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Product Code B3421-500mg
Price $57 ex. VAT

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A fluorinated benzoxazole building block

Serves as a synthesis intermediate for APIs


5-Fluorobenzoxazole-2-thiol (CAS number 13451-78-0), also known as 5-fluoro-2-mercaptobenzoxazole, is a benzoxazole derivative featuring thiol and fluoride functional groups. Benzoxazole plays an important role in drug discovery, while the thiol group enables 5-fluorobenzoxazole-2-thiol to achieve desirable bioactivities via nucleophilic substitution. 5-Fluorobenzoxazole-2-thiol is modified with pyrrolidinamide for prodrugs against Mycobacterium tuberculosis, exhibiting a potency of 1.6 μM. Additionally, 5-Fluorobenzoxazole-2-thiol couples with phenylhydrazide derivatives, showing potential as antiglioma agents for anticancer drugs.

The thiol group in 5-fluorobenzoxazole-2-thiol can be converted to an amine through facile microwave- or visible light-assisted amination reactions.

Multiple functional groups

Multiple functional groups

For facile synthesis

Fluorinated benzoxazole building block

Fluorinated benzoxazole building block

For drug discovery, medicinal chemistry, and organic synthesis

competitively priced 13451-78-0

Low Cost

Competitively priced, high quality product

High purity 13451-78-0

High purity

>97% High purity

General Information

CAS Number 13451-78-0
Chemical Formula C7H4FNOS
Full Name 5-Fluoro-1,3-benzoxazole-2(3H)-thione
Molecular Weight 169.18 g/mol
Synonyms 2-Mercapto-5-fluorobenzoxazole, 5-Fluoro-2-mercaptobenzoxazole, 5-Fluoro-2(3H)-benzoxazolethiene
Classification / Family Fluorinated building blocks, Benzoxazole building blocks, Heterocyclic building blocks, APIs

Chemical Structure

5-Fluorobenzoxazole-2-thiol chemical structure, CAS 13451-78-0
5-Fluorobenzoxazole-2-thiol chemical structure, CAS 13451-78-0

Product Details

Purity 97%
Melting Point Tm = 238 °C – 240 °C
Appearance Off-white powder

MSDS Documentation

5-Fluorobenzoxazole-2-thiol5-Fluorobenzoxazole-2-thiol MSDS Sheet

Literature and Reviews

  1. Microwave-enhanced on-water amination of 2-mercaptobenzoxazoles to prepare 2-aminobenzoxazoles, T. Tankam et al., J. Org. Chem., 83 (19), 11936–11943 (2018); DOI: 10.1021/acs.joc.8b01824.
  2. Organocatalytic visible light enabled SNAr of heterocyclic thiols: a metal-free approach to 2-aminobenzoxazoles and 4-aminoquinazolines, E. Rattanagkool et al., J. Org. Chem., 82 (24), 13256–13262 (2017); DOI: 10.1021/acs.joc.7b02357.
  3. Substitution-modulated anticancer activity of half-sandwich ruthenium(II) complexes with heterocyclic ancillary ligands, R. Mitra et al., Eur. J. Inorg. Chem., 2014 (22), 3536–3546 (2014); DOI: 10.1002/ejic.201402205.
  4. MymA bioactivated thioalkylbenzoxazole prodrug family active against Mycobacterium tuberculosis, A. Moure et al., J. Med. Chem., 63, 4732–4748 (2020); DOI: 10.1021/acs.jmedchem.0c00003.
  5. Synthesis and evaluation of new benzoxazole derivatives as potential antiglioma agents, M. Altintop et al., Marmara Pharm. J., 22 (4), 547–558 (2018); DOI: 10.12991/jrp.2018.97.

To the best of our knowledge the information provided here is accurate. The values provided are typical at the time of manufacture and may vary over time and from batch to batch. Products may have minor cosmetic differences (e.g. to the branding) compared to the photos on our website. All products are for laboratory and research and development use only.

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