Volume 2 Chapter 2 2D-Constrain Sub-menu SAME-RESIDUE

Function

SAME-RESIDUE is used only when the search fragment consists of more than one sub-fragment which must be different from each other or when you have used NUMBER-OF-FRAGS to require multiple occurrences of your fragment.

It is used to specify that all the sub-fragments must occur in the same residue for a hit to be registered.

Examples

Ex. 1 Suppose we have built the fragment (i) - see below.

Select SAME-RESIDUE

Select a MENU command. or select an ATOM or BOND to display its
properties.

Select DEFINE-STRUCTURE
A search would register a hit for (ii) but not for (iii).

You should note that if the fragment contains only one residue then:
Select SAME-RESIDUE

Only ONE residue present, so this command is meaningless.
Please press <RETURN> to continue. Thank you.

Note also that if you change your mind and do not wish to use the SAME-RESIDUE constraint, then simply re-selecting the SAME-RESIDUE command will deactivate it - the red box around the command vanishes.

Ex. 2 Suppose we have constructed the fragment (i) - see below. It contains two residues - the carboxylic acid group and the nitro group.

(i)

Suppose we wish to find compounds where these 2 groups occur in different residues.

The procedure would be as follows:

Having built the fragment (i)

Select DEFINE-STRUCTURE
This defines test 1.
The BUILD menu is restored.
Select 2D-CONSTRAIN
Select SAME-RESIDUE
Select DEFINE-STRUCTURE
This defines test 2

A search of the type TI .NOT. T2 will produce the desired hits eg. (ii) but not (iii).

(ii)

(iii)

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Volume 2 Chapter 2 2D-Constrain Sub-menu SIMIL .