Synthesis of synthetic small molecule transcription factors (STF)

External control of gene expression by small synthetic molecules represents a challenge in chemistry. Here we discuss the synthetic aspects of small molecule transcription factor mimics including a molecule we call STF1 (1). STF1 stimulates the transcription of a reporter gene controlled by specific DNA elements and behaves just as a naturally occurring transcription factor. However, STF1 had limited cell permeability, even though the hairpin-polyamide-FITC conjugate and the wrenchnolol (2) are cell permeable as separate compounds. Systematic synthetic exploration of STF1 analogs (STFs), by optimizing the physical properties of the molecule, is expected to increase its cell permeability for biological studies.