Description
Ibuprofen is a non-steroidal anti-inflammatory drug with diverse biochemical actions, most notably inhibiting COX-1 and COX-2 (IC
50s = 2.6 and 1.53 μM, respectively). It is commonly synthesized as a racemic mixture of (S) and (R) isomers (Item No. item
70280). (R)-Ibuprofen is an enantiomer that is generally not considered a COX inhibitor and is instead thought to be involved in pathways of lipid metabolism as it is incorporated into triglycerides along with fatty acids. The (R) enantiomer can, however, inhibit NF-κB activation (IC
50 = 121.8 μM) in response to T-cell stimulation as well as block superoxide formation, β-glucuronidase release, and LTB
4 generation by stimulated neutrophils (IC
50 values range from 40-100 μM). 50-60% of (R)-ibuprofen is inverted to (S)-ibuprofen in humans after oral administration.
Purification Methods
Crystallise the (+) and (-) acids from EtOH or aqueous EtOH. The racemate which crystallises from pet ether with m 75-77o is sparingly soluble in H2O and has IR (film) 1705 (C=O), 2300—3700 (OH broad)cm-1. It is used as a non-steroidal anti-inflammatory. [Shiori et al. J Org Chem 43 2936 1978, Kaiser et al. J Pharm Sci 65 269 1976, J Pharm Sci 81 221 1992, Freer Acta Cryst (C) 49 1378 1993 for the (S+)-enantiomer.]
