Synthesis of 3-Substituted Benzoxazoline-2-thiones

Masatoshi Yamato, Yasuo Takeuchi, Kuniko Hashigaki, Kyoko Hattori, Eiko Muroga, Takashi Hirota

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Several methods for the preparations of 3-substituted benzoxazoline-2-thiones (1) were examined. Method B via the thiation of 3-substituted benzoxazolin-2-one (5) with phosphorus pentasulfide was found to be applicable to the preparation of most analogs of 1, with a few exceptions. Method C via the cyclization of 2-(alkylamino)phenol (7) with potassium O-methyldithiocarbonate was suitable for the preparation of analogs with a group sensitive to high temperature or with an aryl- (including aromatic hetero-cyclic ring) methyl group. In addition, the reaction of benzoxazoline-2-thione (2) with acetals such as 1-ethoxy-isochroman, 2-ethoxytetrahydrofuran, and 2-ethoxytetrahydropyran, or with Michael acceptors such as 2,3-dihydrofuran and 2H-3,4-dihydropyran, gave 3-substituted benzoxazoline-2-thione (1d—f).

Original languageEnglish
Pages (from-to)1733-1737
Number of pages5
JournalChemical and Pharmaceutical Bulletin
Volume31
Issue number5
DOIs
Publication statusPublished - 1983

Fingerprint

Thiones
Acetals
Cyclization
Phenol
Potassium
Temperature

Keywords

  • 2-(alkylamino) phenol
  • 2-(alkylthio)benzoxazole
  • 3-substituted benzoxazolin-2-one
  • 3-substituted benzoxazoline-2-thione
  • acetal
  • Michael acceptor
  • thiation
  • UV spectra

ASJC Scopus subject areas

  • Chemistry(all)
  • Drug Discovery

Cite this

Yamato, M., Takeuchi, Y., Hashigaki, K., Hattori, K., Muroga, E., & Hirota, T. (1983). Synthesis of 3-Substituted Benzoxazoline-2-thiones. Chemical and Pharmaceutical Bulletin, 31(5), 1733-1737. https://doi.org/10.1248/cpb.31.1733

Synthesis of 3-Substituted Benzoxazoline-2-thiones. / Yamato, Masatoshi; Takeuchi, Yasuo; Hashigaki, Kuniko; Hattori, Kyoko; Muroga, Eiko; Hirota, Takashi.

In: Chemical and Pharmaceutical Bulletin, Vol. 31, No. 5, 1983, p. 1733-1737.

Research output: Contribution to journalArticle

Yamato, M, Takeuchi, Y, Hashigaki, K, Hattori, K, Muroga, E & Hirota, T 1983, 'Synthesis of 3-Substituted Benzoxazoline-2-thiones', Chemical and Pharmaceutical Bulletin, vol. 31, no. 5, pp. 1733-1737. https://doi.org/10.1248/cpb.31.1733
Yamato, Masatoshi ; Takeuchi, Yasuo ; Hashigaki, Kuniko ; Hattori, Kyoko ; Muroga, Eiko ; Hirota, Takashi. / Synthesis of 3-Substituted Benzoxazoline-2-thiones. In: Chemical and Pharmaceutical Bulletin. 1983 ; Vol. 31, No. 5. pp. 1733-1737.
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