(D1 AND A9) OR D23
Place parantheses around building block names. In this example, results must contain either BOTH D1 and A9, OR it must contain D123.
(NOT[D23] AND A9)
Use the NOT keyword with the square brackets to exclude a building block. In this example, results must NOT contain the D23 building block AND must contain the A9 building block.
(D* AND R*)
Use the asterisk as a wildcard. In this example, results must contain at least one building block starting with D AND at least one building block starting with R.
(R1*-D3 AND NOT[R10-D3]) OR (R3-A2 AND NOT[Sp*])
The dash represents a functional group-building block pair. R3-A2 will look specifically for the building block A2 with R3 attached to it. Combine the wildcard, NOT keyword and parentheses to build a complex query.
NOTE: The NOT bracket placement is important! When the brackets surround an entire functional group-building block pair, it means that pair MUST NOT appear in the result.
ONLY(D20 AND A48)
Find structures with only two building blocks, D20 and A48. No other building blocks allowed. You can combine multiple building blocks using ONLY as the first keyword to find results containing only the listed building blocks.
NOTE: ONLY cannot be combined with NOT's or OR's. Only ANDs can be used with ONLY.
R*-A* AND NOT[R*]-D*
This example shows a different placement of the NOT brackets. In this example, we will match results that have at least one DONOR with no R and also have at least one ACCEPTOR with an R.
*Note the placement of the brackets[] around the functional group only. This means we are looking for D1 building blocks that do not have an R functional group attached.
