If it is a 5 year contract and he signs it before anybody else this year, it will be the largest contract in the history of the NBA. The last Jordan-Bulls year will be a higher one year salary, but Derozan's contract of 5/153 will be bigger than Kobe's contract he signed in the mid 00s by almost $20 million.
I also don't view this as a terrible contract for the Raptors, who else are they getting up there to take their money? If they aren't overpaying Derozan, they'll have to overpay somebody else.