Hello,
If you are running version 8.3 or above, you can apply the following commands:
object network obj-10.1.1.2.34
host 10.1.1.2
nat (Inside,Outside) static 15.15.15.15 service tcp 34 34 nds:
object network obj.10.1.1.2.443
host 10.1.1.2
nat (Inside,Outside) static 15.15.15.16 service tcp 443 443
If you are running version 8.2 or less, you will need to apply the following commands:
static (Inside,Outside) tcp 15.15.15.15 34 10.1.1.2 34
static (Inside,Outside) tcp 15.15.15.16 443 10.1.1.2 443
Let me know how it goes.