Delta has a 50% bonus on transferring AmEx MR points, so you can get a biz class for 80K MR points (120K Delta miles).
http://thepointsguy.com/2011/07/whic...ways-or-delta/
Delta no longer flies nonstop to BOM, but they do have options with via Amsterdam and Paris with KLM and Air France. They also partner with Jet on the JFK-BRU-BOM route, though that availability is scarce (you have to call Delta to check it). Delta will cost 80,000 miles in coach or 120,000 business class.
You have to be super flexible to do this though because Delta has a reputation for not much availability at the lowest mileage tiers.