I present herein the development of highly active and reusable polymeric catalysts produced by self-assembly process of non-cross-linked amphiphilic polymeric ligands with inorganic species. Thus, PWAA 1 prepared from H₃PW₁₂O₄₀ and poly[(N-isopropylacrylamide)-co-(acrylamide with ammonium salt)] is suitable for oxidation of alcohols, amines, and sulfides in aqueous hydrogen peroxide. PdAS 2 produced by self-organization of (NH₄)₂PdCl₄ and poly[(N-isopropylacrylamide)₁₀-co-diphenylphosphinostyrene] is an excellent recyclable catalyst for Suzuki–Miyaura reaction in water, water-organic solvent, and organic solvent. It is commercially available from Tokyo Kasei Kogyo (TCI). PdAS-V 3 assembled from (NH₄)₂PdCl₄ and poly[(N-isopropylacrylamide)₅-co-diphenylphosphinostyrene] provides recycling system of itself for Mizorogi–Heck reaction. TiSS 4 made from Ti(O-i-Pr)₄ and poly(styryl-linked binaphtholate-co-styrene) promotes an enantioselective carbonyl-ene reaction as a recyclable catalyst.

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Crude extracts of callus and roots of Dipteryx odorata were analyzed by HPLC to detect and quantify isoflavone contents. Based on spectroscopic and X-ray crystallography data the structures of two isoflavones were elucidated as 7-hydroxy-4′,6-dimethoxyisoflavone and 3′,7-dihydroxy-4′,6-dimethoxyisoflavone. The production of dry biomass of 7-hydroxy-4′,6-dimethoxyisoflavone in cultured callus was 4.12 mg/g, approximately eleven fold higher than the amount accumulated in roots of D. odorata wild-growing plants. The 7-hydroxy-4′,6-dimethoxyisoflavone was effective against glyceraldehyde-3-phosphate dehydrogenase from Trypanosoma cruzi. This is the first report on those bioactive isoflavones accumulated in callus of D. odorata.

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An efficient and highly stereoselective total synthesis of d-biotin has been achieved starting from cis-1,3-dibenzyl-2-imidazolidone-4,5-dicarboxylic acid (2) with an overall yield of 33%. Polymer-supported oxazaborolidine-catalyzed asymmetric reduction of meso-cyclic imide 4 constitutes the key synthetic step in introducing stereogenic centers into the d-biotin molecule.

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This study reports the potent inhibitory effect of N-aryl S-alkylthiocarbamate derivatives on mushroom tyrosinase (MT) activity. N-Aryl S-alkylthiocarbamate derivatives were found to exhibit a potent inhibitory effect on the dopa (3,4-dihydroxyphenylalanine) oxidase activity of mushroom tyrosinase. Most of the N-aryl S-alkylthiocarbamate derivatives (compounds from A to J) exhibited higher inhibitory effects than kojic acid (IC₅₀=318 μm), a well known tyrosinase inhibitor. Tyrosinase was the most inhibited by S-phenetyl N-phenylthiocarbamate (compound E, IC₅₀=7.25 μM), and this inhibition was 44 times stronger than that of kojic acid. Compound E exhibited 95.0% of inhibition at 100 μM. A kinetic study of MT inhibition by compound E using the Lineweaver–Burk plots analysis was performed. And the kinetics profiles observed suggest that compound E competitively inhibits MT.

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To improve the fluorescence characteristics, especially emission wavelength, of coumarins, various 3-substituted-6-methoxycoumarin derivatives were synthesized, and then benzocoumarin derivatives were also synthesized in expectation of the shift to the longer wavelength region by the extension of the conjugated system. Their fluorescence properties were investigated spectrophotometrically in acetonitrile and evaluated from the viewpoint of the intramolecular charge transfer (ICT) between push- and pull-substituents in the ground and the excited states. Among them, benzocoumarin derivatives especially fluoresced in the longer wavelength around 540 nm with remarkably large Stokes shifts beyond 10000 cm⁻¹. Using such fluorophores, some novel fluorescence derivatization reagents for carboxylic acids, alcohols, phenols, and amines were preliminarily prepared as an example, and their derivatized products were also found to fluoresce in the longer wavelength region with large Stokes shifts.

