Five new maleic and succinic acid derivatives were isolated from the mycelium of Antrodia camphorata. Their structures were determined by various spectroscopic means. Maleimide derivatives 2 and 3 showed appreciable cytotoxic activity against LLC cells.
Observations of Raman spectra of various molecules at different exciting laser wavelengths lead to an empirical rule. If a Raman line becomes stronger when the exciting frequency is brought closer to the frequency of an electronic band, this means that the equilibrium conformation of the molecule is distorted along the normal coordinate for the Raman line in the transition from the ground to the excited electronic state.
The Raman spectrum of tryptophan has been observed in its neutral aqueous solution with 514.5, 488.0, 457.9, 363.8, and 257.3 nm excitation. The effects of N‐deuteration and 15N‐substitution of the indole ring on the Raman spectrum have been examined. A preliminary normal coordinate treatment of the indole ring has also been made. On the basis of these data, the vibrational mode and a possible origin of the Raman scattering intensity has been discussed for each of the 1623, 1555, 1436, 1344, 1016, 882, and 762 cm−1 Raman lines of tryptophan. The resonance enhanced line at 1623 cm−1 has been assigned to a vibration of the indole ring which is related to the b3g ring stretching vibration of naphthalene at 1636 cm−1. Its intensity is considered to come almost solely from the B̃ ← X̃ (La) electronic transition at 273 nm. It is therefore probable that the geometrical structure of the molecule is distorted along this vibrational coordinate on going from the ground (X̃) to the B̃ electronic excited state.
For quantitative determination of 19 triterpene constituents, including six ganoderma alcohols (1-6) and 13 ganoderma acids (7-19), in the products of Ganoderma lucidum, an analytical system was developed using high-performance liquid chromatography with an ODS column. The mobile phase was a linear gradient of 1% AcOH/H 2 O-CH 3 CN and 2% AcOH/H 2 O-CH 3 CN, and the elution profile was monitored at 243 and 250 nm for ganoderma alcohols and acids, respectively. The relative standard deviations of this method were less than 2.35% and 2.18% (n)5؍ for intraday and interday assays, and the recoveries were 90.9-100.8% and 93.4-103.9% for constituents of alcohol and acid groups, respectively. This system was applied to a quantitative determination of the constituents in 10 different products of G. lucidum: six usual umbrella forms of the fruiting bodies, three antlered forms of the fruiting bodies and spores, and eight specimens from the same G. lucidum strain, which was parasitized on logs from different plants or different fungus beds. The analytical results indicated that the quantity and composition of these triterpenes differed appreciably among various specimens, but the relative ratio of the alcohols and acids was not significantly different when the same strain of G. lucidum was used.
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