Shell scripts

I cant get a shell script to work. This one is supposed to execute
r.in.ascii for several hundred files

#!/bin/sh
for FILENAME in 'ls /u1/copeland/rams3a/van/*00'
do
r.in.ascii input=/u1/copeland/rams3a/van/$FILENAME output=$FILENAME
done

when executed I get the following error message
_____________________________
Sorry </u1/copeland/rams3a/van/PTOTAL-07-15-00> is not a valid option

Looks like you're using forward ticks ' instead of back ticks `,
so for is treating ls and /u1/... as members of a list.