i searched for the readme file that is made avaialbe in every patch extract but unable to find the same. Just go through the readme file and you would have an idea. they would have mentioned the dependencies if any.
I have had a call in to HP abut release date. This is the planned releate of V5.1.
My name is ******, I have been assigned to investigate your case.
Service Desk 5.1 is planned to be released by mid-August this year. Migration tools to upgrade from SD4.5 SP17 will be made available separately. Availability of these is planned for November this year.
Do not hesitate to contact me if you have any more questions on this subject.