2009/12/15 Noel O'Boyle <[email protected]>:
> 2009/12/14 Geoffrey Hutchison <[email protected]>:
>>> So I thought about changing the fragment to be composed of C atoms and
>>> using that to derive the canonical representation.
>>
>> The problem is that if you change the fragment to C atoms, you have lots of 
>> un-filled valence. Consider, changing the "N" in pyrrole (or S in thiophene) 
>> to carbon. It's no longer aromatic. So with that approach (making fragments, 
>> changing atoms to carbon, writing output), the resulting SMARTS patterns 
>> weren't
>
> Got you.
>
>> I see your point. Perhaps the "best" solution is to look for similar SMARTS 
>> in the post-processing step and merge them?
>
> Aha, finally a use for canonical SMARTS strings! Which I'm afraid we
> don't have. But I might be able to identify at least the simpler
> duplicates.

Actually just thought of a way to create canonical SMARTS string.
Craig, do you have code for generating all possible SMILES strings for
a particular molecule? If so, then I could do this for each fragment,
do string replacement to create the corresponding SMARTS, and pick the
'canonical SMARTS' with the lowest alphabetical order.

>> Craig, do you have another solution? Is there a wild-card or dummy atom for 
>> the canonical SMILES?
>>
>> -Geoff
>

------------------------------------------------------------------------------
Return on Information:
Google Enterprise Search pays you back
Get the facts.
http://p.sf.net/sfu/google-dev2dev
_______________________________________________
OpenBabel-Devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/openbabel-devel

Reply via email to