1-ethyl-3-[(1-oxo-2-phenylethyl)amino]thiourea

1-ethyl-3-[(1-oxo-2-phenylethyl)amino]thiourea, also known as **EPTU**, is a synthetic compound that acts as a potent and selective inhibitor of **ornithine decarboxylase (ODC)**.

Here's why it's important for research:

**ODC and its role in cell growth and proliferation:**

* ODC is a key enzyme in the biosynthesis of polyamines, which are essential for cell growth, proliferation, and differentiation.
* ODC catalyzes the decarboxylation of ornithine to putrescine, the first step in the polyamine biosynthetic pathway.
* Elevated ODC activity is associated with various cancers and other proliferative diseases.

**EPTU as a research tool:**

* **Inhibiting ODC activity:** EPTU acts as a mechanism-based inhibitor of ODC, meaning it forms a stable covalent complex with the enzyme, effectively shutting down its activity. This makes EPTU a valuable tool for studying the role of ODC in various biological processes.
* **Investigating polyamine metabolism:** EPTU allows researchers to manipulate polyamine levels in cells and organisms, enabling them to study the effects of these changes on cell growth, proliferation, and other biological functions.
* **Developing new anti-cancer drugs:** The potent ODC inhibitory activity of EPTU has led to its investigation as a potential anti-cancer agent. EPTU itself has not progressed to clinical use, but its structure has served as inspiration for the development of other ODC inhibitors.

**EPTU is not a drug currently used in human therapy.** However, it remains a crucial research tool for understanding the role of ODC in cell growth, proliferation, and disease. Its use has contributed to the development of new insights into polyamine metabolism and its potential therapeutic targets.