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A powder solid dispersion system (SD) of indomethacin (IM) with crospovidone (CrosPVP) possesses good fluidity and can be used for tablet formulation. Tablets of SD can be prepared by direct compression and have adequate hardness and a small variation in weight. Forces during the tableting process were measured with a tableting process analyzer (TabAll) equipped with a single-punch. The pressure transmission ratio (PTR) from the upper to the lower punch and the die wall force (DWF) were examined during the tableting process. Ejection force (EF) and scraper pressure (SP) were measured for determining the capping and sticking properties during the tableting process. Adding 1% magnesium stearate (MS) to the SD resulted in high PTR and DWF values and a low EF value. PTR and DWF values increased and EF value decreased when MS and microcrystalline cellulose (MCC) were added to the SD. A thousand tablets could be manufactured without problems such as sticking or capping when 1% MS and 50% MCC were added to the SD containing 25% IM.

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To find a new series of arginine vasopressin (AVP) V_1A receptor antagonists, the influence of the 2-phenyl group of 2-phenyl-4′-[(2,3,4,5-tetrahydro-1H-1-benzazepin-1-yl)carbonyl]benzanilide (7) was investigated. Replacement of the 2-phenyl group by a 2-ethyl-1H-imidazol-1-yl group was effective in yielding a V_1A-selective compound. Moreover, this imidazolyl group was introduced in the same position in YM-35471 (6), and further studies of these compounds were performed. Consequently, we found that the (Z)-4′-({4,4-difluoro-5-[(N-cyclopropylcarbamoyl)methylene]-2,3,4,5-tetrahydro-1H-1-benzazepin-1-yl}carbonyl)-2-(2-ethyl-1H-1-imidazol-1-yl)benzanilide (9f) exhibited highly potent affinity and selectivity, and was the most potent antagonist for the V_1A receptor among our compounds. The synthesis and pharmacological evaluation of these compounds are described in this paper

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The impact of microwave drying and binders (copolyvidone and povidone) on the degradation of acetylsalicylic acid (ASA) and physical properties of granules were compared with conventional drying methods. Moist granules containing ASA were prepared using a high shear granulator and dried with hot air oven, fluid bed or microwave (static or dynamic bed) dryers. Percent ASA degradation, size and size distribution, friability and flow properties of the granules were determined. Granules dried with the dynamic bed microwave dryer showed the least amount of ASA degradation, followed by fluid bed dryer, static bed microwave oven and hot air oven. The use of microwave drying with a static granular bed adversely affected ASA degradation and drying capability. Dynamic bed microwave dryer had the highest drying capability followed by fluid bed, static bed microwave dryer and conventional hot air oven. The intensity of microwave did not affect ASA degradation, size distribution, friability and flow properties of the granules. Mixing/agitating of granules during drying affected the granular physical properties studied. Copolyvidone resulted in lower amount of granular residual moisture content and ASA degradation on storage than povidone, especially for static bed microwave drying. In conclusion, microwave drying technology has been shown to be a promising alternative for drying granules containing a moisture-sensitive drug.

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Two new C-3/C-3″ biflavanones, chamaejasmenin D (1) and isochamaejasmenin B (2), were isolated from the roots of Stellera chamaejasme, together with five known biflavanones, chamaejasmenin A (3), chamaejasmenin B (4), neochamaejasmin A (5), sikokianin A (6), and chamaejasmenin C (7). Their structures were elucidated by spectroscopic methods, including 2D NMR techniques. Among these compounds, 1—3 demonstrated potent antimitotic and antifungal activity with minimum inhibitory concentration (MIC) values of 6.25, 6.25, and 3.12 μg/ml, respectively.

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The effects of methyl jasmonate (MeJA) on isoprenoid production were evaluated in cultured tissues of Scoparia dulcis. It was found that MeJA suppressed the accumulation of chlorophylls, carotenoids, phytol and β-sitosterol in the tissues. MeJA, however, remarkably enhanced the production of scopadulcic acid B (SDB) , with 10 μM being optimal observed concentration for stimulation of SDB production. The maximum concentration of SDB was observed 6 d after MeJA treatment.

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A new monoterpene glucoside (1) and three new natural megastigmane glycosides (2—4) were isolated along with a known megastigmane glucoside (5) from twigs with leaves of Juniperus communis var. depressa (Cupressaceae) collected in Oregon, U.S.A., and their structures were determined on the basis of spectral and chemical evidence. In addition, the antibacterial activities of the isolated components against Helicobacter pylori were also investigated.

