bash error

hi all,

i am trying to take backup of oracle tables by using exp command but when i am entering the command it is giving a error as below
bash: syntax error near unexpected token `('

So kindly someone tell me how to rectify this and proceed for the normal export.

The original command what iam typing is

exp username/password@sid file=filename.dmp log=filename.log tables=(all table names separated by comma) indexes=n grants=n direct=true