制备反相高效液相色谱法用于从杉材中分离制备倍半萜类化合物

利用制备高效液相色谱法从日本产杉材(Cryptomeria japonica D.Don)中分离制备倍半萜类化合物。在YWC-Pack C18柱上,以异丙醇-甲醇-正己烷-水(体积比为50∶35∶10∶5)为流动相,流速为5 mL/min,制备了2种倍半萜类化合物,经紫外光谱、红外光谱及核磁、质谱分析,确认它们分别为(-)-cubebol和(+)-2,7(14),10-bisa-bolatrien-1-ol-4-one。所制备的两个化合物的纯度分别为98.7%和99.1%。     

Anion chromatography using on-line recycled eluents

Non-suppressed anion chromatography, using on-line recycled eluents, was investigated. Cations and anions from samples were excluded from the eluents using a mixture of strongly acidic cation-exchange resins and strongly basic anion exchange resins in the eluent reservoir. This exclusion was performed after determination of the anions in the non-suppressed anion chromatography, and the eluents were then recycled on-line. The performance of consecutive determinations was evaluated from the relative standard deviation (RSD) of peak heights and retention times of chloride, bromide, nitrite, nitrate, and sulfate ions, with a concentration of 3 microg ml(-1) each, compared to that of normal anion chromatography. Over 50 consecutive determinations could be achieved with an eluent volume of only 200 ml for a 100 microl sample volume. Almost all the RSD values for retention time, and peak heights of these anions, were smaller than 3%. Over fifty consecutive determinations of chloride, nitrate, and sulfate ions in a river water sample could be achieved with an eluent volume of only 100 ml. All the RSD values for retention time and peak heights of these anions were smaller than 3%. The eluent volume could be decreased to one tenth of that used in normal anion chromatography. The performance of the anion chromatography, using on-line recycled eluents, was the same as that for normal anion chromatography under the same conditions.     

Crystal and molecular structures of cis-1-phenyl-3-piperidinocyclohexan-1-ol hydrochloride

Mr = 295.84, triclinic, Pl, a = 6.786(1), b = 7.658(1), c = 8.561(1) Å, α = 108.17(1), β = 97.94(1), γ = 103.32(2)°, V = 400.6 ų, Z = 1,D_m = 1.23, D_x = 1.226 Mgm^?3, δ(Cu Kα) = 1.5418 Å, μ = 20.81 cm^?1, F(000) = 160. The structure has been solved by direct and Fourier methods and refined by a least-squares procedure to the final R = 0.043 for 1182 observed reflections (|F_o] >3σ(F_o)). cis-1-Phenyl-3-piperidinocyclohexan-1-ol possessing 1,3-diaxial positions between the piperidine and hydroxyl groups is converted to the isomer with 1,3-diequatorial positions in its hydrochloride. The hydrogen bond is formed between the chloride anion and the protonated nitrogen atom of piperidine instead of the intramolecular hydrogen bond in the free cis-base between the oxygen and nitrogen atoms.     

Long-term behavior of 137Cs and 3H activities from TEPCO Fukushima NPP1 accident in the coastal region off Fukushima,Japan

Journal of Radioanalytical and Nuclear Chemistry - Decreasing trends of both 137Cs and 3H activity concentrations and an increasing trend of 3H/137Cs activity ratio at Fukushima Dai-ichi Nuclear...     

Two-dimensional hopping motion of encapsulated La atoms in silylated La(2)@C(80)

The (139)La NMR study of the exohedrally functionalized derivatives of La(2)@C(80) metallofullerene, La(2)@C(80)(Ar(2)Si)(2)CH(2) (: Ar = Mes, Mes = mesityl, : Ar = Dep, Dep = 2,6-diethylphenyl), reveal that the two La atoms hop between two sites along the equator of the C(80) cage.     

Conformation and location of membrane-bound salinomycin-sodium complex deduced from NMR in isotropic bicelles

An ionophore antibiotic salinomycin was studied in a membrane environment consisting of isotropic bicelles, a better model for biological membranes than micelles, and its conformation and topological orientation in bicelles was determined. 2D NMR measurements and restrained conformational search revealed that salinomycin-sodium salt in bicelles adopts an open conformation in which the orientation of the E-ring is significantly different from that in crystal and solution structures. This conformational alteration breaks an intramolecular hydrogen bond between 28-OH and 1-O, dislocates the ether oxygen of the E-ring from a coordinated position to the sodium ion observed in the crystal, and consequently weakens the complexation between salinomycin and the sodium ion. Paramagnetic relaxation experiments using doxyl-phospholipids reveal that salinomycin is embedded shallowly in bicelles, with both terminals being closer to the water interface and the olefin portion facing the bicelle interior. Measurements of intermolecular NOEs between salinomycin and phospholipids further supported this orientation. Weaker complexation with sodium ion and positional preference in the membrane polar region may facilitate the catch-and-release of metal ions at the polar/nonpolar interface of bilayers. On the basis of these findings, a model for salinomycin-assisted transport of metal ions across biological membranes is proposed.     

Three new sulfur-containing alkaloids, polycarpaurines A, B, and C, from an Indonesian ascidian Polycarpa aurata

Three new sulfur-containing alkaloids, polycarpaurines A (1), B (2), and C (3) were isolated from the tropical ascidian Polycarpa aurata collected in Indonesia, together with six known compounds (4-9). The structures of new compounds were assigned on the basis of their spectral data. Compounds 1, 3, 4, and 8 inhibited colony formation of Chinese hamster V79 cells with EC₅₀ values of 6.8, 8.6, 3.8, and 10 μM, respectively. Compounds 2 and 7 showed modest activity against V79 cells (EC₅₀>10 μM).     

Sex-related Differences in Exercise Capacity Trends and Determinants after Cardiac Rehabilitation in Patients with Acute Myocardial Infarction

Objective: This study aimed to investigate whether longitudinal changes in exercise capacity in patients with acute myocardial infarction (AMI) differ by sex and clarified what contributed to these differences. Methods: We retrospectively examined the differences in each variable between men and women in 156 patients with AMI (mean age: 65 ± 12 years; 82.0% male) who participated in a 3-month cardiac rehabilitation (CR) program and could be followed-up for exercise capacity 12-months after AMI onset. Sex-related differences in the change in peak oxygen uptake (peak VO₂) at baseline, 3-months, and 12-months after AMI were analyzed. Results: Male patients with AMI were younger and had higher body mass index and employment rate than women. The attendance of the CR program was higher in women (men vs. women; 10 [3–15] vs. 14 [11–24] sessions, p = 0.0002). Women showed a significant lower %change in peak VO₂ after 12 months (men vs. women; 7.8% [–0.49% to 14.6%] vs. 1.3% [–5.7% to 7.5%], p = 0.013). In multiple linear regression analysis, age (β = –0.76, 95% confidence interval [CI] = –1.0 to –0.50, p <0.0001) and female sex (β = –6.3, 95% CI = –9.1 to –3.5, p <0.0001) were negative independent predictors of change in peak VO₂ over 12 months, while CR attendance (β = 0.21, 95% CI = 0.0032–0.42, p = 0.047) and recommended exercise habit after the CR program (β = 2.1, 95% CI = 0.095–4.1, p = 0.040) were positive independent predictors of change in peak VO₂ over 12 months. Conclusion: In female patients, exercise capacity improved during the CR program but decreased to AMI onset levels after 12 months.