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An ante-iso type regio-isomer on the long chain base moiety of a glucocerebroside, HLC-2-A, has been isolated from its parent glucocerebroside molecular species HLC-2 composed of iso and ante-iso isomers, from the less polar lipid fraction of a chloroform/methanol extract of the sea cucumber Holothuria leucospilota. Reverse-phase HPLC that included a recycling system was effective in separating the regio-isomer from its counterpart, revealing a very close resemblance in structure. Other typical glucocerebroside molecular species HLC-1 and HLC-3 were obtained together with HLC-2. The structures of these glucocerebrosides were determined on the basis of chemical and spectroscopic evidence.

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An extensive analysis of hydrogen bonding of steroid compounds in diluted solution is preformed by pulsed field gradient (PFG) NMR and cold-spray ionization (CSI)-MS, in the solid state by X-ray crystallographic analysis. The formation of hydrogen bond interaction are quantified and discussed. Although X-ray analysis in the crystalline state and CSI-MS measurement in solution suggested that the observed diffusion coefficient D_obs of the steroid compounds may vary in accordance with the number of hydrogen bonds, the actual observed D_obs value determined from the diffusion studies diminished constantly without correlation on the decreasing numbers of hydrogen bonds. Comparison of two different calibration profiles of calculated molecular volume (V_cal) vs. D_obs, which are obtained from compounds possessing no hydrogen bonding and the steroid compounds, formation of a chain structure (cluster) based on intermolecular hydrogen bonding of the steroid compounds is unambiguously confirmed.

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Using a new method having been developed for the purpose of quantitative determination for peroxyradicals, the presence of peroxyradicals was proved in cigarette smoke. In brief, peroxyradicals in cigarette smoke were measured by ESR spectrometry coupled to non-reductive scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH). As a result, peroxyradicals were found to be major reactive oxygen species (ROS) since the concentration of peroxyradicals recovered from cigarette smoke was much higher than that of any of other ROS (superoxide and hydroxyl radical) and nitric oxide. Furthermore, several antioxidants (ascorbic acid, reduced glutathione, epigallocatechin gallate, shikonin) were examined for scavenging activity against peroxyradicals in the cigarette smoke. Among them shikonin alone exerted the scavenging activity, suggesting that shikonin is promising antioxidant for cigarette filters because of its effectiveness against broad range of ROS including peroxyradicals, heat resistance, nonvolatility and high affinity to the filter.

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Chemical investigation of leaves of Staphylea bumalda DC., collected in the suburbs of Hiroshima City, afforded 11 new megastigmane glucosides, named staphylionosides A—K (3—13), along with two known megastigmane glucosides (1, 2). The relative structures were elucidated from spectroscopic evidence, and the absolute structures of the aglycones were determined by means of the combination of β-D-glucosylation-induced shift-trends and the modified Mosher's method.

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Investigation of an acetone extract of the leaves and twigs of Taxus sumatrana has resulted in the isolation of two new bicyclic taxoids, tasumatrols M (1), and N (2) and a new baccatin III derivative, tasumatrol O (3) together with the previous known 7-deacetylcanadensene (4) and 2α,7β,13α-triacetoxy-5α,9α-dihydroxy-2(3→20) abeotaxa-4(20),11-dien-10-one. The structures of these taxanes were established on the basis of spectroscopic analyses, especially 1- and 2D NMR, and chemical derivatization.

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To characterize the photocatalytic activity of TiO₂ via solid-state reaction, the relationship between the physicochemical properties and photocatalytic activity of TiO₂ was investigated and estimated from the results of photodegradation of nisoldipine. The photodegradation of nisoldipine was significantly enhanced by addition of TiO₂. Two degradation products, nitroso-phenylpyridine derivative and nitro-phenylpyridine derivative, were formed. The degree of photocatalytic activity of TiO₂ was quite different between the various types of TiO₂ investigated, even when the crystalline phase was the same. As a result of the investigations into the relationship between the photocatalytic activity and physicochemical properties of TiO₂, it was found that for the rutile form the photocatalytic activity has good correlation with specific surface area of TiO₂, but poor correlation with water loss on drying of TiO₂. However, for the anatase form, the photocatalytic activity has good correlation with water loss on drying of TiO₂, but poor correlation with specific surface area. Moreover, it was found that the crystallinity of TiO₂ has a moderate correlation with the photocatalytic activity of both crystal forms of TiO₂. These results suggest that a degree of photocatalytic activity of TiO₂ depends on the various physicochemical properties of each type of TiO₂ investigated.

