A Benefit auction for the Child Mind Institute offered works by Richard Prince, Jeff Koons and Nate Lowman on Thursday and raised a record-breaking $2 million for the nonprofit. Generating particularly heated bidding at the Sotheby’s auction was Lowman’s “Fleshtone,” which easily topped its pre-auction estimate of $95,000 by selling for $235,000. An untitled Prince work went for $175,000, and Urs Fischer’s “Paranoia/Squirrel” had bidders going nuts, drawing the event’s top bid of $360,000. Hosts were Peter Brant and Stephanie Seymour, and Daniel and Brooke Garber Neidich, with guests Vito Schnabel, Larry Gagosian, John McEnroe, Aby Rosen, Dori Cooperman and Jessica Hart.