imac-alexey-vyskubov:~ alexey$ cat file.1 
No
match
in
this
file
imac-alexey-vyskubov:~ alexey$ cat file.2 
DESC foobar
DESC barfoo
imac-alexey-vyskubov:~ alexey$ grep -F "$(grep -m1 -A1 DESC file.1 | tail -1)" file.2 > file.3
imac-alexey-vyskubov:~ alexey$ cat file.3
DESC foobar
DESC barfoo