The Braintree-based Flatley Co. has pared numerous properties in recent years, including several significant sales in 2007. That activity was headlined by a $500 million dispatch of 10 New England retail assets, but a Marriott Hotel at the developer's Crown Colony Office Park in Quincy also changed hands for $116 million in May, and Flatley also this spring harvested a 10-building portfolio on the South Shore for $52 million. On the other side of the aisle, GlobeSt.com last week reported that Flatley has agreed to buy another real estate property, the 700,000-sf Hewlett-Packard corporate campus in Nashua, NH for more than $45 million. Calls to Flatley to discuss that deal and the Boston sales were not returned.

Synergy, meanwhile, has been in an aggressive acquisitions mode this year, not only buying the Flatley assets, but also announcing today the purchase of 133 Portland St. in Boston's North Station market. After being acquired in North Station's dark ages of 1995 for less than $50 per sf, 133 Portland St. fetched four times that amount in a $6 million sale by Edgewood Capital Advisors. According to participants in the transaction, the upside reflects the office submarket's revival following the Big Dig project, plus a growing ardor for Class B buildings to take advantage of a suddenly resurgent office market. The Big Dig project depressed not only the hulking Central Artery, but also an elevated trolley line that for decades had cast shadows upon North Station, including Portland St.

Calling 133 Portland St., "a solid acquisition in an emerging district," Synergy VP Dee Minnock adds that the six-story, 30,000-sf building "will complement our ownership of other assets within the Bulfinch Triangle," referring to a section of the district known for its historic buildings and unique architecture. Synergy last year bought 141 Portland St., a 23,000-sf office/retail building secured in an equity deal with Irish and US investors. Investors also sent cash from Ireland to participate in the latest trio of sales, Synergy indicates.

Among the assets Synergy has secured in the city are 211 Congress St., in the Financial District, as well as 43 Winter St. in the Downtown Crossing market and the nearby 26 West St., a 56,000-sf office/retail property. Founded by investor David Greaney in 2004, Synergy has been especially active this year, buying 10 Fawcett St. in Cambridge's Alewife District in January, and paying $34 million this spring for a mixed-use complex in Dorchester featuring 42,000-sf of office space and a 60,000-sf supermarket.

While Synergy predicts 133 Portland St. will prove to be a solid investment, the sellers garnered a substantial gain from the $1.45 million paid for the building in 1995. The investment was made through the Millwood VII LP, a limited partnership that actually existed before partner Thomas McDevitt formed Edgewood in 2002. The CRE investment firm is headquartered in Southport, CT.

Grubb & Ellis of Boston orchestrated the sale of 133 Portland St. G&E VP Noah Hano calls the asset "a well-located building sure to benefit from Synergy's vision and expertise." A member of the investment sales team, Hano was joined in brokering the deal by VP Anthony Biette and SVP Karyn McFarland. According to G&E's research department, the North Station office district has 3.9 million sf and a vacancy rate of 7.7%. That is better than the overall city average of 9.3%, even though net absorption for North Station was negative 22,000-sf in the second quarter and is positive by just 2,500-sf for the year, according to G&E.