Hello

was wondering if someone can help me with SMARTS string based substructure search?.

I have generated some structures (macrolides) and now I have their SMARTS string for e.g.

I have a 18-ring macrolide (Fig 1)

Whose SMARTS is

[#6]-1-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-[#6]-1

And corresponding SMILES is

C1CCCCCCCCCCCCCCCCC1

Now I am using this to do a substructure search on my another database and pulling out all the molecules with this matching SMARTS string.

Its working fine but along with the matching 18-ring macrolides I am also pulling out some structures that are like this (Fig 2):

(with SMARTS:

[#6]-1-[#6]-2-[#6](-[#6]-[#6]-[#6]-1)-[#6]-[#6]-[#6]-3-[#6]-2-[#6]-[#6]-[#6]-4-[#6]-3-[#6]-[#6]-[#6]-[#6]-4

(with SMILES:

C1C2C(CCC1)CCC3C2CCC4C3CCCC4

This is something that I do not want. ANy suggestion in how can I modify the searched SMARTS so that I keep such molecules out?

Thanxs

narender