Cardioactive digitoxigenin-aminoesters - from digitoxigenin and protected aminoacid derivs in pyridine

摘要

Cpds. of formula (I) or their strophanthidin-equivs. (where R = H, alkenyl, cycloalkyl, aryl, alkaryl or aralkyl; R1 and R11 = H, 1-4C alkyl or acyl derived from aminoacids or oligopeptides, or R1 + R11 = phthaloyl, or NR1R11 = satd. heterocycle, are cardioactive, have low toxicity, rapid action and good absorption on oral administration. Prepd. from digitoxigenin and aminoacid- or oligopeptide derivs. where the NH2-gp. is protected and the COOH-gp. activated. In an example, 2.55 g. digitoxigenin-3-phthalimidoacetate, m.pt. 259-261 degrees is obtd. from 3 g. (8.04 mol.) digitoxigenin and 3.3 g. (16.12 mol.) phthalylglycine (converted to the chloride with C6H5SO2Cl) in pyridine.