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Reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization-induced self-assembly (PISA) was conducted in the presence of poly(methyl methacrylate) (PMMA) stabilizer in ethanol/water mixture (80/20 by volume). Two different systems were explored by utilizing (i) 2-ethylhexyl methacrylate (EHMA) and (ii) n -butyl methacrylate (BMA). The morphology transitions of these systems were investigated by varying the polymerization conditions, i.e., the presence of the solvophilic comonomer MMA, the solids content, and the target degree of polymerization (DP). As observed in conventional PISA, the presence of solvophilic comonomer, increase in solids content and target DP promoted the formation of high-order morphology. However, unusual morphology transitions were observed whereby the morphology transformed from high-order morphologies to a mixture of spherical nanoparticles, worms, and vesicles and finally to vesicles with increasing target DP. This unusual evolution may be attributed to the limited solubility of PMMA in the ethanol/water solvent mixture, whereby PMMA is soluble at the polymerization temperature but insoluble at lower temperatures.

The mechanism of sediment formation during the storage of green tea beverage was investigated. Green tea extract was separated by Diaion HP-20 column chromatography, and a sediment-formation test was performed. Results showed that at least one compound of the substance causing flock sediment was contained in each of the HP-20 nonadsorbed and adsorbed fractions. From the following fractionations and structure analyses, the substance in the HP-20 adsorbed fraction was determined to be 1-O-galloyl-4,6-O-(S)-hexahydroxydiphenoyl-beta-D-glucose (strictinin), which is one of the ellagitannins. Strictinin was hydrolyzed to ellagic acid by heat-sterilization processes such as retort sterilization or the ultra-high temperature processing used during the manufacturing of tea beverages. Ellagic acid combined with proteins in the HP-20 nonadsorbed fraction to form an irreversible sediment of green tea beverage; ellagic acid and proteins were confirmed to be present in that sediment. The HP-20 adsorbed fraction contained little strictinin and formed hardly any sediment, suggesting that control of the strictinin content is significant in avoiding sediment formation during the manufacturing process of tea beverages.

To generate dibenzotetrakisdehydro[12]- and dibenzopentakisdehydro[14]annulenes ([12]- and [14]DBAs) having a highly deformed triyne moiety, [4.3.2]propellatriene-anneleted dehydro[12]- and dehydro[14]annulenes were prepared as their precursors. UV irradiation of the precursors resulted in the photochemical [2 + 2] cycloreversion to generate the strained [12]- and [14]DBAs, respectively. The [12]DBA was not detected by 1H NMR spectroscopy, but it was intercepted as Diels-Alder adducts in solution, suggesting its intermediacy. Its spectroscopic characterization was successfully carried out by UV-vis spectroscopy in a 2-methyltetrahydrofuran (MTHF) glass matrix at 77 K and by FT-IR spectroscopy in an argon matrix at 20 K. On the other hand, the [14]DBA was stable enough for observation by 1H and 13C NMR spectra in solution, though it was not isolated because of the low efficiency of the cycloreversion. The [14]DBA was also characterized by interception as Diels-Alder adducts in solution and by UV-vis spectroscopy in a MTHF glass matrix at 77 K. The kinetic stabilities of the DBAs are compared with the related dehydrobenzoannulenes with respect to the topology of the pi-systems. In addition, the tropicity of the [14]DBA is discussed based on its experimental and theoretical 1H NMR chemical shifts.

A novel approach in the fabrication of microarrays of dye and protein on fused silica plates using the laser-induced backside wet etching (LIBWE) technique is described. The surface of fused silica plates was initially precoated using trimethoxysilane self-assembled monolayers (SAMs) and then etched using the LIBWE method to obtain the desired microstructures on the plate surface. Using this technique, the SAMs on the nonirradiated areas were able to survive the LIBWE process and were used as templates for the subsequent deposition of dye molecules or proteins via chemical bonding or physical adsorption. In the case of fused silica plates precoated with fluorinated SAMs, the LIBWE method is used to remove the SAMs to expose the etched silica surfaces, on which a thin layer of pyranine molecules can be site-selectively deposited using an aqueous solution of pyranine. In another application, an ethanol solution of rhodamine 6G was preferentially deposited onto the nonirradiated areas. In yet another application, bovine serum albumin was preferentially deposited onto the laser-irradiated areas; in this case, the fused silica plates were precoated with poly(ethylene oxide) SAMs. Interestingly, when an aqueous suspension of polystyrene (PS) microbeads was cast onto the fused silica precoated with the fluorinated SAMs, hexagonally close-packed PS microbeads were deposited into the etched cavities. Depositions of the dye, protein, and microbeads were confirmed by visualization using a fluorescence microscope and scanning electron microscope.

