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A reinvestigation of the NMR and IR results for natural schizocommunin led the researchers to propose a revised structure, quinazolinone. We suggested that if a CASE approach were used elucidate the structure when this compound was firstly isolated, the structure revision would be not necessary: for final structure confirmation X-ray crystallographic analysis would be sufficient.

Mass spectrometry (MS) is a valuable tool that can give you vast amounts of MS data to help you identify and quantify components. MS has been used to discover, determine, and quantify sample compounds in the proteomics, metabolomics, imaging, and glycomics applications across the food, pharmaceutical, and environmental industries. Combining MS with appropriate software and computer technology allows the possibility for more extensive applications. But first, we must understand the basics.

The ethyl acetate layer of T. matsutake was fractionated and purified by repeated chromatographic methods to yield the white powder matsutakone, molecular formula C28H44O4. The structure of Structure of matsutakone was elucidated from its molecular formula and 1D and 2D NMR data shown in Table 1, which were used by us for challenging ACD/Structure Elucidator.

The Penicillium sp. KFS28 fungus was isolated from a bivalve mollusk, Meretrix Lusoria, from the Haikou Bay in China. The EtOAc extract of the fermentation broth was processed by the authors who isolated and identified four new paxilline-type indole-terpenoids. Compound 1 has the molecular formula C28H35NO6.

Fei and co-workers4 isolated Euphorikanin A (molecular formula C20H26O3), a structurally novel diterpenoid lactone with an unprecedented carbon skeleton featuring a unique tetradecahydrobenzo[cd]-cyclopropa[f ]azulene. Its structure was determined by spectroscopic methods and confirmed by single crystal X-ray analysis.

A calculated neutral loss spectrum is obtained from a mass spectrum by determining the mass differences between the precursor ion m/z and each of the other peaks in the spectrum and plotting the original intensity versus neutral mass. Neutral losses with small masses have limited possibilities for their composition and thus can facilitate the identification...

The nomenclature rules for organic compounds set by the International Union of Pure and Applied Chemistry (IUPAC) committee (http://www.iupac.org/) do offer flexibility in some areas especially in cases where old publications have old terms. Below are some examples. The answers for the structures, as based on the IUPAC nomenclature rules, are listed below. Some links...

Chen et al have been looking for novel secondary metabolites from Trichoderma gamsii, a plant endophytic fungus. As a result of this a new polyketide trichoderpyrone (molecular formula C15H17NO5), containing a unique cyclopentenone−pyrone hybrid skeleton was isolated and its structure was determined by detailed analysis of NMR data.