Category:TP3V

Hormonal Classes

Estranes (C18)

The backbone of estrogens, the hormones responsible for female reproductive organs and secondary sex characteristics. The original spelling was 'oestrogen'. Major namings are:

estrogen ... estra-1,3,5(10)-triene
estrone ... 3-hydroxyestra-1,3,5(10)-triene-17-one
estradiol ... estra-1,3,5(10)-triene-3,17β-diol
estriol ... estra-1,3,5(10)-triene-3,16α,17β-triol
equine estrogens ... estra-1,3,5(10),7-tetraene and estra-1,3,5,7,9-pentaene series

Androstanes (C19)

The backbone of male hormone testosterones. Major namings are:

etianic acids (C20) ... androstane-17-carboxylic acids and their derivatives
D-homoandrostanes (C20) ... ring D is expanded by including C-17a carbon.

Pregnanes (C21)

The backbone of pregnancy hormone progesterone and the majority of corticosteroids. It is the largest single group of steroids. Major namings are:

progesterone ... pregn-4-ene-3,20-dione
17α-ethynylandrostane ... 17α-pregn-20-yne
19-norpregnane (C20) ... 17α-ethynylestrane, 19-nor-17α-pregn-20-yne

17α-pregnanes are sometimes called 17α-vinyl- and 17α-ethyl-androstanes.

Cholanes (C24)

The backbone of bile acids, i.e., 5β-cholan-24-oic acids with hydroxyl substitution at C-3.

primary bile acids ... cholic acid and chenodeoxycholic acid are biosynthesized directly from cholesterol.
secondary bile acids ... deoxycholic acid and lithocholic acid are generated by intestinal bacteria.
24-norcholan-23-oic acids ... loss of one carbon side chain
23,24-dinorcholan-22-oic acids ... loss of two carbon side chains

C/D cis Classes

Cardenolides (C23)

See TP3P.

Bufanolides (C24)

See TP3O.

Steroidal Classes

Sterols (C27)

The sterol backbone contains a β hydroxyl group at C-3 and side chains of 8-10 carbons at C-17. They are important membrane constituents in addition to their biologically activity.
Major categories are:

cholestane ... androstane structure with a branched C8 chain at the 17β-position
norcholestane ... cholestane lacking one of 27 carbons
ergostane and campestane ... 24β- and 24α-methylcholestane
poriferastane and stigmastane ... 24β- and 24α-ethylcholestane
vitamin D2 ... 9,10-secoergonstane derivatives
vitamin D3 ... 9,10-secocholestane derivatives
lumistane ... 9β,10α-ergosta-5,7-diene

Ecdysteroid (C27)

See TP3I.

Spirostans and furostans (C27)

Furostan has the additional epoxy ring E. Spirostan has another epoxy ring F, which is perpendicular to the planar orientation of rings A-E. The omission of a terminal 'e' from spirostans and furostans indicates that they are not hydrocarbons. (However, the last 'e' is needed if a consonant follows.)
Major categories are: