Rounding Pandas Timestamp to minutes

I want to create a DateTimeIndex at 1 minute intervals based on a start and end timestamp (given in microseconds since epoch) with pd_date_range(). To do this, I need to round the starting timestamp up and the ending timestamp down. Here is what I have so far:

import pandas as pdstart = 1406507532491431end = 1406535228420914start_ts = pd.to_datetime(start, unit='us') # Timestamp('2014-07-28 00:32:12.491431')end_ts = pd.to_datetime(end, unit='us') # Timestamp('2014-07-28 08:13:48.420914')

I want to round:

start_ts to Timestamp('2014-07-28 00:32') and

end_ts to Timestamp('2014-07-28 08:14').

How can I do this?