draining battery?

got a 06 m35 with uas installed.
got a brand new battery and let my car sit for a week or so and my battery died. 

any ideas of what caused this? could something be draining it?

what kind of battery? how many compressors do you have? compressors put a large strain on your battery.

yellow optima. 2 480 compressors. what caused it to drain if i  didnt drive my car for like a week?

my 480s drained my yellow tops very quickly to the point the batteries wouldnt charge up again. it makes the voltage dip very low for quite a while, which ends up killing the battery. you may want to disconnect the ground and use a battery tender/charger when the car isnt being driven and also look into getting a more powerful alternator and/or second battery with a battery isolator to run accessories. correcting any leaks (if you have any) will also help in that your compressors will be used less often and cause less drain on your electrical system.

are the compressors hooked up to a relay?
i suggest a PAC-80