Retinol acetate

C H 7N02 2164-42-3) see Guanoxan ll,12-dihydro-ll-(phenylsulfonyl)retinol acetate... 

Stohs, S.J., Hassan, M.Q. and Murray, W.J. (1984). Effects of a-tocopherol and retinol acetate on TCDD-mediated changes in lipid peroxidation, glutathione peroxidase activity and survival. Xenobiotica 14, 533-537. 

Synthetic 13-m-retinoic acid not only inhibited the incidence but also reduced the severity of bladder neoplasms induced by the intravesical administration of MNU of female Wister-Lewis rats [113]. In an experimental model with mice treated with TV-butyl-A -(4-hydroxybutyl)-nitrosamine (OH-BBN), retinoic acid (Re5), 13-cw-retinoic acid, and retinol acetate (Re2) show chemopreventive activity. In addition, a quite large number of synthetic -alkyl amide derivatives of Re2 have a greater activity to toxicity ratio than 13-cw-retinoic acid [113]. 

RETINOL ACETATE RETINYL ACETATE all-trans-RETINYL ACETATE trans-VITAMIN A ACETATE VITAMIN A ALCOHOL ACETATE... 

Mercier, T., Honikman-Leban, E., Chaumontet, C., Martel, R, and Shahin, M. M. (1993). Studies on the modulating effects of retinoic acid and retinol acetate using dye transfer and metabolic cooperation assays. Fundam Appl Toxicol 21, 270-276. 

Similarly, the retinol acetate was taken up for dipole moment and fluorescence studies [69]. The change in dipole moment upon excitation was found to be 2.7D for retinol acetate. It was interpreted that the change in dipole moment upon excitation makes the retinol acetate molecule to interact more efficiently... 

Shelley, R. Price, J.C. Jun, H.W. Cadwallader, D.E. Capomacchia, A.C. Improved and rapid high-performance liquid chromatographic assay for 13-cis-retinoic acid or all-trans-retinoic acid. J.Pharm.Sci., 1982, 71, 262-264 [rat serum extracted isotretinoin, retinol acetate, tretinoin, vitamin A pharmacokinetics LOQ 100 ng mL]... 

Total synthesis is applied for carotenoids on a lO t scale per year. One usually starts with the cheapest carbonyl components (formaldehyde, acetone) and carbanions (acetylide, acetoacetate, cyanide, Wittig ylides) available. A typical industrial synthesis of retinol acetate (vitamin A) is outlined in Scheme 5.3,1. 

In this study, the product selectivity and product distribution following photooxidation was found to depend on the zeolite used. All of the zeolites that exhibited a loss of product selectivity for toluene photooxidation are susceptible to acid site formation during cation exchange and subsequent pretreatment or calcination. The colorimetric test described by Ramamurthy and coworkers was utilized to detect Bransted acid sites in the zeolites used in this study (10, 11). The colorimetric test is based on differences in the electronic absorption properties of protonated and unprotonated forms of probe molecules, such as retinol and retinol acetate. Both retinol and retinol acetate form a blue retinyl cation in an acid solution. The zeolites were activated by heating to 300°C under vacuum for approximately 12 hrs. Samples of BaZSM-5 (12) and CaY both turned dark blue when a dilute solution of retinol was added to the activated zeolite indicating the presence of Bronsted acid sites. Activated NaZSM-5 turned blue and activated BaY zeolite turned light blue... 

For the side-chain of retinol acetate, there are four options to cut the double bond system retrosyntheticaUy (Fig. 7.28). [55] Four double bonds give theoretically rise to 16 stereoisomers. Knowing that disubstituted (Z)-double bonds, as in jS-carotene, are isomerised under milder conditions than trisubstituted ones, limits the retrosynthetic choices. 

The retrosynthetic analysis of retinol acetate reveals eight options for the carbonyl building block and its matching phosphorane. 

The Wittig reaction of the /1-ionylidenethyltriphenylphosphonium salt with ( )-4-acetoxy-2-methylbut-2-enal leads in high yields directly to ( /Z)-retinol acetate, which subsequently has to be isomerised and crystallised. [55]... 

An alternative /1-carotene process, currently in use at BASF, starts from retinol acetate [55, 58], which is reacted with triphenylphosphane in the presence of an add to give the C2o-phosphonium salt. Partial alkaline oxidation with hydrogen peroxide leads directly to ( /Z)-jS-carotene, which is then isomerised to its (aU )-form in an overall yield of around 70 %. 

CAS 127-47-9 EINECS/ELINCS 204-844-2 Synonyms Acetic acid, retinyl ester Retinol acetate all-trans-Retinyl acetate Vitamin A acetate trans-Vitamin A acetate Vitamin A alcohol acetate Definition Ester of retinol and acetic acid Empiricai C22H32O2... 

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