Bufadienolide is a chemical compound with

steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...

structure. Its derivatives are collectively known as bufadienolides, including many in the form of bufadienolide

glycosides In chemistry, a glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. ...

(bufadienolides that contain structural groups derived from sugars). These are a type of

cardiac glycoside Cardiac glycosides are a class of organic compounds that increase the output force of the heart and decrease its rate of contractions by inhibiting the cellular sodium-potassium ATPase pump. Their beneficial medical uses are as treatments for c ...

, the other being the

cardenolide A cardenolide is a type of steroid. Many plants contain derivatives, collectively known as cardenolides, including many in the form of cardenolide glycosides (cardenolides that contain structural groups derived from sugars). Cardenolide glycoside ...

glycosides. Both bufadienolides and their glycosides are

toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst ...

; specifically, they can cause an

atrioventricular block Atrioventricular block (AV block) is a type of heart block that occurs when the electrical signal traveling from the atria, or the upper chambers of the heart, to ventricles, or the lower chambers of the heart, is impaired. Normally, the sinoatr ...

bradycardia Bradycardia (also sinus bradycardia) is a slow resting heart rate, commonly under 60 beats per minute (BPM) as determined by an electrocardiogram. It is considered to be a normal heart rate during sleep, in young and healthy or elderly adults, a ...

(slow heartbeat),

ventricular tachycardia Ventricular tachycardia (V-tach or VT) is a fast heart rate arising from the lower chambers of the heart. Although a few seconds of VT may not result in permanent problems, longer periods are dangerous; and multiple episodes over a short period ...

(a type of rapid heartbeat), and possibly lethal

cardiac arrest Cardiac arrest is when the heart suddenly and unexpectedly stops beating. It is a medical emergency that, without immediate medical intervention, will result in sudden cardiac death within minutes. Cardiopulmonary resuscitation (CPR) and possib ...

Etymology

The term derives from the toad genus ''

Bufo ''Bufo'' is a genus of true toads in the amphibian family Bufonidae. As traditionally defined, it was a wastebasket genus containing a large number of toads from much of the world, but following taxonomic reviews most of these have been moved t ...

'' that contains bufadienolide glycosides, the suffix ''-adien-'' that refers to the two double bonds in the lactone ring, and the ending ''-olide'' that denotes the

lactone Lactones are cyclic carboxylic esters, containing a 1-oxacycloalkan-2-one structure (), or analogues having unsaturation or heteroatoms replacing one or more carbon atoms of the ring. Lactones are formed by intramolecular esterification of the co ...

structure. Consequently, related structures with only one double bond are called ''bufenolides'', and the

saturated Saturation, saturated, unsaturation or unsaturated may refer to: Chemistry * Saturation, a property of organic compounds referring to carbon-carbon bonds ** Saturated and unsaturated compounds **Degree of unsaturation ** Saturated fat or fatty ac ...

equivalent is ''bufanolide''. Bufanolide structure

Classification

According to

MeSH A mesh is a barrier made of connected strands of metal, fiber, or other flexible or ductile materials. A mesh is similar to a web or a net in that it has many attached or woven strands. Types * A plastic mesh may be extruded, oriented, ex ...

, bufadienolides and bufanolides are classified as follows: *

Polycyclic compound In the field of organic chemistry, a polycyclic compound is an organic compound featuring several closed rings of atoms, primarily carbon. These ring substructures include cycloalkanes, aromatics, and other ring types. They come in sizes of t ...

s **

Steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...

s ***

Cardanolide Cardanolide is a steroid with a molecular weight of 344.531. See also * Cardiac glycoside Cardiac glycosides are a class of organic compounds that increase the output force of the heart and decrease its rate of contractions by inhibiting the ...

s ****

Cardiac glycoside Cardiac glycosides are a class of organic compounds that increase the output force of the heart and decrease its rate of contractions by inhibiting the cellular sodium-potassium ATPase pump. Their beneficial medical uses are as treatments for c ...

s *****Bufanolides (includes bufenolides, bufadienolides, bufatrienolides) ******

Proscillaridin Proscillaridin is a cardiac glycoside, a kind of drug that can be used in the treatment of congestive heart failure and cardiac arrhythmia (irregular heartbeat). It is of the bufanolide type and can be obtained from plants of the genus ''Scilla'' ...

******

Daigremontianin Daigremontianin is a bufadienolide. Bufadienolides are steroids and cardiac glycoside aglycones (meaning that they bind with carbohydrates to form cardiac glycosides) that are similar to cardenolides, differing only in the structure of the C-17 s ...

*****

Cardenolide A cardenolide is a type of steroid. Many plants contain derivatives, collectively known as cardenolides, including many in the form of cardenolide glycosides (cardenolides that contain structural groups derived from sugars). Cardenolide glycoside ...

Etymology

Classification

References

Further reading