I cannot create a partition on free space, neither can I delete the extended partition.
Disk utility says
Cannot delete extended partition while logical partitions exist
Among those partitions created by you , find which one is logical partition and delete that partition.
PS: use Gparted instead of using Disk utility. Gparted is more featured than disk utility.
sudo apt-get install gparted
What you could do is enlarge the extended partition to include the free space, then create a new partition in the free space.
If, on the other hard you do not need the 2Gb NTFS logical partition, first delete this partition, then delete the extended partition. you will then be able to create a new partition for all the free space, including the one freed by the deletions.
/dev/sda
suggests that the partitions will be probably mounted.