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Hungarian drug manufacturer deploys suite of software tools that assist with structure-based drug design at one of its research facilities in Budapest. Toronto, Canada (January 8, 2009)—Egis Pharmaceuticals, one of the leading pharmaceutical companies in Central Europe, sought to increase the efficiency of its Chemical Research Division, and has now done so by implementing software...

Trichilianone D Trichilia species, a genus of plants from the Meliaceae family, are found in tropical forests and are used in traditional medicine. This species is poorly investigated and so a phytochemical study was published just recently [1]. This included the isolation of metabolites and the testing for antileishmanial activity. The study was focused on...

This article discusses how using the mean of the LRI values predicted by RapidMiner and ACD/ChromGenius, in combination with accurate mass data, could enhance the confidence level for compound identification from the analysis of complex matrixes; the goal being to reduce the list of putative candidates to a reasonable number that can be obtained and...

Structure verification is a key activity that an NMR spectroscopist undertakes every day. Reliably labeling structures as “correct” or “incorrect” is not always an easy task and is often entrusted to automated systems for execution. It is not uncommon, however, that the proposed structure that the recorded dataset is to be checked against is biased...

I got some great comments from Tony and Gary on the “Dealing with a Mixture…” post that I decided to do a follow-up post. http://acdlabs.typepad.com/elucidation/2008/02/dealing-with-a.html In my lab days, I would routinely workup a newly acquired 1H NMR for an unknown sample prior to acquiring a 2D NMR dataset. One of my goals was to examine...

Rings plus Double Bonds Equivalent (RDBE) (also known as the degree/element of unsaturation or index of hydrogen deficiency) can be determined from a Molecular Formula (MF). The calculation provides insight into the number of rings and/or double bonds and/or triple bonds to expect from an unknown structure. RDBE = (# of C) + 1 –...

In light of the posting by Oliver Fiehn’s group (http://fiehnlab.ucdavis.edu/projects/Seven_Golden_Rules/Ring-Double-Bonds/), I’ve decided to blog some compounds I’ve encountered in the lab. Using the 2nd formula from the previous blog (http://acdlabs.typepad.com/elucidation/2008/03/rings-double-bo.html), for some cases the RDBE calculation will work if the correct atom valence is known. Note: the nitrochloroform compound can be drawn more than one...

Here is a lesson I learnt over time while working on small molecules—my Elucidation Evolution. Thinking back to when I started doing elucidations of unknowns, my mindset was to collect loads of data (NMR, MS, IR, etc.) whether I needed it or not. Initially inexperienced, I was extracting bits and pieces of information from various...

When trying to elucidate an unknown structure using 2D NMR information, an elucidator gains an advantage by analyzing all of the NMR data as a whole rather than as individual pieces. Although complicated at first, this different perspective at viewing the NMR data can facilitate the elucidation process. The following list are a few advantages...

With a well-tuned and calibrated, high resolution MS instrument, a molecular formula(e) can be devised from the m/z for an ion peak. In cases where more than one molecular formula fits, knowing the accuracy of the MS instrument can help in narrowing down the choices. The first step is to identify the molecular ion peak...