June 27, 2022
Take me if you’re depressed, but don’t wash me down the drain.
What molecule am I?
Image of Sertraline 3D Image of Sertraline

Sertraline, best known by the brand name Zoloft (Pfizer, New York City), is a venerable antidepressant that was approved by the US Food and Drug Administration in 1991. Its mode of action, common among antidepressants, is as a selective serotonin reuptake inhibitor. The active ingredient in most of its formulations is its hydrochloride1.

Sertraline continues to be a frequently prescribed antidepressant (≈40 million prescriptions in 2019). But its success has come with an environmental cost: This year, a review by South African scientists Lawrence Mzukisi Madikizela* and Somandla Ncubeb cited dozens of drugs, including sertraline, that have been detected in marine organisms and seafood. This finding is a major concern for ocean life because of the aquatic toxicity statements shown in the hazard information table.

1. CAS Reg. No. 79559-97-0.

Sertraline hazard information*

Hazard class** GHS code and hazard statement
Acute toxicity, oral, category 4 H302—May be harmful if swallowed Chemical Safety Warning
Short-term (acute) aquatic hazard, category 1 H400—Very toxic to aquatic life Chemical Safety Warning
Long-term (chronic) aquatic hazard, category 1 H410—Very toxic to aquatic life with long-lasting effects Chemical Safety Warning

*Information from safety data sheets for sertraline and sertraline hydrochloride.
**Globally Harmonized System (GHS) of Classification and Labeling of Chemicals. Explanation of pictograms.

Molecules from the journals

Zinc selenide1 (ZnSe), a salt known since 1921, is seldom found in nature; but it can be made by combining zinc and selenium salts or by heating the elements in a vacuum. It has long been used as a phosphor and semiconductor. This past May, K. David Wegner at the Federal Institute for Materials Research and Testing (Berlin) and co-workers reported that ZnSe “magic-sized” clusters2 are conveniently made by heating zinc stearate, selenourea, and the ligand 1-dodecanethiol in oleylamine solvent. They controlled the cluster sizes by varying the ligand concentration and the reaction temperature.

Guanitoxin3 is a cyanotoxin isolated from cyanobacteria of the genus Anabaena; it causes mammals to salivate excessively by inhibiting the enzyme acetylcholinesterase. Despite its toxicity, guanitoxin is not environmentally monitored because it is incompatible with conventional analytical methods. In May, Shaun M. K. McKinnie, Marli F. Fiore, Bradley S. Moore, and colleagues in several institutions in the United States, Brazil, and Denmark described how guanitoxin can be detected in freshwater bodies by using a gene-sequencing technique.

1. CAS Reg. No. 1315-09-9.
2. Magic-sized clusters of semiconductors are defined as specific molecular-scale arrangements of atoms that exhibit enhanced stability.
3. CAS Reg. No. 103170-78-1.

Molecules from the journals

MOTW briefly describes noteworthy molecules that appeared in recent ACS journal articles. See this week's
edition below

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Sertraline fast facts

CAS Reg. No. 79617-96-2
4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-N-methyl-, (1S,4S)-
Empirical formula C17H17Cl2N
Molar mass 306.23 g/mol
Appearance White crystals or powder
Boiling point 244–246 °C
Water solubility 3.8 g/L

MOTW update

Perovskite was the Molecule of the Week for March 1, 2021. The mineral perovskite is calcium titanate (CaTiO3), but many inorganic compounds with the structure ABX3 are also called perovskites. These substances have several uses, including photovoltaics in solar cells. This month, Lijun Zhang at Jilin University (Changchun, China), Hairen Tan at Nanking University (China), and their colleagues announced a record for the certified energy conversion efficiency of perovskites in flexible thin-film photovoltaics: 24.4%, compared with the previous record of 19.9%.

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