The phrase "is less interested than" is grammatically correct and can be used in written English.
It is typically used to compare the level of interest between two or more people or things. Example: "Samantha is less interested in sports than her brother."
Britain is less interested than usual.
Mr. Giraud is less interested than Mr. Richard in creating dishes; he perfects old ones.
The ad shows that the president is less interested than anyone in advertising the moderate credentials of his rival.
Her lack of chemistry with Mr Patriota is well-known; but she likes Mr Figueiredo, who was in charge of last year's Rio+20 environmental summit.The change will have little effect on Brazil's foreign policy, in which Ms Rousseff is less interested than her predecessor, Luiz Inácio Lula da Silva.
In the same year the English Defence League (EDL) was born, introducing a new form of far-right politics that is less interested than its predecessors in elections, and more focused on rallying support through street-based confrontation and networks that transcend national borders.
They are right that in any first meeting or conversation, the VC is less interested than the entrepreneur.
Bob was less interested than Mike is in this discussion.
Indeed, the music press was less interested than the police.
Before the conventions this year, there was an overall perception that the television audience would be less interested than in 1996.
But Disney also said that its research indicated that mothers were less interested than they used to be in programs that promote academic goals.
"It is an open secret that for whatever reasons — cultural, biological, or a mix of both — women generally tend to be less interested than men in competitive athletics," Cathy Young, a libertarian commentator, wrote in a recent blog entry.
