The Collaborative International Dictionary of English v.0.48:

digitalin \dig"i*ta`lin\, n. [Cf. F. digitaline.]
      (a) (Medicine, Pharmacy) Any one of several extracts of
          foxglove (Digitalis), as the "French extract," the
          "German extract," etc., which differ among themselves
          in composition and properties. Both Digitalis lanata
          and Digitalis purpurea have been used to prepare
          such extracts.
      (b) (Chem.) the distinctive chemical substance, a steroid
          glycoside, which is the essential ingredient of the
          extracts of foxglove. It is a white, crystalline
          substance (C36H56O14), and is a 3-substituted
          diglucoside of a steroid. It is a powerful cardiac
          stimulant and is used as a cardiotonic for treatment
          of certain heart conditions, such as congestive heart
          failure. Chemically it is

          (3[beta],5[beta],16[beta])-3-[6-Deoxy-4-O-[beta]-D-glucopyranosyl-3-O-methyl-[beta]-D-galactopyranosyl)oxy]-14,16-dihyroxy-card-20
          (22)-enolide. The related compounds digitoxin and
          digoxin are also extracted from the foxglove. The
          class of steroid glycosides having cardiotonic
          properties are refered to as the cardiac glycosides.
          --MI11

   Syn: digitalinum verum, Diginorgin, Schmiedeberg's digitalin,
        digitalis, digitalis glycoside. [1913 Webster +PJC]

The Collaborative International Dictionary of English v.0.48:

digitoxin \dig`i*tox"in\ (d[i^]j`[i^]*t[o^]k"s[i^]n), n. (Chem.)
   A steroid glycoside, one of the cardiotonic chemical
   substances which is extracted from the foxglove. It is a
   white, crystalline substance (C41H64O13), and is a
   3-substituted triglucoside of a steroid, related structurally
   to digitalin and digoxin. It is used as a cardiotonic for
   treatment of certain heart conditions, such as congestive
   heart failure. Chemically it is

   (3[beta],5[beta])-3-[(O-2,6-Dideoxy-[beta]-D-ribo-hexopyranosyl-(1[rarr]4)-O-2,6-dideoxy-[beta]-D-ribo-hexopyranosyl-(1[rarr]4)-2,
   6-dideoxy-[beta]-D-ribo-hexopyranosyl)oxy]-14-hydroxy-card-20(22)-enolide.
   The related compounds digitalin and digoxin are also
   extracted from the foxglove (Digitalis lanata and
   Digitalis purpurea). The class of steroid glycosides having
   cardiotonic properties are refered to as the cardiac
   glycoside group. --MI11
   [PJC]

The Collaborative International Dictionary of English v.0.48:

digoxin \di*gox"in\, n. (Chem.)
   a steroid glycoside, one of the cardiotonic chemical
   substances which is extracted from the foxglove. It is a
   white, crystalline substance (C41H64O14), and is a
   3-substituted triglucoside of a steroid, related structurally
   to digitalin and digitoxin. It is used as a cardiotonic for
   treatment of certain heart conditions, such as congestive
   heart failure. Chemically it is

   (3[beta],5[beta],12[beta])-3-[(O-2,6-Dideoxy-[beta]-D-ribo-hexopyranosyl-(1->4)-O-2,6-dideoxy-[beta]-D-ribo-hexopyranosyl-(1->4)-2
,  6-dideoxy-[beta]-D-ribo-hexopyranosyl)oxy]-12,14-dihydroxy-card-20(22)-enolide.
   The related compounds digitalin and digoxin are also
   extracted from the foxglove (Digitalis lanata and
   Digitalis purpurea). The class of steroid glycosides having
   cardiotonic properties are refered to as the cardiac
   glycosides. --MI11
   [PJC]