Bufagin

Abstract: 1.From the secretion of the parotoid glands of the tropical toad, Bufo agua, we have isolated two distinct, physiologically active crystalline principles. 2. It has been shown by chemical reactions and by analyses, by polarimetric observations, and by qualitative and quantitative physiological experiments that one of these substances is identical with dihydroxy-methyl-amino-ethylol-benzene (epinephrin, adrenalin, suprarenin). 3. It is calculated that the crude venom contains nearly seven per cent (6.72 per cent) of this amino alcohol. 4. By means of chemical reactions and analyses it has been shown that the venom also contains a crystalline principle which we have named bufagin. 5. Bufagin is dextrorotatory (+11°), "neutral" in character, slightly soluble in water and readily soluble in a number of organic solvents. Its melting point is 217-218° C. Its elementary composition and molecular weight are represented by the formula C18H24O4. Its behavior toward bromine shows that it does not contain an unsaturated carbon linkage of cholesterin. 6. The marked action of bufagin on the heart, cardio-inhibitory centre and musculature of the blood-vessels compel us to class this drug with the most efficient members of the digitalis series. Its action on the heart muscle is especially noteworthy. It increases its tonicity, the strength of its contractions and the ventricular volume output. Small doses of the drug cause a marked diuresis. 7. Bufagin does not appear to have a cumulative action and it may be administered hypodermically. 8. The toad, Bufo agua is not at all immune to dihydroxy-methyl-amino-ethylol-benzene, but is relatively immune to bufagin. 9. The pharmacological properties of bufagin, its keeping qualities, its chemical purity and the consequent ease with which it lends itself to exact dosage are facts that urge a trial of this substance in therapeutics. The successful use of toad skins in the medicine of an earlier day also lends support to our suggestion.