Computer-assisted peer reviewing of spectral data: the CSEARCH protocol

Abstract

Published spectral data used in the process of structure elucidation of organic compounds cover a wide range of quality including many examples of poor characterization of the structure under investigation. The CSEARCH-Robot-Referee has proven its excellent capabilities in detecting inconsistencies between a given structure proposal and the 13 C NMR spectral data used for determination. The combination of this automatic structure verification tool with subsequent generation of alternative structure proposals allows fully automatic structure revisions. From the examples given here, the urgent need for a repository of already measured NMR spectra allowing automatic peer reviewing of new conclusions drawn from spectral data is clearly shown.

The Advantage of Automatic Peer-Reviewing of 13C-NMR Reference Data Using the CSEARCH-Protocol

“…The automatic structure verification based on 13 C-NMR chemical shift data is the central procedure within the “CSEARCH-Robot-Referee” [ 3 , 26 , 27 , 28 ]. The knowledge base behind consists of some 340,000 curated 13 C-NMR spectra taken from the public domain literature.…”

Temperature dependent analysis of Octenidine (N,N´-(decane-1,10-diyldipyridin-1-yl-4-ylidene)dioctan-1-amine) dihydrochloride by NMR and NIR spectroscopy

“…Especially the 13 C prediction tool is even used to check the quality of submitted 13 C NMR shift data for inconsistencies by organic chemistry journals. 10 For the two different canonical forms I and II with the positive charge located at the nitrogen atom (we named these resonance structures pyridinium and iminium ions compared to the remaining three mesomeric structures named carbenium ions 1-3, Scheme 1 and Fig. S3), the predicted values are given in Tables S1 and S2.…”

Structure Elucidation of the spiro-Polyketide Svalbardine B from the Arctic Fungal Endophyte Poaceicola sp. E1PB with Support from Extensive ESI-MSn Interpretation

“… a 1 H NMR recorded at 600 MHz; 13 C NMR recorded at 150 MHz, HMBC correlations as H→C. b 1 H NMR recorded at 500 MHz; 13 C NMR recorded at 125 MHz. c w: weak correlation. d Final assignments were verified using online CSEARCH Robot Referee () e,f Assignments with identical superscript are interchangeable. …”