This problem occurs when the -global_opt option is turned on during MAP. It appears that invalid characters are written to the physical constraints file (.pcf) at the end of MAP.
This issue will not be fixed as the -global_opt option is being deprecated and will not be available to use for the newer devices or next generation tools.
The following options can be used as possible workarounds:
In the above mentioned error message, the line number with the syntax error is line 287.
For example, if the syntax error happens to occur due to the following line in the PCF file,
TIMEGRP &B K = BEL ....
Correct the TIMEGRP name to work around the issue.
Some occurrences of this issue have been fixed in ISE 14.1 Design Suite. It was found that this did not fix all cases and so another bug fix has been made for ISE 14.4 Design Suite.