Work to turn the dilapidated and vacant Jefferson Arms into offices, apartments, restaurants and a hotel could begin as early as January, the prospective developer said Thursday.

Mike Sarimsakci, whose Dallas-based Alterra International has the 13-story downtown St. Louis building under contract, said he plans to complete the purchase in December. Clearing the Jefferson Arms of debris and beginning the environmental cleanup would then get underway, he said.

Renovation will begin with construction of shops and restaurants on the first floor and in the basement of the Jefferson Arms, at 415 North Tucker Boulevard, Sarimsakci said in an interview in St. Louis. Opening the retail outlets will occur before completion of market-rate apartments in the original section of the historic building that debuted as the Hotel Jefferson in time for the 1904 World’s Fair. Apartments also would occupy the top two floors of the hotel’s 1920s addition on Locust Street.

A hotel of about 240 rooms will fill the rest of the addition, said Sarimsakci, adding that the operator might be the Trump, Marriott or Divan Group hotel chain. The entire project could be done by January 2020.