(4aS,4bR,5aR,6aS,7R,9aS,9bR,10R)-7-(2-carboxyethyl)-7-hydroxy-4a,6a-dimethyl-2-oxo-2,3,4,4a,5a,6,6a,7,8,9,9a,9b,10,11-tetradecahydrocyclopenta[1,2]phenanthro[4,4a-b]oxirene-10-carboxylic acid, disodium salt