I have a feeling you didn't do proper introductions with these cats, but may just brought the kitten in and expected your cat to accept him?
Your cat is feeling invaded and is being territorial, and I find female cats to be even worse in that department than males!
Introductions can make or break the whole relationship! You are going to have to start from the beginning with these two.
Here is a good article on properly introducing a new cat. Be patient - because now you are starting with two cats who already have a bad thing going on, and this could take quite awhile.
Get the kitten isolated in a room right away - the stress he is having from the constant attacks can result in bad behavior or illness on his part.