Markus Sitzmann [ Editor ]
The kete-enol and 1,5 tautomerism features were only finished after version 1 of InChI was released (if I remember correctly, they only became available with version 1.03, i.e. the latest release of InChI). And as far as I know, the InChI people regard “switching them on by default” would require a jump to version 2 of InChI (as too many things would be affected by this) … and so far everybody seems to be hesitant about this – I think that is all (maybe they also wait for more feedback until they make the big jump to version 2 or wait for other features to get ready). Since InChI handles this kind of tautomersim in ring systems already in many cases correctly the pressure doesn’t seem to be too high.