Hydrochloric Acid → HCID 20434941, compound

Participants

Reaction Steps

Sodium borohydride (0.025 g) was added at room temperature to a stirred solution of 1-(6,7-dimethoxyquinazolin-4-yl)-4-[1-(1,1-dioxo-5-methyl-1,2,6-thiadiazin-2-yl)prop-2-yl]piperidine (0.30 g) (Example 35) in absolute ethanol (5 ml.). After stirring for 16 hours, the mixture was acidified to pH1 with 2M hydrochloric acid and concentrated in vacuo. The residue was treated with aqueous sodium carbonate solution to pH12, extracted with chloroform (3×10 ml.), and the combined extracts were dried (MgSO4) and evaporated to yield an oil which was chromatographed on silica ("Merck 60.9385") eluting with methanol:ethyl acetate, 1:20, to give a solid. Recrystallisation from ethyl acetate-ether afforded 1-(6,7-dimethoxyquinazolin-4-yl)-4-[1-(1,1-dioxo-5-methyltetrahydro-1,2,6-thiadiazin-2-yl)prop-2-yl]piperidine as white microcrystals, m.p. 172°-175°, (0.15 g).

Provenance & Evidence