Dehydro retinol

Modified Dose Response Dehydro retinol/retinol ... 

Ethers and esters derived from the alcohol also show activity in vivo. The ring structure of retinol ((i-ionone), or the more unsaturated ring in 3-dehydroretinol (dehydro-P-ionone), is essential for activity hydrogenation destroys biological activity. Of all known derivatives, all-/ran,v-retinol and its aldehyde, retinal, exhibit the greatest biological potency in vivo 3-dehydroretinol has about 40% of the potency of all-bms-retinol. 

The term Vitamin A" is here collectively used to encompass (all E)-retinol and (all E)-retinal, also their 3-dehydro-derivatives and double bond isomers, and retinol esters. 

An interesting isocratic solvent system, 22/71/4/2/1 DCM/acetonitrile/ methanol/water/propionic acid, was used to elute carotenoids, retinol, retinal, and their dehydro analogs (21 compounds total) on a Cig column (A = 352nm or 450ran) from fish serum and eggs [771]. A table was generated that contained retention times and W values for all compounds. Elution was complete in just under 60 min, with retinyl palmitate and a- and j -carotene the only analytes with retention times of >20 min. Standards of 2pg/mL were used and easily detected. Baseline resolution was not achieved between all analyte pairs. 

F Zonta, B Stancher. High-performance liquid chromatography of retinals, retinols (vitamin Ai) and their dehydro homologues (vitamin Aj) improvements in resolution and spectroscopic characterization of the stereoisomers. J Chromatogr 301 65-75, 1984. 

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