1st: Doc Ock, Kraven, Mysterio, sandman, Vulture and Electro: ASM Annual # 1, basically the six figured that if they worked together they could beat spidey, except that they decide to wekaen him slowley by going at him one at a time. Vulture actually objects to this idea.
2nd: Doc Ock, Mysterio, Sandman, Vulture, Electro, Hobgoblin II:ASM # 334-339, don't exactly know what they did, never read it. I just know that by the end evry member pretty much hated Doc ock.
3rd: Doc ock, Mysterio, Vulture, Electro, Hob II, and Gog: SM # 18-23, Basically the villains work togther to open a riff in dimmensions so they can gain weapons to take over the world. There are a plethora of guest stars, icluding the Hulk, and the FF. Plus, Spidey get's turned into a cyborg, yeah 90's.
4th: Sinister Seven: Electro, Mysterio, Shocker, Vulture, Hobgoblin, Beetle, Scorpia: Spider-Man Unlimited # 9: as far as i remember all these villains teamed up to defat Kaine, because he was attempting to kill most of Spidey's rogues gallery.
5th: Mysterio, Vulture, Sandman, Kraven II, Electro, Venom: Asm Vol. 2 # 12, and SM Vol. 2 # 12, it had something to do with something that Mackie and co had thought up that had to do with nothing: it involved Senator Ward, which is spidey language for don't even bother reading it.
and that's leads us up to their appearance in MKSM.