D&D London has bought the Madison Bar and Restaurant, at London's One New Change, for £4.5m.
The tapas restaurant on the sixth floor of the City development, which will be D&D's ninth venue in the capital, was originally founded by disgraced American businessman Frank Dowling.
The new 130-cover restaurant and bar will serve an all-day brasserie menu, with tapas on offer in the bar along with wine, champagne and cocktails.
D&D London chairman Des Gunewardena said: "This is an absolute stunner of a site with amazing views over the City. We will in due course be making some changes to the food concept, to the service and also to the physical fabric of the venue. But this is a very successful business and so we will maintain the overall concept of the restaurant, bar and outdoor terraces."
The site was acquired from the administrators of Greenwich Inc. and Madison, who were appointed to handle Dowling's firm when it fell into administration in November.
A month later he was held as part of a tax fraud investigation by HM Revenue & Customs amid allegations of £6m of undeclared VAT and PAYE. His companies were also reported to be up to a further £9m in debt.
The proceeds of the sale will be used to meet creditors' claims.
Dowling described the site at One New Change as "arguably the most profitable bar/restaurant per square foot in London".
"I am sure it will continue to thrive in the expert hands of D&D. We have cooperated fully with the insolvency process and I am now looking forward to moving ahead with a number of exciting business opportunities, not only in London but throughout the UK," he added.