MOLGEN MS

Markus Meringer
August 3, 2009

Evaluation of Low Resolution Electron Impact Mass Spectra without Database Search

The program system MOLGEN-MS is devoted to computer aided molecular structure elucidation. MOLGEN-MS is mainly adapted to low resolution electron impact mass spectra but also includes tools which allow to process high resolution data and results from atomic analysis. Even information gained from IR or NMR interpretation can be added. MOLGEN-MS arose from the idea to provide a database independent tool for molecular structure elucidation in both chemical industry, research and education.

MOLGEN-MS consists of the following main components

• MSclass (m ass s pectra class ification) predicts the presence or absence of substructures from low resolution mass spectra by multivariate classification methods. In the current version there exist 160 classifiers for 85 different substructures or more general structural properties.
• ElCoCo (el emental co mposition co mputation) computes candidates for the molecular formula by recognition of interleaving isotope pattern in low resolution mass spectra.
• Molin (mol gen in put converter) serves as interface between MSclass , ElCoCo and MOLGEN and allows user interaction during the elucidation process.
• MOLGEN (mol ecular structure gen erator) is able to compute in an efficient and redundancy free way all the connectivity-isomers that correspond to the molecular formulae proposed by strong>ElCoCo and which fulfill the substructure restrictions obtained from MSclass , prepared by Molin as graphical input.
• ReNeGe (re action ne twork ge nerator) constructs according to known ionisation- and fragmentation mechanisms the MS reaction networks for the structure candidates and investigates, how good the experimental spectrum can be fit by the theoretical isotope pattern of the virtual fragments.

MOLGEN-MS is available for Windows 9x / NT 4.0 / 2000 / XP / Vista.

Take a look at the MOLGEN-MS flowchart or in the online manual .

The module that matches structural formulas and mass spectra is also available as console application MOLGEN-MSF.

Current developments focus on processing high-resolution data from tandem MS and will be available as console application MOLGEN-MS/MS.