As we have discussed here before, Munich is an extraordinarily efficient airport. Even when things are really bad I wouldn't expect immigration (you need a Schengen visa to go to Munich btw) to take more than 30 minutes, typically less than ten. So by all means you will be out in less than an hour, with a little luck it can be as little as 30 minutes (I presume your luggage is through checked). It's an hour to Connollystraße by S1 and U3, another to get back. I would plan to get back to the airport 90 minutes before to make it safe. I would expect you will have about 1.5 hours at Connollystraße.
Edit: to roll some of the comments into the answer, yes, the old Terminal 1 is not so great but I readily presumed OP is flying Delhi-Munich direct which means they are flying on Lufthansa because at this time the only direct flight between the two is LH763 (arriving 5:25AM) and so they will use Terminal 2. (Even if Air India starts a flight, this will still be true because all *A airlines except TK are in T2). However, when I look at the Munich-New York flights -- there are not many -- all of them are from Terminal 2: United at 9:30AM, Lufthansa at 12:25PM and 4:05PM. Either OP has seven hours or one of the legs is not direct.