Do all carbonic chains have isomers? With a few exceptions...? Read on...?

Question

Hormones are organic compounds made of carbon chains, connected to hydrogen atoms and whatnots...

They also contain benzene in their chains. Anyway, since they're organic... can they have isomers?

I just think it'll be a little weird to have an isomer of estradiol, estrene (I think that's how you spell it), progesterone, testosterone, etc.

Speaking of hormones... since all steroids are carbonic chains, can they have isomers? What about lipids...?

I'm so damn confused! X-(

CALLING ALL BIOCHEMISTS! :-/

Answer 1

hormones are specific. if you just have a random carbon chain it can be any of various isotypes depending on the chain. hormones are locked into place and have specific steriochemistry (regio and site specific) or the body wouldn't recognise them.

Answer 2

Not all organic molecules have isomers. Isomerization requires a rearrangement of the molecule, a chiral carbon, or a double or triple bond, and non-symmetry about such a bond. This subject is really too involved to fully explain here. See the list of links at the following web page below.

Answer 3

Benzene isomers. II. 3,4-Dimethylenecyclobutene

BAW Coller, ML Heffernan and AJ Jones

Abstract

Theoretical considerations indicate that the electron distribution in 3,4,-dimethylenecyclobutene is non-uniform and a dipole moment of 0.71 D has been predicted by inclusion of non-neighbour core resonance integrals. Preliminary studies of the microwave spectrum of this compound provide a dipole moment of 0.618 ± 0.011 D. The term "pseudo-alternant" is proposed to describe this phenomenon. In the present paper additional physical and chemical properties of 3,4,-dimethylene- cyclobutene are described. The observed low-field proton chemical shifts for 3,4-dimethylenecyclobutene are not accounted for using a ring current model and a small calculated paramagnetic current indicates properties usually associated with Hückel 4n-hydrocarbons. A local anisotropy model provides a better account of the observed shift. The carbon-13- proton satellite spectrum of 3,4-dimethylenecyclobutene indicates similarities in the geometry of the four-membered ring to that in cyclobutene. In addition, infrared and ultraviolet spectra support the conclusion that this hydrocarbon be regarded as a cross-conjugated diene. A detailed discussion of the products arising from the bromination of 3,4-dimethylenecyclobutene under a variety of conditions indicates consecutive 1,4-addition of bromine across the four-membered ring, a property which has been associated with cross-conjugation. Hydrogenolysis, chlorination, iodination, and attempted Diels-Alder addition reactions are also described. 3,4-Dimethylenecyclobutene was prepared by the thermal rearrangement of hexa-1,5-diyne. The mechanisms of thermal and photolytic rearrangement of hexa-1,5-diyne are discussed using Woodward-Hoffmann postulates. 1,2-Dideutero-,1-ethyl-, and 1-n-propyl-3,4-dimethylenecyclobutene were also prepared by the thermal rearrangement of the corresponding diyne. In addition, the thermal rearrangement of hexa-1,5-diyne over the temperature range 290-700º to give variable quantities of 3,4-dimethylenecyclobutene, fulvene, and benzene is described. 3,4- Dimethylenecyclobutene is thermally rearranged to benzene at 680º.

Australian Journal of Chemistry 21(7) 1807 - 1826

Full text doi:10.1071/CH9681807
  


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Answer 4

i think they do have isomers... But hormones are very specific in their activities so only one of the two optical isomers can react with whatever in human bodies...