Passing pattern in Ensemble function

Hello,

I am trying to pass a pattern in the Ensemble function Matches(val,pat) in Business Rule as below.

Eg. 

Matches(tSite, " 1(.E1 "SITE A ",.E1 "SITE B ") ")

tSite is a variable containing the site name

Want to check if the variable contains any of the site name.

But i receive a parsing error when compiling.

Is there another way to pass the pattern in the Matches function or any other similar function which i can use in the business rule or DTL without multiple sentences with Contains.

Thanks,

Jimmy Christian.