Rothko’s hot-hued “White Center (Yellow, Pink and Lavender on Rose),” from seller David Rockefeller Sr., and Bacon’s fierce crouching Pope, “Study From Innocent X,” helped propel the 74- lot auction at Sotheby’s to a record $254.9 million. Before tonight, the highest auction price for an artwork from the period was a $27.1 million Willem de Kooning in November.