Regulation of gene expression by transcription factors touches many aspects of eukaryotic biology, and its systematic, external control by organic molecules represents a challenge in chemistry. Here we report the design of a completely organic, nonpeptidic compound that mimics a transcription factor. The design takes advantage of the specific DNA-binding affinity of a hairpin polyamide molecule and the ability of wrenchnolol to bind to the Sur-2 subunit of human mediator complex. The hybrid compound of these two molecules activates transcription of a reporter gene in vitro in a promoter-dependent manner through simultaneous contacts with DNA and Sur-2. Our results indicate that it is possible to generate a transcription factor out of nonpeptidic components.