title: [Steroidal cardiotonics. I. Introduction of substituents into the butenolide ring of heart glycosides].
mesh_terms: D002301:Cardiac Glycosides; D055598:Chemical Phenomena; D002621:Chemistry; D003500:Cyclization; D006900:Hydroxylation; D013057:Spectrum Analysis; D013329:Structure-Activity Relationship
chemical_list: D002301:Cardiac Glycosides
vernacular_title: Steroidische Cardiotonica. I. Einführung von substituenten in den Butenolid-Ring von Herzglykosiden.