The financing includes about $34 million in new debt and replaces the balance of a roughly $55 million loan Capital One provided on the property in 2012.
Representatives for Meringoff and Signature were not immediately available for comment.
The 12-story Midtown South building at the corner of 28th Street is fully occupied, with tenants such as WeWork.
Correction: A previous version of this story incorrectly listed the building owner as Himmel + Meringoff Properties. The owner is Meringoff Properties.