Structural control, and especially chirality control, remains a significant challenge in the synthesis of single-walled carbon nanotubes (SWNTs). We report herein a rational approach to engineering fullerene caps for growing SWNTs with controlled structures via chemical vapor deposition (CVD). Opening of fullerendione via thermal oxidation yields hemispherical caps which can initiate SWNT growth at their open ends. The size and structure of these caps can be engineered by tuning the temperature of thermal oxidation. Results show that pregrowth treatment of the cap is indispensable to successful growth of SWNTs. The temperature used for thermal oxidation strongly affects the size and structure of the cap and further determines the diameter distribution of the as-grown SWNTs. Stronger oxidation treatments (450 degrees C oxidation in air) promote formation of thinner SWNTs, while weaker oxidation treatments (350 degrees C oxidation in air) lead to wider SWNTs. Interestingly, SWNTs made using fullerene caps show steplike diameter distributions relative to SWNTs catalyzed by Fe nanoparticles. This cap engineering using opened C(60) provides a potential approach to grow SWNTs with controlled structures.

A series of 5-keto-substituted 7-tert-buty1-2,3-dihydro-3,3- dimethylbenzofurans (DHDMBFs) were prepared and evaluated as potential nonsteroidal antiinflammatory and analgesic agents. Interest in this class of compounds arose when a DHDMBF was found to be an active metabolite of the di-tert-butylphenol antiinflammatory agent tebufelone. We have now found that a variety of 5-keto-substituted DHDMBFs have good in vivo antiinflammatory and analgesic activity after oral administration. These compounds inhibit both cyclooxygenase (COX) and 5-lipoxygenase (5-LOX) in vitro. The cyclooxygenase inhibition was found to be selective for the cyclooxygenase-2 isoform, and this combination of COX-2/5-LOX inhibition may be responsible for the gastrointestinal safety of compounds such as 30.

The aim of this review is to explore the fundamental and technological incentive for the molecular design, synthesis, and aggregation behavior of conjugated organic molecules with photo‐electronic activity, and the fabrication of low‐dimensional organic conjugated nanomaterials by self‐assembly techniques. The properties of large oriented nanostructure arrays of organic charge transfer complexes based on conjugated molecules are also discussed. The dimension‐dependent emission properties have been observed, and conductivity, field emission properties, and sensing properties have been studied for the low dimensional nanostructures of nanoparticles, nanowires, nanorods, and nanostructure arrays.

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Biocompatible, biodegradable, and luminescent nano material can be used as an alternative bioimaging agent for early cancer diagnosis, which is crucial to achieve successful treatment. Hydroxyapatite (HAP) nanocyrstals have good biocompatibility and biodegradability, and can be used as an excellent host for luminescent rare earth elements. In this study, based on the energy transfer from Gd(3+) to Eu(3+), the luminescence enhanced imaging agent of Eu/Gd codoping HAP (HAP:Eu/Gd) nanocrystals are obtained via coprecipitation with plate-like shape and no change in crystal phase composition. The luminescence can be much elevated (up to about 120%) with a nonlinear increase versus Gd doping content, which is due to the energy transfer ((6)PJ of Gd(3+) → (5)HJ of Eu(3+)) under 273 nm and the possible combination effect of the cooperative upconversion and the successive energy transfer under 394 nm, respectively. Results demonstrate that the biocompatible HAP:Eu/Gd nanocrystals can successfully perform cell labeling and in vivo imaging. The intracellular HAP:Eu/Gd nanocrystals display good biodegradability with a cumulative degradation of about 65% after 72 h. This biocompatible, biodegradable, and luminescence enhanced HAP:Eu/Gd nanocrystal has the potential to act as a fluorescent imaging agent in vitro and in vivo.

Direct cross-coupling to construct sp3 C-sp3 C bonds via Fe-catalyzed benzylic C-H activation with 1-aryl vinyl acetate was developed.

We report an expansion of the scope of our initial discovery that 5-keto-substituted 7-tert-butyl-2,3-dihydro-3,3-dimethylbenzofurans (DHDMBFs) are antiinflammatory and analgesic agents. Several other functional groups have been introduced at the 5 position: amides, amidines, ureas, guanidines, amines, heterocycles, heteroaromatics, and heteroaryl ethenyl substituents in the 5 position all provide active compounds. These compounds are dual cyclooxygenase (COX) and 5-lipoxygenase (5-LOX) inhibitors. They inhibit both COX-1 and COX-2 with up to 33-fold selectivity for COX-2.

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