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As a result of a continuing investigation of the biotransformation of ferulic acid with H₂O₂/Momordica charantia peroxidase at pH 5.0 in the presence of acetone, triFA1 (1) and triFA2 (2), two new FA dehydrotrimers, have been isolated. The structures were elucidated from the spectroscopic data including 2D-NMR such as HSQC, HMBC and NOESY data. TriFA1 (1) is a unique FA dehydrotrimer possessing a 3a,9b-dihydro-1H-furo[3,4-c][1]benzopyran-3(4H)-one ring system. The possible mechanism for the formation of triFA1 was also discussed.

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The mechanisms of nitrosation of acetone through sodium enolate [CH₃COCH₂]⁻Na⁺ (1) or naked enolate [CH₃COCH₂]⁻ (2) with tert-butyl nitrite (CH₃)₃CONO (3) were studied using ab initio molecular orbital (MO) methods. When the modified complex model was used in the elimination process, our results demonstrated the predominant formation of E-1-hydroxy-imino-2-oxo-propane CH₃COCH=NOH (4E), in which a counter-cation of the base catalyst did not participate during the reaction. On the other hand, participation of the counter-cation during the reaction contributed to the formation of the Z-isomer of 4 (4Z).

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Two new polyoxygenated cyclohexenes, kweichowenol A and B, were isolated from the leaves of Uvaria kweichowensis, and their structures were established on the basis of their spectral data. The two new compounds showed some antitumour activity by MTT assay.

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A new humulene sesquiterpene, 5-hydroxyzerumbone (5-hydroxy-2E,6E,9E-humulatrien-8-one) (1) and a known compound, zerumboneoxide (2) were isolated from the rhizomes of Zingiber zerumbet (Zingiberaceae), and found to inhibit lipopolysaccharide-induced nitric oxide production in murine macrophage RAW 264.7 cells with IC₅₀ values of 14.1 and 23.5 μM, respectively, by bioassay-guided fractionation (positive control: N^ω-monomethyl-L-arginine, IC₅₀=21.3 μM). The structure of 1 was determined by spectroscopic methods including 1D and 2D-NMR.

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A bioassay-guided isolation of the ethanol extract from the fruits of Piper longum yielded a known piperidine alkaloid, piperine, as a monoamine oxidase (MAO) inhibitor. Piperine showed an inhibitory effect against MAO-A (IC₅₀ value: 20.9 μM) and MAO-B (IC₅₀ value: 7.0 μM). Kinetic analyses by a Lineweaver–Burk plot clearly indicated that piperine competitively inhibited MAO-A and MAO-B with K_i values of 19.0±0.9 μM and 3.19±0.5 μM, respectively. The inhibition by piperine was found to be reversible by dialysis of the incubation mixture. In addition, the immobility times in the tail suspension test were significantly reduced by piperine, similar to that of the reference antidepressant fluoxetine, without accompanying changes in ambulation when assessed in an open-field. These results suggest that piperine possesses potent antidepressant-like properties that are mediated in part through the inhibition of MAO activity, and therefore represent a promising pharmacotherapeutic candidate as an antidepressant agent.

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A new phytoecdysteroid, namely ajugalide-E (1), together with twenty five known compounds were isolated from Ajuga taiwanensis collected from Tainan, Taiwan. Their structures were determined by spectral analysis including high resolution one- and two-dimensional NMR spectroscopy.

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Two novel sapogenols, isoesculeogenin A (1) and esculeogenin B (2) of steroidal alkaloid glycosides, lycoperoside F and esculeoside B, respectively, isolated from the ripe tomato have been characterized as (5α,22R,23R,25S)-3β,23,27-trihydroxyspirosolane and (5α,22S,23R,25S)-22,26-epimino-16β,23-epoxy-3β,23,27-trihydroxycholestane, respectively.

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Two new sesquiterpene lactones with the unusual sulfonic acid group, 13-sulfo-dihydrosantamarine (1) and 13-sulfo-dihydroreynosin (2), have been isolated from the roots of Saussurea lappa C. Their structures, including the absolute configurations, were elucidated by spectroscopic methods.

