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One new anthraquinone glycoside, 6-O-(α-L-rhamnopyranosyl-(1→6)-β-d-glucopyranosyl)emodin (1), and two new sesquilignans, seslignanoccidentaliols A (2) and B (3), were isolated from the whole plant of Cassia occidentalis. The structures of the new compounds were established by means of spectroscopic methods, especially 2D-NMR data (1H,1H-COSY, HMQC, HMBC, and ROESY), as well as HR-ESI-MS analysis. One previously reported sesquilignan, erythro-guaiacylglycerol-β-O-4′-(5′)-methoxylariciresinol, was revised to be seslignanoccidentaliol A (2). The 6-O-(α-L-rhamnopyranosyl-(1→6)-β-d-glucopyranosyl)emodin (1) exhibited moderate anti-HIV-1 activity with an EC50 value of 2.90 μg/ml and a therapeutic-index (TI) value of 260. [ABSTRACT FROM AUTHOR]

Two new iridoid alkaloids, daphmacropodosidines 4;A (1) and B (2), together with two known ones, daphcalycinosidine 4;B and caldaphnidine 4;F, were isolated from the fruits of Daphniphyllum maropodum. Their structures were established by spectral methods, especially 2D NMR spectra (1H,1H-COSY, HMQC, HMBC, and NOESY), as well as chemical means. [ABSTRACT FROM AUTHOR]

A novel bisabolane-type sesquiterpenoid lactone, glochicoccin A (1), and three new norbisabolane sesquiterpenoids, glochicoccins B–D (2–4), together with two known norbisabolane sesquiterpenoids, phyllaemblic acid (5) and phyllaemblic acid methyl ester (6), were isolated from the rhizomes of Glochidion coccineum. Their structures were elucidated by different spectroscopic (IR, UV, NMR) and mass-spectrometric (MS) techniques. The structure and relative configuration of 1 was confirmed by single-crystal X-ray diffraction (Fig. 4;2). None of the compounds were found to exhibit cytotoxic or antioxidant activities. [ABSTRACT FROM AUTHOR]

In this paper, 1.2 kV, 3.3 kV, and 5.0 kV class 4H–SiC power Schottky barrier diodes (SBDs) are fabricated with three N-type drift layer thickness values of 10 μm, 30 μm, and 50 μm, respectively. The avalanche breakdown capabilities, static and transient characteristics of the fabricated devices are measured in detail and compared with the theoretical predictions. It is found that the experimental results match well with the theoretical calculation results and are very close to the 4H–SiC theoretical limit line. The best achieved breakdown voltages (BVs) of the diodes on the 10 μm, 30 μm, and 50 μm epilayers are 1400 V, 3320 V, and 5200 V, respectively. Differential specific-on resistances (Ron−sp) are 2.1 mΩ ·cm2, 7.34 mΩ·cm2, and 30.3 mΩ·cm2, respectively. [ABSTRACT FROM AUTHOR]

In this paper, the normally-off N-channel lateral 4H–SiC metal–oxide–semiconductor field-effect transistors (MOSFFETs) have been fabricated and characterized. A sandwich- (nitridation–oxidation–nitridation) type process was used to grow the gate dielectric film to obtain high channel mobility. The interface properties of 4H–SiC/SiO2 were examined by the measurement of HF I–V, G–V, and C–V over a range of frequencies. The ideal C–V curve with little hysteresis and the frequency dispersion were observed. As a result, the interface state density near the conduction band edge of 4H–SiC was reduced to 2 × 1011 eV−1·cm−2, the breakdown field of the grown oxides was about 9.8 MV/cm, the median peak field-effect mobility is about 32.5 cm2·V−1·s−1, and the maximum peak field-effect mobility of 38 cm2·V−1·s−1 was achieved in fabricated lateral 4H–SiC MOSFFETs. [ABSTRACT FROM AUTHOR]

Five new triterpenoids, serrulatins A–E (1–5), including two new artifacts, together with ten known serrulatins, were isolated from the edible leaves of Photinia serrulataafter extraction and purification. Their structures were identified on the basis of spectroscopic methods including 2D NMR experiments. Compounds 1and 3are unusual ursolic triterpenoids characterized by the occurrence of a C(13)C(18) bond. [ABSTRACT FROM AUTHOR]