ACD/Structure Elucidator Suite—Elucidate Unknown Structures

Full List of Features

ACD/Structure Elucidator Suite includes other applications on the Spectrus Platform for full processing of all the analytical techniques that can be used in an elucidation. 1D and 2D NMR is processed via ACD/NMR Workbook Suite; MS data through ACD/MS Workbook Suite; and ACD/Spectrus Processor handles UV-Vis/IR/Raman and Chromatography data.

Spectral Data Import

  • Import raw or processed NMR, UV/IR, and MS data directly into the software via drag-and-drop.
  • Enter compositional information such as MS data, known Molecular Formula, etc.
  • Automatically generate a mass value from MS data (when available).
  • Automatically generate Molecular Formula from MS data, and NMR spectral information.
  • Use DEPT-edited NMR spectra to automatically determine 13C multiplicity.
  • Create Good or Bad lists to provide the software with any structural knowledge that may be known prior to elucidation (i.e., include or exclude known structure fragments, functional groups, ring sizes, etc.).

Database Searching (Dereplication Stage)

  • Automatically search ACD/Structure Elucidator Suite's internal library of over 410,000 compounds from the spectral data provided, or search the included ChemSpider database.
  • If no structures are found in the initial database search, the software can search through its internal library of over 2,000,000 structural fragments. Any found structural fragments can be used in the ensuing elucidation process, or can be used for substructure searches in in-house or commercial libraries.

Structure Elucidation (Compound Generation Phase)

  • Generate a 2D connectivity map (Molecular Connectivity Diagram, MCD) and then draw in carbonyl, carboxyl, or other obvious features from IR knowledge or synthetic pathways. A MCD is a map of atoms and correlations between atoms that is automatically built by the software from 2D NMR spectral inputs, and used as a starting point for structure generation.
  • The MCD can be viewed and edited within the software. Different bond correlations are denoted in color.
  • The user can edit the MCDs to draw forbidden and obligatory bonds based on their own knowledge of the chemical structure and substance.

Structure Identification (Compound Evaluation Phase)

  • Following structure elucidation, the software compiles all possible structures based on the spectral, MF, and mass data provided, along with their correspondence with the proposed MCD.
  • View the generated structures in a tile, table, or one record mode.
  • Calculate the deviation statistic for each proposed structure. The deviation statistic is a value that determines agreement between the experimental 13C NMR data and predicted 13C NMR data. The lower the match, the better the correspondence the proposed structure has with the experimental data.
  • Sort the generated structures based on the deviation statistic to determine which compounds best match the experimental 1D and 2D NMR data provided.
  • Interactively select only the chemically relevant structures from the proposed list and create a new list of structures in Table or Tile mode. For example, a spectroscopist can browse all of the proposed structures provided by the software and quickly eliminate any structures that are irrelevant based on their biosynthetic pathways, etc.
  • Automatically remove any structures from consideration based on a deviation statistic threshold. A general rule of thumb is to reject any proposed structures with an average shift deviation of greater than 5.5 ppm. It is important to note that ranking structures with match factors less than 5.5 ppm should be done with extreme care and the user should evaluate the suggested fragments very carefully.
  • If proposed structures have several stereoisomers, the software can use NOESY and ROESY data to determine the relative stereochemistry of the proposed compounds.

Databasing Features

  • Update the database with the experimental spectra along with their chemical structures, analysis results (table of peaks, annotation), as well as any miscellaneous information you copied to the User Data and Notes.
  • Populate user databases with thousands of spectra in one step with the Group Macro batch processing tool.
  • Search by full spectrum or spectral region(s), peaks, spectral parameters, chemical structure and substructure, formula, molecular weight, and user data text.
  • Perform spectrum searches according to the Euclidean distance, or squared or absolute difference methods; the search hits will be ranked by HQI (Hit Quality Index).
  • Control data that is entered into your corporate databases with Data Forms Manager.
  • Manage remote databases through a local or global network with an Oracle-based SQL client-server system.