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To expand the sequence of double-stranded DNA (dsDNA) targets in a triplex formation, 2′,4′-BNAs (2′-O,4′-C-methylene bridged nucleic acids) having imidazoles as a nucleobase were synthesized and incorporated into oligonucleotides. Triplex-forming ability of the modified oligonucleotides was evaluated by using melting temperature (T_m) measurements.

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Two new isoflavanone and one new 3-arylcoumarin derivatives, along with a known compound 3,4-didehydroglabridin, were isolated from commercially available licorice of Glycyrrhiza glabra origin, and their structures were elucidated on the basis of both the chemical and spectroscopic evidence.

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A new caged-tetraprenylated xanthone, hanburinone (1), was isolated from the fresh fruits of Garcinia hanburyi together with four known caged-tetraprenylated xanthones; isomoreollin B (2), morellin (3), moreollic acid (4) and morellic acid (5). Their structures were elucidated by analysis of spectroscopic data and comparison of the NMR data with those reported previously. Compounds 4 and 5 showed moderately antibacterial activity against methicillin-resistant Staphylococcus aureus with a MIC value of 25 μg/ml.

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Two new compounds, taraxafolide (1) and (+)-taraxafolin-B (2) together with eighteen known compounds, which include one sesquiterpene, thirteen benzenoids, two indole alkaloids, one pyridine derivative and steroid mixtures were isolated and characterized from the fresh roots of Taraxacum formosanum. Structures of new compounds were determined by spectral analysis. (+)-Taraxafolin-B had the bioactive caffeic acid moiety, but its activity was weaker than α-tocopherol in DPPH radicals scavenging activity assay.

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Patchoulic oil, the volatile oil of Pogostemon cablin (BLANCO) BENTH. and the Chinese crude drug Herba Pogostemonis, is widely used in the cosmetic and oral hygiene industries. Patchoulic alcohol is commonly used as an indicator for the quality assessment of dried P. cablin. However, the complexity of the herbal constituents makes it difficult for using conventional gas chromatography (GC) for analytical purpose. The present study established an accurate, sensitive and reproducible method for the quality assessment of the dried patchouli herb based on patchoulic alcohol content. A gas chromatography-tandem mass spectrometry (GC/MS/MS) method has been successfully developed and demonstrated for the determination of patchoulic alcohol content in the samples of dried P. cablin. The developed method was found to be convenient and facile in particular to tackle the complicated matrix problems always encountered in the herbs which contain high level of essential oils.

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A new highly oxygenated pseudoguaianolide, 8-β-acetoxyhysterone C, along with the known compounds, parthenin, coronopilin and hysterone C, has been isolated from a collection of the flowers of Parthenium hysterophorus. The structure of the new compound was derived from the extensive studies of its spectral (mainly 1D and 2D NMR) data.

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In this communication, we discuss the characterization of DNA conjugate synthesized by mechanochemical polymerization, Con-M, on the separation of model oligo-DNA and its single nucleotide polymorphisms (SNPs) by affinity capillary electrophoresis, compared with that prepared by radical-initiated solution polymerization, Con-RL. The average molecular weight of Con-M was similar to that of Con-RL, although the molecular weight distribution of Con-M was narrower than that of Con-RL. Capillary electrophoresis of oligo-DNA was performed using the capillary filled with DNA conjugate. The resolution of the capillary filled with Con-M was apparently higher than with Con-RL. It is considered that higher resolution using the capillary filled with Con-M could be ascribed not only to the narrow molecular weight distribution but also to the difference of copolymer structure.

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The microbial transformation of (+)-catechin (1) and (−)-epicatechin (2) by endophytic fungi isolated from a tea plant was investigated. It was found that the endophytic filamentous fungus Diaporthe sp. transformed them (1, 2) into the 3,4-cis-dihydroxyflavan derivatives, (+)-(2R,3S,4S)-3,4,5,7,3′,4′-hexahydroxyflavan (3) and (−)-(2R,3R,4R)-3,4,5,7,3′,4′-hexahydroxyflavan (7), respectively, whereas (−)-catechin (ent-1) and (+)-epicatechin (ent-2) with a 2S-phenyl group resisted the biooxidation.

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Racemic compound (1) of the antimalarial agents febrifugine (d-1) was synthesized using an stereoselective Michael reaction of an ω-amidoenone (5) which was prepared by the Wittig reaction of piperidinediol (7).

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