Oxazolo[4,5-b]pyridin-2(3H)thione

Chemical Properties

Beige crystalline powder

Synthesis

Step 1: Synthesis of oxazolo[4,5-b]pyridine-2(3H)thione 2-Amino-3-hydroxypyridine (5.0 g, 45.45 mmol) and potassium ethylxanthate (8.0 g, 49.99 mmol) were dissolved in pyridine (50 mL), and the reaction was stirred at 110 °C overnight. Upon completion of the reaction, the mixture was cooled to 0 °C, ice water was added and acidified with concentrated hydrochloric acid. The precipitated solid was collected by filtration and dried under vacuum to afford the target product oxazolo[4,5-b]pyridine-2(3H)thione (6.0 g, 86.95% yield). Product characterization data: 1H NMR (DMSO-d6, 300 MHz): δ 8.24-8.22 (d, 1H), 7.90-7.87 (d, 1H), 7.30-7.26 (m, 1H). LCMS: m/z 153.0 [M + H]+.

References

[1] Patent: WO2015/104688, 2015, A1. Location in patent: Page/Page column 36
[2] Patent: US2016/340366, 2016, A1. Location in patent: Paragraph 0205; 0206
[3] Monatshefte fur Chemie, 2011, vol. 142, # 9, p. 895 - 899
[4] Journal of Organic Chemistry, 1995, vol. 60, # 17, p. 5721 - 5725
[5] European Journal of Medicinal Chemistry, 2005, vol. 40, # 1, p. 15 - 23