SQL & PL/SQL

I wonder if anyone can help I am running some sql to see if a date is greater than another date.

I am in the process of migrating mysql to oracle, several mysql functions in oracle dont exist by the same name if at all in oracle. So I have written some PLSQL routines which are working as expected.

SQL> select now from dual;

NOW
--------------------------------------------------------------------------------
18-MAR-2003 13:03:19

SQL> SELECT * FROM (SELECT (DATE_ADD(DATESET, 'INTERVAL 30 DAY')) TIMETOCHANGE FROM PASSWORDHISTORY
WHERE USER_ID = 36) WHERE ROWNUM < 2;

TIMETOCHANGE
-----------------------
14-SEP-2001 00:00:00

However when I run

SQL> SELECT * FROM (SELECT (NOW() >= DATE_ADD(DATESET, 'INTERVAL 30 DAY')) TIMETOCHANGE FROM PASSWOR
DHISTORY WHERE USER_ID = 36 ORDER BY DATESET DESC ) WHERE ROWNUM < 2
2 ;
SELECT * FROM (SELECT (NOW() >= DATE_ADD(DATESET, 'INTERVAL 30 DAY')) TIMETOCHANGE FROM PASSWORDHIST
*
ERROR at line 1:
ORA-00907: missing right parenthesis

Its not clear above where the * is, because of the formatting of this page it comes below ">=" any ideas?

Thanks