6,8-Dibromoimidazo[1,2-a]pyrazine

Uses

It is an Intermediate in organic syntheses.

Uses

6,8-Dibromoimidazo[1,2-a]pyrazine is a imidazopyrazine derivative with uterine-relaxing, antibronchospastic, and cardiac-stimulating properties. 6,8-Dibromoimidazo[1,2-a]pyrazine also displays theophylline-like properties.

Synthesis

1. 3,5-dibromopyrazin-2-amine (1018 g, 4.03 mol) was dissolved in water (10 kg) at room temperature. 2. 2-bromo-1,1-dimethoxyethane (1.79 kg, 4.14 mol) was added to the above solution and mixed with stirring. 3. The reaction mixture was heated to reflux and held for 2 hours. 4. After the reaction was complete, water (15.3 kg) and sodium bicarbonate (744 g) were added to the reaction solution and stirring was continued for 15 minutes. 5. The reaction mixture was filtered and the solid product was collected. 6. 6. After drying, 6,8-dibromoimidazo[1,2-A]pyrazine (1106 g, 3.99 mmol, 99% yield) was obtained as a brown solid. 7. The structure of the product was confirmed by 1H-NMR (400 MHz, DMSO-d6): δ 7.90 (s, 1H), 8.23 (s, 1H), 9.02 (s, 1H).

References

[1] Patent: US2012/59162, 2012, A1. Location in patent: Page/Page column 53-54
[2] Patent: WO2005/85252, 2005, A1. Location in patent: Page/Page column 37-38; 40-41
[3] Journal of Medicinal Chemistry, 2015, vol. 58, # 1, p. 512 - 516
[4] Patent: WO2016/209895, 2016, A1. Location in patent: Paragraph 15; 16