What molecule am I?
Glabrene is a natural isoflavonoid that consists of two benzopyran ring systems with methyl and hydroxyl substituents. In 1976, Takeshi Kinoshita, Tamotsu Saitoh, and Shoji Shibata at the University of Tokyo reported its isolation from the roots of the licorice plant (Glycyrrhiza glabra).
Licorice root, widely used in traditional Chinese medicine, has several bioactive components, including glabrene and the closely related isoflavonoid glabridin1. Studies in the early 2000s included the 2001 finding by Jacob Vaya and collaborators at the Migal-Galilee Technological Center (Kiryat Shmona, Israel) and Tel Aviv University that glabrene, more so than glabridin, exhibited a high degree of estrogen receptor agonism. The authors reported “The stimulatory effects of glabrene in vivo were tissue specific and similar to those of estradiol2.”
Two years later, Snait Tamir and colleagues at Migal-Galilee and Tel-Hai Academic College (Upper Galilee, Israel) reported that glabrene and another licorice root component, isoliquiritigenin3, are inhibitors of the enzyme tyrosinase, a key factor in melanin biosynthesis. This result was significant because excessive melanin pigmentation can cause skin disorders such as melasama, age spots, and actinic damage.
Two 2024 reports describe negative and positive effects of glabrene. Qiang Zhang and co-workers at Northwest A&F University (Yangling, China) found that glabrene impurities in glabridin, now a commercial drug used for skin lightening to combat hyperpigmentation disorders, can cause toxic effects in patients’ skin. The researchers used a standard zebrafish toxicity test to determine that glabrene has a significant lethal effect at low doses. They assert that their results show that enhanced quality control methods should be developed for purifying licorice-derived products.
On the positive side, Guoduo Zhang, Shumei Wang, and colleagues at the College and Hospital of Traditional Chinese Medicine (Chongqing) reported that glabrene could be useful for treating non–small cell lung cancer (NSCLC). In experiments on laboratory animals, they found that glabrene suppressed tumor growth by reversing the pathological morphology of tumor tissue and attenuating cancer cell proliferation, migration, and invasion. The key mechanism was the suppression of fibroblast growth factor receptor 3, a protein in NSCLC cells.
For further reading, see the ScienceDirect topics page on glabridin, which includes information on glabrene.
1. CAS Reg. No. 59870-68-7.
2. CAS Reg. No. 50-28-2.
3. CAS Reg. No. 961-29-5.
Glabrene hazard information
| Hazard class* | GHS code and hazard statement | |
|---|---|---|
| Skin corrosion/irritation, category 2 | H315—Causes skin irritation |  |
| Serious eye damage/eye irritation, category 2A | H319—Causes serious eye irritation | |
| Specific target organ toxicity, single exposure, respiratory tract irritation, category 3 | H335—May cause respiratory irritation | |
*Globally Harmonized System (GHS) of Classification and Labeling of Chemicals. Explanation of pictograms.
| Semaglutide | Tirzepatide | |
CAS Reg. No. | 910463-68-2 | 2023788-19-2 |
Developing company | Novo Nordisk (Bagsværd, Denmark) | Eli Lilly (Indianapolis) |
Trade names (diabetes) | Ozempic, Rybelsus | Mounjaro |
Trade names (weight loss) | Wegovy | Zepbound |
FDA approval year (diabetes) | 2017 | 2022 |
FDA approval year (weight loss) | 2023 | 2023 |
Number of amino acids | 31 | 39 |
Empirical formula | C187H291N45O59 | C225H348N48O68 |
Last month, Louis J. Aronne at Weill Cornell Medicine (New York) and 10 collaborators at six institutions in the United States, Ireland, and the United Kingdom reported a comparison of semaglutide and tirzepatide for treating obesity. In a 72-week randomized study of 751 nondiabetic obese patients, the least-squares mean percent weight change was −20.2% with tirzepatide and −13.7% with semaglutide. The waist circumference results were −18.4 cm and −13.0 cm, respectively. Adverse side effects were similarly mild to moderate in both study groups. The authors concluded that tirzepatide is the superior treatment for this patient category.
1. CAS Reg. No. 123475-27-4 (human GLP-1).
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Glabrene fast facts
| CAS Reg. No. | 60008-03-9 |
| SciFinder name | [3,8′-Bi-2H-1-benzopyran]-5′,7-diol, 2′,2′-dimethyl- |
| Empirical formula | C20H18O4 |
| Molar mass | 322.36 g/mol |
| Appearance | White to beige powder |
| Melting point | 200–203 ºC |
| Water solubility | Slight |
Learn more about this molecule from CAS, the most authoritative and comprehensive source for chemical information.
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