Hydrafinil / Fluorenol

Analysis results are found under "attachments" below.

Trade name: 
Synonyms: Fluorenol, 9-fluorenol, 9-Hydroxyfluorene
Formula: C13H10O
Molar mass: 182.22 g/mol

Interactive Image

Precaution and Disclaimer:
This Material is Sold For Research Use Only. Terms and Conditions Apply. 
Not for Human Consumption, nor Medical, Veterinary, or Household Uses.

Tax included

Estimated delivery to United States between Thu, Feb 3 and Fri, Feb 4* via REK (Registered Int'l Mail) if you order within if you order NOW Details

We are basing the estimated delivery times on expected handling time, order cut off times, and receipt of cleared payment. 
Delivery times may vary, especially during peak periods.



What is Hydrafinil?

Hydrafinil, also known as fluorenol, has been firstly reported in the scientific literature back in 1939 after being studied among several potential insecticides(1). However, it was only in 2012 that Dunn and al. discovered its psychopharmacological properties while searching for a new modafinil successor (on the behalf of Cephalon Ltd.) derived from a fluorenyl analog(2).

They highlighted that despite being structurally distant from modafinil, hydrafinil exhibits a more pronounced eugeroic effect in animal models(2). Nonetheless, this substance has been poorly studied since its discovery, and only limited information exists about its mechanism of action, as well as its toxicity and pharmacokinetic profile that have not yet been established. Hydrafinil is consequently not approved for human consumption in any country.

Pharmaceutical properties

Hydrafinil is considered a eugeroic compound, i.e. a family of wakefulness-promoting agents of which modafinil and armodafinil belongs too. Nevertheless, by having a chemical structure vastly distinct from conventional eugeroics, hydrafinil may have a quite different pharmaceutical spectrum, making it potentially unsafe for human consumption.


- Eugeroic properties

Eugeroics related to modafinil usually act as atypical dopamine reuptake inhibitors by binding to dopamine active transporters(3,4), whereas some others act as norepinephrine-dopamine reuptake inhibitors(5) (Solriamfetol) or even in a more exotic way as histamine-3-receptor antagonists/inverse agonists(6) (Pitolisant). Regarding hydrafinil, its mechanism of action remains widely unknown and for now, scientific literature unveiled that: 

  • Hydrafinil exhibits a eugeroic effect 39% stronger than modafinil in mice over a 4 hour period, while paradoxically, its DAT binding affinity appeared to be 59% weaker(2).
    - This observation leads to the hypothesis that hydrafinil may have an addictive potential in mice weaker than modafinil, whereas it also suggests that its eugeroic effect includes other neuronal pathways.
  • Although there are still no experimental studies to verify it, hydrafinil is thought to be an antagonist of the central serotonin receptor 5-HT6.
    - Many studies have shown that the blocking of 5-HT6 receptor in rats can improve cognitive function by increasing glutamatergic and cholinergic neurotransmission in various brain areas, whereas enhancing GABAergic signaling and both dopamine and norepinephrine release in the frontal cortex(7-9).
  • Contrary to modafinil that inhibits cytochrome P450 2C19 activity through binding it(10), one study has shown that hydrafinil displays no affinity toward it when assessed at 10µM in vitro(11).
    - It is estimated that cytochrome P450 2C19 acts on at least 10% of the current drug(12), thus suggesting that hydrafinil is less likely to influence their metabolism than modafinil in vitro.

- Toxicological profile 

Hydrafinil’s toxicological profile is still unknown, but because it belongs to the polycyclic aromatic hydrocarbons (PAH) relative to fluorene, it raises some concerns about its potential toxicity.

  • Fluorene has effectively been shown to cause weak toxicity and a mutagenic effect in animals, while its carcinogenicity hasn’t been investigated enough yet(13).


1. Claiborn, H. W. & Smith, L. E. This application is made under the act of March 3, 1883, as amended by the act of April. 2.
2. Dunn, D. et al. Wake promoting agents: Search for next generation modafinil, lessons learned: Part III. Bioorganic & Medicinal Chemistry Letters 22, 3751–3753 (2012).

3. Urban, A. E. & Cubała, W. J. The role of eugeroics in the treatment of affective disorders. Psychiatr Pol 54, 21–33 (2020).
4. Mereu, M., Bonci, A., Newman, A. H. & Tanda, G. The neurobiology of modafinil as an enhancer of cognitive performance and a potential treatment for substance use disorders. Psychopharmacology (Berl) 229, 415–434 (2013).
5. Reith, M. E. A. et al. Behavioral, biological, and chemical perspectives on atypical agents targeting the dopamine transporter. Drug Alcohol Depend 0, 1–19 (2015).
6. Quisenberry, A. J. & Baker, L. E. Dopaminergic mediation of the discriminative stimulus functions of modafinil in rats. Psychopharmacology 232, 4411–4419 (2015).
7. Strollo, P. J. et al. Solriamfetol for the Treatment of Excessive Sleepiness in OSA: A Placebo-Controlled Randomized Withdrawal Study. Chest 155, 364–374 (2019).
8. Dauvilliers, Y. et al. Long-term use of pitolisant to treat patients with narcolepsy: Harmony III Study. Sleep 42, (2019).
9. Dawson, L. A., Nguyen, H. Q. & Li, P. The 5-HT 6 Receptor Antagonist SB-271046 Selectively Enhances Excitatory Neurotransmission in the Rat Frontal Cortex and Hippocampus. Neuropsychopharmacology 25, 662–668 (2001).
10. Nikiforuk, A. The procognitive effects of 5-HT6 receptor ligands in animal models of schizophrenia. Reviews in the Neurosciences 25, 367–382 (2014).
11. Upton, N., Chuang, T. T., Hunter, A. J. & Virley, D. J. 5-HT6 receptor antagonists as novel cognitive enhancing agents for Alzheimer’s disease. Neurotherapeutics 5, 458–469 (2008).
12. Human Metabolome Database: Showing metabocard for 3-Hydroxyfluorene (HMDB0059802). https://hmdb.ca/metabolites/HMDB0059802.

All chemical compounds have risks. 
Please read the available research and understand the associated risks before handling. 
If you are uncertain of the appropriate handling methods, please consult a qualified professional. 

Product Details

Data sheet

Product form
HDPE bottle

Specific References

Customers who bought this product also bought:
16 other products in the same category: