What molecule am I?
Allicin is a sulfinothionate compound that is formed when fresh garlic (Allium sativum) is cut up. It is responsible for the characteristic odor of garlic.
Allicin was isolated in 1944 by Chester J. Cavallito* and John Hays Bailey at Winthrop Chemical Co.1 (Rensselaer, NY), who also named it, determined its physical properties, and found that it was active against Gram-positive and Gram-negative bacteria. In a subsequent article, Cavallito, Johannes S. Buck, and C. M. Suter determined the molecule’s structure.
The synthesis of allicin and similar compounds was reported in 1950 in US Patent 2,508,745 to Cavallito and La Verne D. Small at Sterling Drug2 (Wilmington, DE). The inventors treated alkyl and aryl disulfides with peroxyphthalic acid3 at low-to-moderate temperatures to obtain good yields of the desired products. The synthetic allium was identical to the natural product.
When garlic cloves are crushed, the constituent alliin4 is converted by the enzyme alliinase5 to allicin. In 2021, Ondřej Kašpar at the University of Chemistry and Technology Prague and coauthors there and at other institutions in the Czech Republic, Canada, and India described the ideal conditions under which purified alliinase can produce allicin in high yields. Their purpose was to provide a method for making allicin in sufficient amounts to develop it as an antibacterial drug, especially to combat multidrug-resistant bacterial strains.
1. Now defunct. Winthrop became notorious in 1940, when it released a contaminated batch of the drug sulfathiazole, leading to hundreds of injuries and deaths. This incident led to the US Food and Drug Administration’s establishment of good manufacturing practices for drugs.
2. Successor to Winthrop Chemical.
3. CAS Reg. No. 1203-40-3.
4. CAS Reg. No. 556-27-4.
5. CAS Reg. No. 9031-77-0.
Allicin hazard information*
| Hazard class** | GHS code and hazard statement | |
|---|---|---|
| Flammable liquids, category 2 | H225—Highly flammable liquid and vapor |  |
| Acute toxicity, oral, category 3 | H301—Toxic if swallowed |  |
| Acute toxicity, dermal, category 3 | H311—Toxic in contact with skin | |
| Skin corrosion/irritation, category 2 | H315—Causes skin irritation |  |
| Serious eye damage/eye irritation, category 2A | H319—Causes serious eye irritation | |
| Acute toxicity, inhalation (dusts/mists), category 3 | H331—Toxic if inhaled | |
| Specific target organ toxicity, single exposure, respiratory tract irritation, category 3 | H335—May cause respiratory irritation | |
| Carcinogenicity, category 1B | H350—May cause cancer |  |
| Specific target organ toxicity, single exposure, category 1 | H370—Causes damage to the central nervous system and the visual organs | |
*Compilation of multiple safety data sheets.
**Globally Harmonized System (GHS) of Classification and Labeling of Chemicals. Explanation of pictograms.
Molecules from the Journals
Nitrogen trifluoride1 (NF3) is a colorless gas that is chemically inert but somewhat toxic. Its synthesis was first reported in 1928 by Otto Ruff*, Joseph Fischer, and Fritz Luft at the Technical University of Breslau (Germany), who made it via the electrolysis of ammonium hydrogen fluoride2 (NH4F2H).
NF3 has applications in etching, especially for computer components and solar cells; but it is also a greenhouse gas. In September, Bo Yao at Fudan University (Shanghai) and collaborators there and at other institutions in China, the United States, and the United Kingdom reported the estimated NF3 emissions in China from 2017 to 2021, based on atmospheric observations from nine testing stations. They found a 48% increase in emissions during the testing period. The increase was comparable to global emissions during the same period.
Iodine3 is both an element and a diatomic molecule. It was discovered in and isolated from seaweed ash in 1811 by French chemist Bernard Courtois. Neutral iodine and its many oxidation states have important uses in medicine, chemical synthesis, and household products.
Radioactive iodine emitted from nuclear power plants and waste treatment facilities poses an environmental hazard. Last month, Feng Luo, Li Wang, and co-workers at the East China University of Technology (Nanchang, China) reported that iodine can be captured from vapor and solution phases with the use of a thorium-based metal–organic framework (MOF). The MOF consisted of a Th4+ ion surrounded by what the authors describe as a naphthalenediimide-related poly(carboxylate) ligand. The thorium itself is a radioactive waste.
1. CAS Reg. No. 7783-54-2.
2. CAS Reg. No. 1341-49-7.
3. CAS Reg. No. 7553-56-2.
Molecules from the Journals
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Allicin fast facts
| CAS Reg. No. | 539-86-6 |
| SciFindern name | 2-Propene-1-sulfinothioic acid, S-2-propen-1-yl ester |
| Empirical formula | C6H10OS2 |
| Molar mass | 162.28 g/mol |
| Appearance | Colorless liquid |
| Melting point | <25 °C |
| Boiling point | ≈37–70 °C (dec.) |
| Water solubility | ≈8 g/L |
Learn more about this molecule from CAS, the most authoritative and comprehensive source for chemical information.
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