Using R-group queries

ChemAxon 990acf0dec

23-08-2010 11:08:58

This question came through email:


"For a specific atom in a ring  I want to
define a list
containing O, S, and the NH, CH2 groups.


Up to now, I could build lists containing
only atoms. How
can I mix atoms and the NH and CH2 groups in one list?"


 


Answer:


You can use R-group query for this purpose, where the substituent list contains O, S, N, and C, plus you either draw the explicit Hs on the N and C atoms (see the attached file), or use the "Total number of attached hydrogens" or the "Substitution count" query options. For more details on how to draw R-group queries and how to use Query Properties, please read these pages:


- https://www.chemaxon.com/marvin/help/sketch/sketch-basic.html#howto-draw.rgroups


- https://www.chemaxon.com/jchem/doc/user/query_features.html#atprop


You can also use SMARTS if you are familiar with it; in this case you don't have to use R-groups, you can replace the atom with the SMARTS, and it gives back the same hits. If you are interested in how to create such a SMARTS, please let me know. For more details on SMARTS notation please read this doc:


https://www.chemaxon.com/marvin/help/formats/smiles-doc.html#SMARTS


 


Best regards,


Akos