A secosteroid () is a type of

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 ...

with a "broken" ring. The word ''secosteroid ''derives from the Latin verb ''secare'' meaning "to cut", and 'steroid'. Secosteroids are alternatively described as a subclass of steroids; ; or derived from steroids. Types or subclasses of secosteroids are defined by the carbon atoms of the parent steroid skeleton where the ring cleavage has taken place. For example, 9,10-secosteroids derived from cleavage of the bond between carbon atoms C9 and C10 of the steroid B-ring (similarly 5,6-secosteroids, 13,14-steroids, etc.). The prototypical secosteroid is

cholecalciferol Cholecalciferol, also known as vitamin D3 and colecalciferol, is a type of vitamin D that is made by the skin when exposed to sunlight; it is found in some foods and can be taken as a dietary supplement. Cholecalciferol is made in the skin f ...

(vitamin D₃). Some

nonsteroidal estrogen A nonsteroidal estrogen is an estrogen with a nonsteroidal chemical structure. The most well-known example is the stilbestrol estrogen diethylstilbestrol (DES). Although nonsteroidal estrogens formerly had an important place in medicine, they hav ...

s, like

doisynolic acid Doisynolic acid is a synthetic, nonsteroidal, orally active estrogen that was never marketed. The reaction of estradiol or estrone with potassium hydroxide, a strong base, results in doisynolic acid as a degradation product, which retains high ...

and

allenolic acid Allenolic acid, or allenoic acid, is a synthetic, nonsteroidal estrogen discovered in 1947 or 1948 that, although studied clinically, was never marketed. It is an open-ring or seco- analogue of steroidal estrogens like estrone and equilenin. Th ...

, are also secosteroids or secosteroid-like compounds.

References

External links

* {{Steroid classification