Good evening,
I am trying to convert a standard InChI string to a non-standard InChI string with fixed-hydrogen-layer:
Example:
Standard inChI for Uracil:
InChI=1S/C4H4N2O2/c7-3-1-2-5-4(8)6-3/h1-2H,(H2,5,6,7,8)
Desired outcome:
InChI=1/C4H4N2O2/c7-3-1-2-5-4(8)6-3/h1-2H,(H2,5,6,7,8)/f/h5-6H
InChIkey for Uracil: ISAKRJDGNUQOIC-UHFFFAOYSA-N
My question is if this is at all theoretically possible without further information and if not, are there other ways to achieve this goal, e.g. using an existing database?
The ultimate goal is to convert the InChI string with hydrogen layer into a mol file to be able to map chromatogram peaks against it, so I installed OpenBabel which can do the trick, but it can not solve the aforementioned conversion between the InChIs.
I already found the cactus website which allows to convert from InChIkey (which I can generate from the standard InChI that I have) to the desired non-standard InChI (with hydrogen layer) via inserting the InChIkey into the url like so: http://cactus.nci.nih.gov/chemical/structure/ISAKRJDGNUQOIC-UHFFFAOYSA-N/inchi. The problem here is that it returns multiple correct non-standard InChI strings (with fixed hydrogen layer). One of them is the standard for uracil that I am after but I don't see a way to figure out how to pick the correct one automatically. As you can imagine I want to run this in an automated fashion for hundreds of conversions.
I appreciate your help.
Loddi
