Robert L. Moore, Co-Founder of Sheraton Corp.

Robert Lowell Moore, co-founder of the Sheraton Corp. hotel chain, has died at age 90.

Moore, who died Wednesday, began buying depressed real estate, including two hotels, in 1934 with his Harvard University roommate Ernest Henderson.

A third hotel, the Sheraton in Boston, was bought for back taxes owed the city. Because of the large electric sign on the roof advertising the hotel, the pair took its name for future sites.

The chain, based on reviving failing hotels, prospered during the early days of World War II.

In 1944, the two bought Boston’s Copley Plaza, made it their flagship, and continued building the Sheraton chain. In 1948, they merged with U.S. Realty & Improvement Corp., and the companies became Sheraton Corp. of America.

In 1967, Moore and Henderson began negotiations with International Telephone & Telegraph Corp., which bought Sheraton in 1968. Henderson died during the negotiations.