# OEEnumerateTautomers¶

OESystem::OEIterBase<OEChem::OEMolBase> *
OEEnumerateTautomers(const OEChem::OEMolBase &mol,
const OETautomerOptions &tautomerOptions)

OESystem::OEIterBase<OEChem::OEMolBase> *
OEEnumerateTautomers(const OEChem::OEMCMolBase &mol,
const OETautomerOptions &tautomerOptions)


This function takes a const input molecule that is to be tautomerized and the tautomers are returned as an OESystem::OEIterBase<OEChem::OEMolBase> *. Options are set with an OETautomerOptions. See the corresponding documentation for descriptions of options. The following code demonstrates how to tautomerize a molecule using options.

unsigned int OEEnumerateTautomers(OEChem::OEMolBase &mol,
OEMolFunctionBase &mfb, unsigned int allflag=0,
bool ch3flag=false
bool saveStereo = false, float maxTime = 120)


Warning

This version of OEEnumerateTautomers is deprecated. Use the above OETautomerOptions version above instead.

This function has four arguments. The first argument in a non-const molecule that will be the basis for the tautomer enumeration. For details of the enumeration process, please see tautomers. The second argument is a functor call-back. The functor’s operator() is called with each new tautomer state enumerated. The enumeration will continue until the functor returns false or until the enumeration is complete. The third argument is an unsigned int which indicates the maximum acceptable energetic category of enumerated tautomers. The function will return all categories of tautomers from the lowest available up to this cutoff. If the only available level is higher than the cutoff, that single level of tautomers will be enumerated. This control is in addition to the call-back control. Finally, the bool ch3flag argument controls whether tautomer enumeration should include tautomerization of methyl and methylene groups adjacent to a conjugated system. This allows cyclohexa-2,4-dien-1-one, O=C1CC=CC=C1, to be canonicalized as a tautomer of phenol, Oc1ccccc1. Unfortunately, the combinatorial explosion from tautomerizing across the alpha carbon of amino acids means that this option should not be used when enumerating the tautomers of proteins and large peptides. This function returns the total number of tautomers enumerated.

A setting of saveStereo=true will prevent associated atoms or bonds from taking part in tautomerization if they have stereochemistry set. Stereochemistry can naturally be lost with the creation and removal of double bonds.