Macdonald hotels is to sell 27 properties to a private equity investor in a deal that will wipe out its £190m debt.
It said that the deal, which includes the Rusacks Hotel, overlooking the 18th green at St Andrews, the Randolph Hotel in Oxford (pictured) and the Bath Spa, would be completed by the end of August.
Donald Macdonald, the group's founder and executive chairman, said: "It's been 30 years since I started the business along with my fellow board members Gerry Smith and Gordon Fraser, and it's been a privilege to have shared such an incredible journey with both of them and with so many other fantastic colleagues."
On Monday Paul Tamburrini's Bistro Deluxe restaurant at the Macdonald Holyrood hotel in Edinburgh, which is among those being sold, closed its doors after the group announced it would be replaced by a new Surf & Turf concept.
Some 11 hotel will be retained, including the Aviemore Highland Resort and four Monument Leisure hotels, as well as a further nine Macdonald Resorts located in the UK and Spain.
Gordon Fraser, deputy chairman and group managing director said: "We are very pleased to have entered a ten-week exclusivity period with a major, heavyweight investor to allow final due diligence and legal work to be completed with the transaction to conclude by the end of August.
"The preferred bidder fits superbly with our ongoing aspirations for the hotels and they will bring significant investment and expansion of the portfolio."
In January it was announced that the group was making around 50 staff redundant due to "unsustainably high costs".
It said difficulties experienced by the businesses as a result of an "above inflation" rise in business rates, alongside the rising costs of minimum wage rates, energy bills, the apprenticeship levy and pension contributions, were highlighted in a letter to staff.
In the most recent accounts for Macdonald Hotels lodged at Companies House, pre-tax profit plunged by 91% from £62.3m to £5.6m, while turnover dropped by £8m to £154.2m for the year to 30 March 2017.
The decline in sales was explained by the loss of trade from three hotels: Swan's Nest in Stratford-upon-Avon, Warwickshire; Old England in Windermere, Cumbria; and the Marine hotel in North Berwick, East Lothian, which had been sold the previous year.
In 1996 Macdonald Hotels & Resorts, which had grown to 100 hotels and resorts with an annual turnover of £240m, was floated on the stock market - a move that Macdonald later admitted was a mistake. "It cost us plenty - in terms of the product - to take the business to market," he told The Caterer in 2007.
The company was brought back into private hands in 2003 through a £620m management-led buyout in a joint venture with the Bank of Scotland which, at the time, was one of the biggest public-to-private deals ever seen in Scotland.
In 2007, the company sold 24 of its UK hotels to Moorfield Real Estate Fund for more than £400m, a move that helped the business to further establish a solid footing in the four- and five-star markets.