Duplicates which probably not a duplicates

Greetings

We have a problem with one structure. IJC found it as a duplicate.

I`ve attached a simpler case. Why they are recognized as duplicates?

Best regards

Rafal

Dear Rafal,

these molecules might be considered as duplicates if you are using tautomer search. For more details on tautomer search please look into the JChem documentation.

Best regards,

Karla

Thank you for reply