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Sixteen substituted 1-hydroxy-3-methylxanthones were synthesized in one step. The yields ranged from 33 to 76%. Then, the antitumor, antioxidant, anti-tyrosinase, anti-pancreatic lipase, and antifungal activities of compounds 1–16 were evaluated. Compounds 10–12 and 14 inhibited tyrosinase and pancreatic lipase activity to a certain extent, respectively. Compound 16 exhibited obvious cytotoxicity against fifteen cancer cells, moderate antioxidant activity, and moderate inhibitory activity against Candida albicans. In particular, compound 16 exhibited strong inhibitory activity against A-549 and A549/Taxol cells. These results demonstrated that compounds 10–12, 14, and 16 are promising leads for further structural modification. [ABSTRACT FROM AUTHOR]

Self-assembly of rod-coil-rod ABA triblock copolymers in a rod-selective solvent is investigated by using dissipative particle dynamics simulations. The morphologies of the self-assembled aggregates are dependent on the number of copolymers in the aggregate and the rod length of the copolymer. We observe vesicles at short rod block and bowl-like aggregates at slightly longer rod block. In the vesicle region near the phase boundary, metastable bowl-like aggregates can be observed and be transformed into vesicles by annealing process. A transition from the bowl-like structure to the vesicle is observed by increasing the solvophobicity of the mid-coil block. In this study, the difference between the self-assembly of fully flexible ABA triblock copolymer and that of rod-coil-rod triblock copolymer is also discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Extraction and subsequent E can release many SSs from HSBC and IEP. • The predominant CS in HSBC and its R s are aliphatic and aromatic carbons. • The main oxygen occurrence are >C-OH and >C-O- moieties in HSBC and its R s. • R S , especially R IEP , can be further used in pyrolysis or porous material precursors. The structural features (SFs) of Hecaogou subbituminous coal (HSBC) and its residues (R s) were investigated with non-destructive tools, including scanning electron microscope (SEM), solid-state 13C nuclear magnetic resonance (SS 13C NMR), Fourier transform infrared spectrometer (FTIRS), and X-ray photoelectron spectrometer (XRPES), combined with thermogravimetric analyzer (TGA) and flash pyrolysis (FP). SS 13C NMR analysis shows that both HSBC and its R s consist of aliphatic, aromatic, and carbonyl carbon species. The total content of aliphatic carbon species in the R s is lower than that in HSBC, but the content of carbonyl carbon species is basically unchanged. In both HSBC and its R s, aliphatic linkages connect 3–5 aromatic rings (ARs) and the number of substituents on each AR is up to 2 on average. Based on the semi-quantitative analysis with FTIRS and TGA, cleavaging weak- and medium-strength covalent bonds (>C al -X-, X denotes H, N, S, or >C al) should be the main reactions during the ethanolysis of HSBC and its inextractable portion. The analysis with XRPES indicates that the main oxygen-, nitrogen-, and sulfur-containing moieties are >C-O- groups, pyrrolic, and aromatic and sulfonic sulfurs, respectively, on the surface of HSBC and its R s. Considerable amounts of alkanes and alkenes were released and non-substituted arenes are the main arenes released from the FP of HSBC and its R s. [ABSTRACT FROM AUTHOR]

Dissipativeparticle dynamics simulations are performed to investigatethe self-assembly of rod–coil diblock copolymers RNRCN–NRwithin a rod-selective slit. The self-assembled structureof the confined system is sensitively dependent on the rigidity kθand the fraction fRof the rod block and the slit height H.From the phase diagram of structures with respect to kθand fRfor N= 12 and H= 6, we observe four mainstructures including disordered cylinder (DC) structure, hexagonallypacked cylinders (HPC) perpendicular to the slit surfaces, and lamellarstructures parallel (L∥) and perpendicular (L⊥) to surfaces. And structure transitions can be achievedby tuning kθ. The effect of theslit height on the self-assembled structure is also studied for R6C6and R7C5copolymers withlarge kθ. For R6C6, different structures near surfaces and in the interior ofslit are observed in relatively wide slits. Whereas for R7C5, L⊥structure, whose lamellar domainspacing decays exponentially with H, is generallygenerated. Our results suggest an effective way to control the orderingof rod–coil diblock copolymers under nanoscale confinement. [ABSTRACT FROM AUTHOR]