Ibuprofen enantiomer structure

Because the aldehyde group is an extremely versatile functionality, AH constitutes a useful entree into chiral biologically active compounds such as the nonsteroidal antiinflammatory drug (S)-naproxen (32), commonly called Aleve. Section 9-7-1 highlighted a racemic hydrofomylation that was a key step in the synthesis of ibu-profen. naproxen is quite similar to ibuprofen in structure, but the toxic nature of racemic Naproxen in the body demands that it be synthesized and administered as the much less toxic (S)-enantiomer. Scheme 12.14 shows a possible route to 32, first involving AH of the vinyl naphthalene in the presence of BINAPHOS (34, Fig. 12-6) to create the chiral branched aldehyde and then subsequent oxidative conversion of the aldehyde to the carboxylic acid.83 AH of vinylnaphthalene (33)... 

Many pharmaceutical preparations demand that a single enantiomer be used because one enantiomer is active and the other is not. Ibuprofen (see structure) is an anti-inflammatory drug (used to treat pain), and it is an exception because the body quickly racemizes either pure enantiomer. For this reason, racemic ibuprofen is used commercially. Draw both enantiomers and briefly comment on the specific rotation of the racemate. 

FIGURE 5.7. Molecular structure of ibuprofen enantiomers. (Advil is a registered trademark of Wyeth Consumer Healthcare, and Motrin is a registered trademark of McNeill-PPC Inc.)... 

Figure 5.5. Molecular structures of adrenaline enantiomers Figure 5.6. Molecular structures of thalidomide enantiomers Figure 5.7. Molecular structures of ibuprofen enantiomers Figure 5.8. Molecular structures of fluoxetine enantiomers...

B-8. The S enantiomer of ibuprofen is responsible for its pain-relieving properties. Which one of the structures shown is (S)-ibuprofen ... 

Nonsteroidal antiinflammatory drugs. Pirprofen, naproxen, ibuprofen, and keto-profen can occasionally cause microvesicular steatosis in humans (Bravo et al. 1997 Victorino et al. 1980 Danan et al. 1985 Dutertre et al. 1991). These NSAIDS have a 2-arylpropionate structure, with an asymmetric carbon, and exist as either the S(+)- or the R(—)-enantiomers. Only the S(+)-enantiomer inhibits prostaglandin synthesis, whereas only the R( )-enantiomer is converted into the acyl-CoA derivative. However, both the S(+)-enantiomer and the R( )-enantiomer of ibuprofen inhibit the p-oxidation of medium- and short-chain fatty acids (Freneaux et al. 1990). Pirprofen, tiaprofenic acid, and flurbiprofen also inhibit mitochondrial p-oxidation (Geneve et al. 1987a). 

There is an important group of analgesic (pain-killing) drugs, such as ibuprofen, based on the aryl-propionic acid structure. Ibuprofen can be bought over the counter in chemists shops as Nurofen. Only the (S)-enantiomer of ibuprofen is an effective painkiller but the compound is administered as the racemate. The body does the rest, racemizing the compound by enolizing it. 

Concerning the values of standard chemical adsorption potential (A/ra), the S-propranolol antipode possesses a higher affinity for the adsorbent than its enantiomer but taking into account the results obtained with other chiral species such as ibuprofen, adsorption of propranolol on this stationary phase is governed not only by the moieties containing the chiral carbon, but also primarily by the aromatic moieties in the structure of chiral selector. 

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