Purification of the n-BuOH fraction of the aqueous alcoholic extract from the roots of Phytolacca americana resulted in the isolation of two triterpene saponins named esculentoside B (1), and esculentoside A (2). The structures of isolated compounds were characterized on the basis of extensive spectral data (1D and 2D NMR; and MS) and in comparison with their Nuclear Magnetic Resonance (NMR) an...

The phytochemical studies of Eschweilera longipes Miers (Lecythidaceae) have led to the identification of a new triterpene 3beta, 24-dihydroxyfriedelane, the known 1beta, 2beta, 3beta, 19beta-tetrahydroxyurs-12-en-28-oic acid (1beta-hydroxyeucaphic acid) besides the saponin sitosterol 3betaO-betaD-glucopyranoside. The structures were established from the IR, NMR and mass spectra data including ...

UNLABELLED BACKGROUND Electrospray tandem mass spectrometry approach is widely used for the rapid characterization of natural products. This paper describes the gas-phased ESI-MS/MS fragmentation of abietane-type diterpenoids and their novel dimeric conjugate, salvialeriafone (1) using both positive and negative ion electrospray ionization quadropole time-of-flight mass spectrometry (ESI-QqT...

The Far Eastern sea cucumber Eupentacta fraudatrix is an inhabitant of shallow waters of the south part of the Sea of Japan. This animal is an interesting and rich source of triterpene glycosides with unique chemical structures and various biological activities. The objective of this study was to investigate composition and distribution in various body components of triterpene glycosides of the...

The fragmentation of free tenfold protonated ubiquitin in intense 70 femtosecond pulses of 90 eV photons from the FLASH facility was investigated. Mass spectrometric investigation of the fragment cations produced after removal of many electrons revealed fragmentation predominantly into immonium ions and related ions, with yields increasing linearly with intensity. Ionization clearly triggers a ...

The destructive output of the PMN mine was assessed experimentally by detonating actual mines in air and then in soil. The fragmentation pattern was recorded using a combination of flash X-rays, fragmentation packs, and gelatine cylinders. This made it possible to measure the velocity as well as the mass of the fragments, so that their injury potential could be estimated. This report describes ...

H.-R. Schulten and W. D. Lehmann Institute of Physical Chemistry, University of Bonn, Wegeierstraße 12, D-5300 Bonn Z. Naturforsch. 83 b, 770-781 (1978); received March 21, 1978 Field Desorption Mass Spectrometry, a-Amino Acid Methionine The fragmentation of methionine in field desorption mass spectrometry has been studied. Decomposition mechanisms are described which are based on stable isotop...

The microalga Botryococcus braunii (B. braunii) can produce extracellular oil in the form of triterpenoid hydrocarbons up to 40 precent of their dry mass. These hydrocarbons with carbon chain lengths ranging from C30 to C40 including botryococcene, squalene and methylated squalenes, are ideal for the production of high quality liquid transport fuels and petrochemical alternatives. However, comm...