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4-(2-Methylbutyryl)-4H-tomentosin (I), a new xanthanolide from the whole plant of Carpesium macrocephalum, is isolated along with nine known sesquiterpenes.

Polyethylene glycol (PEG) and diacetate cellulose (CDA) exhibit good miscibility in acetone solution. The miscibility is related to the molecular weight of PEG, which increases as miscibility decreases. The phase-change behavior of PEG in composite with CDA prepared from the miscible solution was found to be completely different from that of pure PEG. When the PEG fraction in the composites was less than 85%, PEG within the composite did not melt into liquid; even when the temperature was 40°C higher than the melting point of PEG, the PEG–CDA composite exhibited solid–solid phase-change behavior. Thermal analysis indicated that the PEG–CDA composite had greater enthalpy and exhibited good thermal stability. The PEG–CDA composite that exhibited solid–solid phase-change behavior can be used as a new kind of phase-change material for thermal energy storage and temperature control. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 652–658, 2003

Nineteen kinds of minerals, alone and in bicomponent mixtures with LaC (a mixed ternary complex of trivalent lanthanum stearate and stearin), were added to isotactic polypropylene (iPP). The influences of the minerals on the crystallographic forms of iPP were investigated. A wide-angle X-ray diffraction examination demonstrated that no mineral or LaC acting alone could induce the occurrence of the hexagonal β-form, whereas the bicomponent mixtures could when the mineral was a calcium compound or contained calcium compounds, whether the calcium compounds had a hexagonal crystallographic form or not. We surmise that the actual β-iPP substrate in such a system might be some binuclear complexes of calcium and rare earth elements with some specific ligands. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1742–1748, 2002

Absorption of a series of low molecular weight solutes into polyurethane was investigated in supercritical carbon dioxide with different conditions. The effect on the amount of solutes absorbed in polyurethane due to these factors such as pressure, temperature, absorption time, decompression time, the character of solutes, and the amount of cosolvent was examined by a gravimetric method. The absorption mechanism was discussed. The desorption of solutes in polyurethane showed a dependence on the logarithm of time.

A phytochemical investigation of the roots of Euphorbia prolifera led to the isolation of ten new myrsinol diterpenes, named euphorbialoids A-J (1-10), and two known analogues (11 and 12). Their structures were elucidated on the basis of extensive 1D and 2D NMR (COSY, HMQC, HMBC and NOESY) spectroscopic data analyzes, and the structures of 1 and 9 were confirmed by X-ray crystallography. The inhibitory activities on LPS-induced NO production of these diterpenes were evaluated and all the compounds showed inhibitory effects.

A new clerodane diterpene, 15-hydroxy-16-acetoxy-ent-clerod-3-en-18-oic acid (1), together with three known clerodane diterpenes (2-4) and three known flavones (5-7), were isolated from the aerial parts of Baccharis gaudichaudiana. Their structures were elucidated on the basis of spectroscopic analysis. Compounds 2, 3, and 5 showed enhancing activity of nerve growth factor (NGF)-induced neurite outgrowth in PC 12D cells.

A new iridoid glycoside, 10-isovaleryl kanokoside C (1), and a new sesquiterpene (2) together with two known compounds (3, 4) were isolated from the rhizomes and roots of Valeriana fauriei. Their structures were elucidated on the basis of spectroscopic analysis. Compounds 2 and 4 showed enhancing activity of nerve growth factor (NGF)-induced neurite outgrowth in PC 12D cells.