import re

pattern = "(?:\\b[Tt]o:|\b002;)\s*(.+?)\s*<[^<>@]+@[^<>@]+>"
mystring = 'To: John Lennon <John.Lennon@gmail.com> \b002; Paul McCartney <Paul.McCartney@yahoo.com> \b002;'
print(re.findall(pattern, mystring))