cell lines SW1990, MIA PaCa‐2, PG‐BE1, NCI‐H460, and SK‐BR‐3 for cytotoxic activity by the CCK‐8 method, and their fluorescent properties were investigated as well. The compounds were confirmed to display greater cytotoxic activity to the neoplastic cells, and approximately 50% of the IC50 values were lower than 5 μm. In particular, compounds 1a, 1c, 1d, and 1e bearing 3‐bromophenyl groups were revealed as the most active antitumor drug candidates and had the average IC50 values of 1.94, 1.11, 1.16, and 0.817 μm, respectively. Furthermore, their fluorescent properties were interesting and might contribute to the visualization of their distribution in tumor cells. Some possible reasons for the disparity between cytotoxic activity and fluorescent properties in the two series of compounds were explored. This study revealed high potential of these molecules for further development as fluorescent cytotoxic and antitumor agents.

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

Abstract 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.

New sesquiterpenes from the rhizomes of homalomena occulta.

Six new sesquiterpenes (1-6), along with eight known ones (7-14) were isolated from the rhizomes of Homalomena occulta. Structure elucidation of the new compounds was achieved through 1D NMR, 2D NMR spectroscopic techniques and HRESIMS, while the absolute configurations of compounds 1, 2 and 5 were confirmed by X-ray crystallographic analysis. All of the isolates were evaluated for their activity against LPS-induced production of nitrogen oxide (NO) in macrophage cells, and compounds 1 and 5 showed inhibitory effect on NO production with the IC50 values of 21.2 and 15.4 μM, respectively.

Synthesis, Antiproliferative, and Multidrug Resistance Reversal Activities of Heterocyclic α,β-Unsaturated Carbonyl Compounds.

A series of heterocyclic α,β‐unsaturated carbonyl compounds (1a‐1d, 2a‐2d, 3a‐3d, 4a‐3d, and 5a‐5d) with 1,5‐diaryl‐3‐oxo‐1,4‐pentadienyl pharmacophore were synthesized for the development of anticancer and multidrug resistance reverting agents. The antiproliferative activities were tested against nine human cancer cell lines. Approximately 73% of the IC50 values were below 5 μm, while 35% of these figures were submicromolar, and compounds 3a‐3d with 4‐trifluoro methyl in the arylidene benzene rings were the most potent, since their IC50 values are between 0.06 and 3.09 μm against all cancer cell lines employed. Meanwhile, their multidrug resistance reversal properties and cellular uptake were further examined. The data displayed that all of these compounds could reverse multidrug resistance, particularly, compounds 3a and 4a demonstrated both potent multidrug resistance reverting properties and strong antiproliferative activities, which can be taken as leading molecules for further research of dual effect agents in tumor chemotherapy.

2,6-Di-tert-butyl-4-(methoxy-meth-yl)phenol.

The title compound, C16H26O2, was easily obtained in high yield when 4-bromomethyl-2,6-di-tert-butylphenol was reacted with methanol. There are two independent molecules in the asymmetric unit. The methoxy group in each of the independent molecules was found to be disordered, with site-occupation factors of 0.8728 (18)/0.1272 (18) and 0.8781 (17)/0.1219 (17).

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.

catena-Poly[[bis-(acetato-κO)aqua-copper(II)]-μ-5-(pyridin-3-yl)pyrimidine-κN:N].

In the title compound, [Cu(CH3CO2)2(C9H7N3)(H2O)]n, the CuII ion is pentacoordinated in a square-pyramidal geometry. The N atoms of the two chelating symmetry-related 5-(pyridin-3-yl)pyrimidine ligands and the O atoms of the two monodentate acetate anions are nearly coplanar, with a mean deviation from the least-squares plane of 0.157 (2) Å and the CuII ion is displaced by 0.050 (3) Å from this plane towards the apical water O atom. Bridging through the bis-monodentate 5-(pyridin-3-yl)pyrimidine ligand forms a one-dimensional coordination polymer extending parallel to [010]. In the crystal, O—H⋯O hydrogen bonds link the molecules into a two-dimensional supramolecular structure parallel to (100). The crystal studied was an inversion twin with a 0.57 (3):0.43 (3) domain ratio.