Gibson Dunn & Crutcher's London arm has secured a role advising US private equity house Westbrook Partners on its £500m acquisition of Shell Mex House on the Strand.

Westbrook bought the property from a consortium including Robert and Vincent Tchenguiz, the Reuben brothers, David and Simon, and Jack Dellal.

The consortium was advised by Herbert Smith property partner Chris de Pury, who is set to join Berwin Leighton Paisner early next year.

Gibson Dunn's team was led by real estate partner Alan Samson, assisted by tax partner Nicholas Aleksander and employment partner James Cox. The team was supported by corporate associates Oliver s'Jacob, Sian Owles and Milena Radoycheva.

The building, which has been the subject of a number of aborted sales, houses bluechip tenants, including Shell and the Pearson Group.

Gibson Dunn has acted for Westbrook as its primary UK counsel since 1998, including the acquisition of Dolphin Square for around £200m and a £400m property portfolio from Prudential in 2005.