反应详情

A solution of 7-amino-2-(2-furyl)-5-methylsulphonyl[1,2,4]triazolo[1,5-a][1,3,5]triazine (1.6 g) in ethanol (40 ml) containing DBU (1.0 ml) was heated under reflux until no starting material remained by TLC analysis. The solvent was removed by evaporation and the residue purified by chromatography on silica using 5-10% v/v ethyl acetate in dichloromethane as eluant, followed by crystallisation from ethanol to give 7-amino-5-ethoxy-2-(2-furyl)[1,2,4]triazolo[1,5-a][1,3,5]triazine as hygroscopic crystals, m.p. 211°-213° C.; microanalysis, found: C, 48.7; H, 4.5; N, 31.4; H2O, 1.2%; C10H10N6O2. 0.33C2H5OH. 0.165H2O requires: C, 48.4; H, 4.7; N, 31.8; H2O, 1.1%; NMR: 1.05(t, 1H, CH3CH2OH), 1.35(t, 3H, CH3CH2), 3.4(q, CH3CH2OH), 4.3(q, 2H, CH3CH2O--), 6.7(dd, 1H, furyl-4H), 7.1(d, 1H, furyl-3H), 7.9(d, 1H, furyl-5H), 8.5-9.0(d, 2H, NH2); m/e 246 (M+).

1. temperaturewas heated
2. temperatureunder reflux until no starting material
3. customThe solvent was removed by evaporation
4. customthe residue purified by chromatography on silica using 5-10% v/v ethyl acetate in dichloromethane as eluant
5. customfollowed by crystallisation from ethanol