4072 Ouabain Ouabain is only found in individuals that have used or taken this drug. It is a cardioactive glycoside consisting of rhamnose and ouabagenin, obtained from the seeds of Strophanthus gratus and other plants of the Apocynaceae; used like digitalis. It is commonly used in cell biological studies as an inhibitor of the NA(+)-K(+)-exchanging ATPase. Ouabain inhibits the Na-K-ATPase membrane pump, resulting in an increase in intracellular sodium and calcium concentrations. Increased intracellular concentrations of calcium may promote activation of contractile proteins (e.g., actin, myosin). Ouabain also acts on the electrical activity of the heart, increasing the slope of phase 4 depolarization, shortening the action potential duration, and decreasing the maximal diastolic potential. 630-60-4 439501 C29H44O12 White powder. 200°C 1.03E+004 mg/L Ouabain inhibits the Na-K-ATPase membrane pump, resulting in an increase in intracellular sodium and calcium concentrations. Increased intracellular concentrations of calcium may promote activation of contractile proteins (e.g., actin, myosin). Ouabain also acts on the electrical activity of the heart, increasing the slope of phase 4 depolarization, shortening the action potential duration, and decreasing the maximal diastolic potential. No indication of carcinogenicity to humans (not listed by IARC). For the treatment of atrial fibrillation and flutter and heart failure 2014-08-29T04:49:16Z 2026-05-14T16:57:45Z Ouabain C01443 472805 DB01092 OBN true [H][C@@]12CC[C@]3(O)C[C@H](C[C@@H](O)[C@]3(CO)[C@@]1([H])[C@H](O)C[C@]1(C)[C@H](CC[C@]21O)C1=CC(=O)OC1)O[C@@H]1O[C@@H](C)[C@H](O)[C@@H](O)[C@H]1O C29H44O12 InChI=1S/C29H44O12/c1-13-22(34)23(35)24(36)25(40-13)41-15-8-19(32)28(12-30)21-17(3-5-27(28,37)9-15)29(38)6-4-16(14-7-20(33)39-11-14)26(29,2)10-18(21)31/h7,13,15-19,21-25,30-32,34-38H,3-6,8-12H2,1-2H3/t13-,15-,16+,17+,18+,19+,21+,22-,23+,24+,25-,26+,27-,28+,29-/m0/s1 LPMXVESGRSUGHW-HBYQJFLCSA-N 584.6525 584.283276872 Exogenous Solid -2 HMDB15224 CHEMBL222863 388599 CHEM002978 DTXSID0043765 NS00003260 4-[(1R,3aS,3bR,5aS,7S,9R,9aR,9bS,10R,11aR)-3a,5a,9,10-tetrahydroxy-9a-(hydroxymethyl)-11a-methyl-7-{[(2R,3R,4R,5R,6S)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxy}-hexadecahydro-1H-cyclopenta[a]phenanthren-1-yl]-2,5-dihydrofuran-2-one 206.59999999999997 140.83379999999994 59.92556829434825 4 11 8 7.181446894362235 -2.8503841755458543 0 6 -1.03 -2.10 4.61e+00 g/l