2- Hexenal, trans-4-hydroxy

ACETATE AND ALDEHYDES OR KETONES ETHYL 1-HYDROXYCYCLO-HEXYLACETATE, 53, 66 2- (Hydroxymethylene)cyclohexanone with p-toluenesulfonyl azide to give 2-diazocyclo-hexanone, 51, 86 y-HYDROXY-ct, (3-UNSATURATED ALDEHYDES VIA 1,3-BIS(METHYL-THIO) ALLYLLITHIUM trans-4-HYDROXY-2-HEXENAL, 54, 19... 

D. trans-4-Hydroxy-2-hexenal. In a 500-ml., one-necked flask containing a Teflon -coated magnetic stirring bar is placed 3.85 g. (0.02 mole) of l,3-bis(methyIthio)-l-hexen-4-ol, 80 ml. of tetrahydrofuran (Note 11), and 6.00 g. (0.06 mole) of powdered calcium carbonate. The mixture is stirred, and a solution of 16.4 g. (0.06 mole) of mercuric chloride in 140 ml. of tetrahydrofuran and 40 ml. of water is added. The mixture is stirred and heated at 50-55° with a water bath for 15... 

Fluoroethylene ozonide, 0752 /rMaleic anhydride ozonide, 1406 f 2-Methyl-1,3-butadiene, Ozone, 1893 3-Methyl-l,2,4-trioxolane, 1235 trans-2-Pentene ozonide, 1982... 

Additional aldehydes and ketones were also included in the U.S. Nationwide Occurrence Study dimethylglyoxal (2,3-butanedione), cyanoformaldehyde, 2-butanone (methyl ethyl ketone), trans-2-hexanal, 5-keto-l-hexanal, and 6-hydroxy-2-hexanone [11, 13]. Dimethylglyoxal was the most consistently detected of these carbonyl compounds (up to 3.5 pg/L) and was found at higher levels in plants using ozone. Maximum levels of 0.3, 5.0, and 0.7 pg/L were observed for cyanoformaldehyde, 2-butanone, and trans-2-hexenal, respectively 6-hydroxy-2-hexanone and 5-keto-1 -hexanal were only detected in early stages of treatment, and not in finished waters. 

In relation to cancer, there is some evidence that highly oxidized and heated fats may have carcinogenic characteristics. HNE (4-hydroxy-2-frans-nonenal), a secondary lipid peroxidation product derived from linoleic acid oxidation, has assumed particular interest because it has shown cytotoxic and mutagenic properties. Its toxicity, as well other secondary lipid peroxidation products (HHE 4-hydroxy-2-frans-hexenal and HOE 4-h yd roxy-2-trans-oc ten al), is explained through the high reactivity with proteins, nucleic acids, DNA, and RNA. Research links them to different diseases such as atherosclerosis, Alzheimer s, and liver diseases (Seppanen and Csallany, 2006). Research is rapidly progressing, but results are still not conclusive. 

Winter CK, Segall HJ, Haddon WF. 1986. Formation of cyclin adducts of deoxyguanosine with the aldehydes trans-4-hydroxy-2-hexenal and trans-4-hydroxy-2-nonenalinjviim. Cancer Res 46 5682-5686. 

Another important example of the Michael addition in biochemistry and molecnlar biology is the reaction of 4-hydroxynon-2-enal with amines and snlfydryl gronps (Winter, C.K., Segall, H.J., and Haddon, W.F., Formation of cyclic addncts of deoxygnanosine with the aldehyde trans-4-hydroxy-2-hexenal and fran.y-4-hydroxy-2-nonenal in vitro. Cancer Res. 46, 5682-5686, 1986 Sayre, L.M., Arora, P.K., Iyer, R.S., and Salomon, R.G., Pyrrole formation from 4-hydroxynonenal and primary amines, Chem. Res. Toxicol. 6, 19-22, 1993 Hartley, D.P, Ruth, J.A., and Petersen,... 

Tetrahydro-4-hydroxy-2-vinylfuran (2) can be prepared from 4-acetoxy-5-hexen-l,2-diol (I) with high 1,3-asymmetric induction via nucleophilic displacement on the palladium allyl complex, followed by elimination of a hydride. Thus, treatment of 1 with (dba),Pd2-chloroform and triphenylphosphane at 20 °C for 3 hours gives the tetrahydrofuran in 95 % yield and a 91 9 dia stereomeric ratio, On the basis of mechanistic considerations, the major isomer is assigned trans 1. 

Over 300 diol metabolites are known.8 Several diols and some secondary synthons derived from them have recently become commercially available Eastman Fine Chemicals, Genencor (1 S-cis)-3-Chloro-3,5-cyclohexadiene-1,2-diol, (1 S-cis)-3-bromo-3,5-cyclohexadiene-1,2-diol, (1 S-cis)-3-iodo-3,5-cyclohexadiene-1,2-diol, (5S-cis)-5,6-dihydroxy-1,3-cyclohexadiene-1 -carbonitrile, cis-2R,3S-2,3-dihydroxy-2,3-dihydrobenzonitrile acetonide, (1R-cis)-1,2-dihydro-1,2-naphthalenediol, (1R-cis)-1,2,3,4-tetrahydro-1,2-naphthalenediol, (4S-trans)-4,5-dihydroxy-3-oxo-1 -cyclo-hexene-1-carboxylic acid, furo[3,4-d]-1,3-dioxol-4(3aH)-1 -dihydro-6-hydroxy-2,2-dimethyl-[3aR-(3aa,6aa)]. 

H J COOH h3co T och3 ( T S, PICsHsIs 6-[ cis-5-Hydroxy-cis-3-methoxy- trans-2-( 3-methoxy-l-octenyl) -cyclopen-tyl -4-hexen-sdure-lacton 90 192... 

Curcumin is not water-soluble, but it is soluble in ethanol or in dimethylsulfoxide. The degradation kinetics of curcumin under various pH conditions and the stability of curcumin in physiological matrices have been established. When curcumin was incubated in O. IM phosphate buffer and semm-free medium (pH 7.2 at 37°C), about 90% decomposed within 30min. A series of pH conditions ranging from 3 to 10 were tested, and the results showed that decomposition was pH-dependent and occurred faster at neutral-basic conditions. It is more stable in cell culture medium containing 10% fetal calf seram and in human blood. Less than 20% of curcumin decomposed within Ih, and after incubation for 8h, about 50% of curcumin still remained. Trans-6-(4 -hydroxy-3 -methoxyphenyl)-2,4-dioxo-5-hexenal was predicted to be the major degradation product, and vanillin, feralic acid, and feraloyl methane were identified as minor degradation products. The amount of vanillin increased with incubation time. 

A series of alkanals and alkenals, degradation products of polyunsaturated fatty acids, were sqiarated as their dabsylhydrazine derivatives on a Cjg column (2 = 436nm) using a 60-min 40/60-> 80/20 acetonitrile/water gradient [917]. Acrolein, propionaldehyde, crotonaldehyde, butyraldehyde, 4-hydroxy-2-nonenal, malonaldehyde, fra/w-2-pentenal, hexanal, heptanal, tmns-2-octena, octanal, trans-2-nonenal, and nonanal were baseline resolved. When malonaldehyde and trans-2-hexenal were included in the set, they co-eluted with pentanal. Peak shapes were excellent and detection limits of 5 ng injected (S/N = 4) were reported. 

---