THE RING OF CHEVRON Today’s the day Chevron is expected to close on the purchase of the 50-story former Enron headquarters building it’s already leasing at 1400 Smith St. downtown, which the oil company is buying from Brookfield Office Properties for an estimated $380 million. Already in Chevron’s hands: the second, César Pelli-designed Enron building at 1500 Louisiana, the parking lot and small building across the street from it. The company still plans to buy the lot down the street at 1600 Louisiana at the end of this year, once the YMCA finishes tearing down its building there. [Houston Chronicle; previously on Swamplot] Photo: Jonathan McIntosh [license]