Veteran restaurant investor Luke Johnson is reported to be among the bidders interested in Gaucho restaurants.
American asset management fund Carlyle Strategic Partners and M Restaurants boss Martin Williams are also understood to be interested in the chain, which fell into administration last month.
It is understood that a deal to sell the Gaucho restaurants will be agreed in the coming weeks.
Administrators Deloitte closed 22 Cau branches with immediate effect, but 16 Gaucho restaurants continue to trade while a buyer is sought.
Deloitte said the Cau brand was "significantly loss-making" having suffered negative like-for-like sales for three years. Its collapse resulted in 540 redundancies.
Joint administrator Matt Smith said that in comparison the Gaucho brand "continues to trade well in its market segment, is profitable and has a strong underlying brand and guest loyalty".