Chevron Corp. is negotiating to purchase the 1400 Smith tower in downtown Houston for a reported $380 million. The 50-story, 1.3 million-sf building will be listed for sale with HFF if Chevron does not purchase the tower, according to Real Estate Alert. The building, known as Four Allen Center, is currently owned by Brookfield Office Properties. Chevron leases Four Allen Center, which was formerly the headquarters of Enron Corp. The Chevron deal would be one of the biggest sales ever in Houston real estate. Last fall, Brookfield purchased the 53-story, 1.2 million sf Heritage Plaza for $325 million or $285 per sf.