Not my fav pick of airlines I must say (haven't flown them in years), but when you can get a business class return ticket to Singapore at just... 1,299 Euro... can you really complain?
The normal price is around 3-4k Euro. Only problem it's just for FRA-SIN, so (like me) you might need to buy a separate econ ticket to get to FRA from elsewhere in Europe.
I think the travel dates have to be between June and October, min. 5 days' stay. Might be some more conditions, but when you try to book and the 1,299 price shows up then you know you're fine.
P.S. The fare also accrues air miles at the standard business class rate (200%).