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CYCLICITY

CYCLICITY is used to specify that an atom or bond must be:

part of a ring (CYCLIC)

or

part of a chain (ACYCLIC)

Suppose we wish to search for cyclic thioketones.

Suppose we have built the fragment:

• Select CYCLICITY

  C appears in the CYCLICITY box.

• Select ATOM or BOND for CYCLICITY specification.
  Re-select CYCLICITY to toggle A and C.
  (Select another command to end CYCLICITY)

• Select in turn each of the C - C bonds

The fragment is now:

Note the following:

If a bond is specified as

• cyclic then C is displayed on the bond

• acyclic then A is displayed on the bond.

acyclic then it is displayed as eg. CA.

The CYCLICITY command toggles with respect to 3 settings:

• CYCLIC
• ACYCLIC
• UNSPECIFIED

Suppose we have the fragment:

• Select CYCLICITY

  C appears in the CYCLICITY box.

• Select ATOM or BOND for CYCLICITY specification.
  Re-select CYCLICITY to toggle A and C.
  (Select another command to end CYCLICITY)

• Select CYCLICITY

  A appears in the CYCLICITY box.

• Select ATOM or BOND for CYCLICITY specification.
  Re-select CYCLICITY to toggle A and C.
  (Select another command to end CYCLICITY)
  

• Select N atom

  The fragment is now:

  

• Select CYCLICITY

  U appears in the CYCLICITY box.

• Select ATOM or BOND for CYCLICITY specification.
  Re-select CYCLICITY to toggle A and C.
  (Select another command to end CYCLICITY)

• Select N atom

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Volume 2 Chapter 2 2D-Constrain Sub-menu DEFINE-STRUCTURE.