Comments on: N15 NMR, Performance Validation of Prediction Algorithms based on Alkaloids http://www.chemspider.com/blog/n15-nmr-performance-validation-of-prediction-algorithms-based-on-alkaloids.html Building Community for Chemists Tue, 14 May 2013 21:50:31 +0000 hourly 1 http://wordpress.org/?v=3.5 By: Antony Williams http://www.chemspider.com/blog/n15-nmr-performance-validation-of-prediction-algorithms-based-on-alkaloids.html/comment-page-1#comment-724 Antony Williams Sun, 01 Jul 2007 16:41:12 +0000 http://www.chemspider.com/blog/?p=59#comment-724 Egon, I’ll be assembling all of the structures from this review article shortly to use as test submissions to the deposition system of ChemSpider. When that is done then I’ll be able to provide you with the set of InChI codes. It’ll be a few weeks…apologies but many other distractions right now.

In regards to 195Pt prediction …which I think is your question…I’m not aware of any prediction programs out there. I have measured 195Pt spectra myself a few years ago…great nucleus. It was during a time of messing around with 125Te, 77Se and 51V. I really enjoyed playing with the exotic nuclei. There have been reports on 195Pt shifts and deriving prediction equations for a small related set would likely be very easy. However, for general chemical space for all variants of Pt compounds would be challenging since there is likely a fairly small training set. A good reference text by the way is “R.K. Harris and B.E. Mann in NMR and the Periodic Table, Academic Press, London, UK, 1978. ISBN: 0123276500 9780123276506″

In regards to your third question I will comment on that in a separate blog. I definitely have opinions on that!

]]> By: Egon Willighagen http://www.chemspider.com/blog/n15-nmr-performance-validation-of-prediction-algorithms-based-on-alkaloids.html/comment-page-1#comment-694 Egon Willighagen Sat, 30 Jun 2007 05:21:02 +0000 http://www.chemspider.com/blog/?p=59#comment-694 Please provide a list of InChI’s for the test compounds. I can then check how good the NMRShiftDB does. The compound on the cover looks like InChI=1/C11H13F2N5O/c12-7-4-8(18-9(7)13)10(19)15-3-1-2-6-5-16-11(14)17-6/h4-5,18H,1-3H2,(H,15,19)(H3,14,16,17).
The NMRShiftDB does not contain many 15N spectra, and actually fails to assign shifts to two of the five nitrogen nucleis in this compound.

What about 195Pt?

Seriously, 13C, 1H and 15N are quite often used, but with current the current NMR apparatus other nuclei are becoming more easily too… what do you think are the odds that we’ll measure the NMR for all nuclei in the molecule we think we have made?

]]> By: Ryan's Blog on NMR Software http://www.chemspider.com/blog/n15-nmr-performance-validation-of-prediction-algorithms-based-on-alkaloids.html/comment-page-1#comment-687 Ryan's Blog on NMR Software Fri, 29 Jun 2007 20:44:44 +0000 http://www.chemspider.com/blog/?p=59#comment-687 N15 NMR Prediction Validation and Lighthouses

Tony at the ChemSpider Blog points us to two gems. A peek at an 15N NMR prediction validation study that was conducted during the writing of a book chapter to be published by Gary Martin in the book entitled Modern

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