I am trying to use a pattern-list match in korn shell using a variable and it always seems to regard the pattern-list as a literal:

Using the directory names explicitly in the pattern-list works fine:
ls @(test|test1)/test.txt

and returns:
test/test.txt

Trying to use a variable for this purpose fails:
export patternList=test\|test1
ls @(${patternList})/text.txt

and returns:
@(test|test1)/text.txt: No such file or directory

I tried to interpret the way paths are dealt with in the ksh man page, but failed to understand it properly which is probably why I don't understand why this doesn't work. Can someone tell me how to make this work or why it does not work?