Informix Older than 15 Minutes How can I do this MySQL statement in an IBM Informix?

select type, channel, teilnr, starttime, endtime, usedtime, host 
from online_time 
where starttime &lt; DATE_SUB(NOW(),INTERVAL 15 MINUTE)
order by starttime desc 


I tried this one in Informix, but it gave a syntax error. 

select type, channel, teilnr, starttime, endtime, usedtime, host 
from online_time 
where starttime &lt; subdate(CURRENT, INTERVAL "15" MINUTES)
order by starttime desc
SELECT type, channel, teilnr, starttime, endtime, usedtime, host 
FROM online_time 
WHERE starttime &gt; (CURRENT - 15 UNITS MINUTE) 
ORDER BY starttime DESC