Hydrochloric Acid → 4-(3-Amino-1,2,4-triazin-5-yl)-1-azabicyclo[2.2.1]heptane

4-(α-bromoacetyl) -1 -azabicyclo[2.2.1 ]heptane hydrobromide (EP-0366304, Description 19) (0.5 g, 1.67 mmol) was converted into 2-oxo-2- (1-azabicyclo [2.2.1]hept-4-yl)ethanal hydrobromide as described in Example 3. The crude aldehyde was immediately treated with a suspension of aminoguanidine bicarbonate (0.25 g, 1.84 mmol) in water (10 ml) and the solution was acidified to pH6 with 5M hydrochloric acid. After stirring overnight at room temperature the reaction mixture was saturated with potassium carbonate then extracted into chloroform (4×20 ml). The combined organic extracts were dried over sodium sulphate and concentrated in vacuo. The residue was crystallised from isopropanolpentane to afford the title compound (E4) as a brown solid (0.14 g, 43%) . This was converted into the oxalate salt m.p. 178° C. (dec) (from methanol-ether).

1. extractionthen extracted into chloroform (4×20 ml)
2. dry with materialThe combined organic extracts were dried over sodium sulphate
3. concentrationconcentrated in vacuo
4. customThe residue was crystallised from isopropanolpentane

ORD record

ord-b3b9b695650f4cf9a5d343f089e77cbf

Source dataset

uspto-grants-1994_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05324724