We have studied the matrix photolysis of 2,4,6-triazido-1,3,5-triazine (cyanuric triazide, 1). Stepwise generation of the corresponding mononitrene, dinitrene, and trinitrene was observed by matrix IR and electron paramagnetic resonance (EPR) spectroscopy. The generated species were identified by comparison of their matrix IR spectra with density functional theory (DFT) computational results. The generation of 2,4,6-trinitreno-1,3,5-triazine with a septet ground state was confirmed for the first time by matrix EPR spectroscopy. The trinitrene readily decomposed into three NCN molecules upon further photoirradiation. This process was also confirmed by matrix EPR spectroscopy.

In the chemistry toward generating benzdiyne from five benzenetetracarboxylic dianhydride derivatives, ketene formation was exclusively observed in the photolysis of difluorobenzenetetracarboxylic dianhydride in a nitrogen matrix at 13 K. Two ketenes were formed concomitantly with difluorobenzdiyne. These ketenes were identified on the basis of good agreement between the observed and calculated (B3LYP/6-31G level) IR spectra. Neither ketene contained the five-membered-ring moiety as cyclopentadienylideneketene, which is formed by Wolff rearrangement in the benzyne chemistry. The first generated ketene was assigned to a ketene with a cyclopropene moiety, and the second, to a ketene with a butadiyne moiety. The first generated ketene was a major product in the photolysis and was formed by cleavage of the bond connecting the ketene group and the C-F carbon and not the bond connecting the ketene group and the carbene moiety. Thus the structures of these ketenes indicated that a unprecedented ring cleavage, rather than Wolff rearrangement, is the dominant process in the benzdiyne chemistry.

We report here the generation of tetrakisdehydro[12]annulene possessing a highly deformed triyne component from the [4.3.2]propellatriene-annelated precursor by its photolysis extruding indan and the characterization of the highly reactive annulene by chemical and spectroscopic methods. In addition to the chemical evidence for the formation of the title compound in solution such as interception as a Diels-Alder adduct, we succeeded in its characterization by UV-vis and FTIR spectra in an argon matrix at 20 K. The experimental IR spectrum agreed well with the theoretical one calculated by the DFT method.

Toward direct observation of benzdiynes, we investigated the wavelength-selective photolyses of five kinds of benzenetetracarboxylic dianhydride derivatives in nitrogen matrixes at 13 K. In the first step of the photolyses, all dianhydrides were converted into benzynedicarboxylic anhydrides with loss of CO and CO2 upon irradiation at 308 nm. In the second step, the benzyne intermediates were photolyzed at 266 nm. In these photolyses, the generation of two kinds of benzdiynes, 3,6-difluoro-1,4-benzdiyne and 3,6-bis(trifluoromethyl)-1,4-benzdiyne, was confirmed by good correspondence between observed and calculated IR spectra. These benzdiynes were converted into the corresponding hexatriynes upon further irradiation at 266 nm. Benzdiynes were not observed in the photolyses of the other three dianhydrides: only hexatriynes were observed as major photoproducts. These results suggested that benzdiynes were generated first and then converted into hexatriynes and that the efficiency of the decomposition of benzdiynes depended on the substituents. The dynamics of the generation and decomposition of benzdiynes in the matrixes was analyzed by using a successive reaction scheme.

A series of compounds, which are analogues of 2,2'-dithiobis(benzamide), were synthesized and tested for in vitro antibacterial activity against Mycobacterium tuberculosis H37Rv including resistant strains against streptomycin, kanamycin, or isonicotinic acid hydrazide. MICs of these compounds against atypical mycobacteria, Mycobacterium kansasii and Mycobacterium intracellulare were also examined. Structure-activity relationships were found in a series of (acyloxy)alkyl ester derivatives depending upon the length of alkyl carbon chain. The MIC of the most potent compound, 2,2'-dithiobis[N-[3-(decanoyloxy)propyl]benzamide] [56] was superior or at least equivalent to streptomycin, kanamycin, and ethanbutol. All the compounds showed no cross-resistance between the current antitubercular agents.