This is as much as I have learned so far (from the anime ofcourse, I dont read the manga)

Teacher -> Student


1st + 2nd -> 3rd
3rd -> Orochi / Tsunade / Jiraiya
Orochi -> Anko
Jiraiya -> 4th (and now Naruto)
4th -> Kakashi
Kakashi -> Naruto / Sasuke / Sakura
Kurenai -> Kiba / Hinata / Shino
Gai -> Lee / Neji / Tenten
Asuma -> Ino / Chouji / Shika
Ebisu -> Konohamaru (and Naruto for a couple of minutes)


Did I miss anything or figured things wrong?