One of Boston's most active office investors has acquired another tower in one of the largest deals since the pandemic.

Synergy acquired the 32-story office tower at 99 High St. for $227M from Nuveen, property records show. The sale represents a 17% discount from the $273M Nuveen bought it for in 2005.

"We love the asset, it's in a phenomenal location and we love the basis," Synergy Head of Investments Matthew Godoff told Bisnow.

The 730K SF property is 78% leased with tenants including Mercer, Marsh McLennan, AIG and Karuna Therapeutics, Synergy said in a release.

Godoff said the firm is happy with the leasing demand in the building and plans to attract more tenants with a planned amenity center to be built out in the first quarter of 2026.

The company is assuming the mortgage on the property from MetLife, who was willing to modify the existing debt on the building as part of the deal. The building went up for sale last year with Newmark as the broker.

Founded in 2003 by CEO David Greaney, Synergy likes to buy when prices are low. It ramped up its acquisition activity after the Great Financial Crisis in 2008, and it has closed a series of big office deals since the pandemic.

Greaney said in the release this deal "solidifies Synergy’s prominence as one of Downtown Boston’s premier owners and operators."

“Synergy will continue to invest in high-quality assets in prime locations across the city," he said.

Last year, Synergy acquired 101 Arch St., a 21-story, 407k SF office building, from Clarion Partners for $78M, marking the largest postpandemic office sale in Boston at the time. The only office sale larger than Synergy's latest deal was when One Lincoln sold back to its lender for $400M last month.

Synergy's other acquisitions over the last three years include 197 Lincoln St., One Liberty and One India.

"We're actively looking for other opportunities, and we believe in downtown Boston and well-located high-end assets," Godoff said.

The office building was built in 1971 and underwent an extensive lobby renovation in 2019. The office has also seen more than $24M in capital improvements over the past decade.