ACD/Structure Elucidator

What's New

NOTE: Please refer to What's New in ACD/1D NMR Processor, ACD/2D NMR Processor, ACD/1D NMR Manager, ACD/2D NMR Manager, ACD/HNMR Predictor, ACD/CNMR Predictor, ACD/ChromManager, ACD/UV-IR Manager, and ACD/MS Manager as these products are included when purchasing ACD/Structure Elucidator.

Version 10.0 to 11.0

• Manually include known fragments to Molecular Connectivity Diagram (MCD)
• Improved referencing for 2D NMR spectra
• Automatic solvent detection
• Improved gridline management
• New screen layouts
• Create 1D NMR spectra from experimental 2D datasets
• Improved structure generation algorithm
  • Faster and more accurate structure generation
• Use prediction training databases in elucidation

Download a PDF copy of the expanded details on What's New with ACD/Structure Elucidator, or contact your Account Manager or Distributor.

Version 9.0 to 10.0

Now Includes

• ACD/2D NMR Predictor and ACD/ChromManager.

Ease of use

• View and manipulate experimental data within the Structure Elucidator interface.

Analysis

• Improvements in the automated peak picking algorithm to provide faster preparation of data.
• Molecular Connectivity Diagrams (MCDs) are now created in real-time as the data is being imported and edited.

Visualization

• Visualized verification of elucidation results-color-coded cues that highlight the area of ambiguity in a proposed structure.

Version 8.0 to 9.0

Analysis

• Solve the relative stereochemistry of chemical structures when NOESY or ROESY data is imported.
• View 3D structures and NOESY and ROESY through space correlations in the ACD/Structure Elucidator interface.
• Apply Indirect Covariance conversion to processed spectra.

Databasing

• Search ¹H chemical shifts in the internal database.
• Interactively select only the chemically relevant structures from the proposed list and create a new list of structures in Table or Tile mode.
• Speed of CNMR database search has increased dramatically (>10 times faster).
• Significant improvements in both automated and manual 2D NMR peak picking.

Version 7.0 to 8.0

Algorithm

• Number of allowed non-standard correlations increased in the CSB Generator:
  • Any number of non-standard correlations and option to specify a spectrum containing these correlations.
• Restrict the number of generated structures and/or generation time in the CSB Generator.
• Allow filter options during Standard Generation.

Databasing

• Enhanced searching by spectrum by using all spectral information such as information from 2D NMR (distance between carbon atoms and chemical shifts of attached hydrogen).
• Proton chemical shifts have been added to the internal database.
• Enhanced molecular formula generator:
  • Generate MF from charged structures and M+H ion.
• Additional filter options:
  • Filter by number of exchangeable protons and occurrences of structure fragments.
• Automatically select optimal parameters to include the user-defined fragment in the MCD.
• Application of MCD properties to other MCDs.
• Search of structures by match factor.

Analysis

• Use multiplicity edited spectra to determine carbon multiplicity.
• Command line enhancements:
  • Integration with JEOL. Added solvent detection, set axes tolerance, set intensity threshold, and process and generation time restriction.
• Validation of data procedure:
  • Check existence of and correspondence between all important data.
• Include/exclude peaks conveniently.
• Import structure data from ACD/SpecManager:
  • Transfer partial and complete assignments to Structure Elucidator.
  • Import multiplet information.
  • Transfer labeled peaks from IR spectra to Structure Elucidator.
• Edit MCD correlations.
• Draw ambiguous correlations.
• Display correlation direction.

Ease of use

• Elucidate your structure with step-by-step help from the improved Elucidation Wizard:
  • Add structures directly from the wizard.
• Run automatically from NMR spectrometer output:
  • Integration with JEOL. Add solvent detection, set axes tolerance, set intensity threshold, and restrict process and generation time.

Version 6.0 to 7.0

Algorithm

• Recognize the ⁴J correlations:
  • Structure generator will allow you to manually assign 4 bond couplings to a 2D spectrum.
• Use "fuzzy" generation for couplings that are ambiguous.
• Set a maximum correlation length for Molecular Connectivity Diagrams (MCDs).
• Specify the acceptable ring sizes:
  • Filter structures by allowing certain ring sizes and forbidding others.
• Remove chemically unreasonable structures from list.

Ease of Use

• Elucidation Wizard:
  • Elucidate your structure with step-by-step help from the Elucidation Wizard.
• Command Line:
  • Run the main elucidation stages and the auto elucidation process through the command line.

Analysis

• Use the hydrogen chemical shifts in the structure generation procedure:
  • This can help reduce the number of potential structures.
• Use HSQC-TOCSY spectra to aid in elucidation:
  • The positive or negative response from the experimental spectrum can indicate either direct or long-range coupling.
• Solve for structures with up to 249 heavy atoms or 10000 Daltons.
• Automatically remove duplicated structures during the generation process.

Input/Output

• Extract 1D information from a 2D spectrum:
  • Create correct 1D ¹³C spectra from projections of 2D NMR data.
• Determine the multiplicity of peaks in a 1D carbon spectrum:
  • Specify input spectra such as DEPT.
  • Determine the number of attached hydrogen atoms.

Display

• View connectivities from different spectra independently:
  • The display of the Molecular Connectivity Diagram (MCD) is customizable.
• View correlations from a 2D NMR spectrum in a generated structure:
  • Molecular view simplifies the filtering of unreasonable structures.
• Forbid a bond between atoms.

Visualization

• Substructures are highlighted when found during a substructure search.
• View the difference between experimental and calculated shifts with color:
  • Easily distinguish good from bad matches.
  • Useful when a few individual atom differences are high but overall the structure is a good match.

Advanced Tools

• Generate a structure with any element:
  • Specify the valency where appropriate.
• Launch the 3D structure viewer for generated structures directly from Structure Elucidator.
• Search for multiple substructures simultaneously from the ChemSketch window.
• Use several databases (CNMR, HNMR, XNMR, etc.) in the spectral calculation.
• Split or combine chemical shifts because of symmetry.
  • Symmetry is important to the elucidation procedure.
  • In some cases, symmetrical atoms will have different chemical shifts.
  • In other cases, magnetically non-equivalent atoms will have identical chemical shifts.