With the number of current pharmaceuticals currently being marketed as racemic mixtures, it is likely that patentability will continue to be debated in the near future.
42.
As both methyl groups are attached to a stereogenic center, two enantiomers ( R, R and S, S ) are formed, normally as a racemic mixture.
43.
In the meanwhile the ( R )-alcohol remains in solution unaffected and is recycled back to the racemic mixture by epimerization with hydrochloric acid in toluene.
44.
In racemic mixtures the odor is floral and citrus while epimerized mixtures exhibit a dense fatty floral odor with odor recognition thresholds of 15 parts per billion.
45.
An example is eszopiclone ( Lunesta ), which is enantiopure and therefore administered in doses that are exactly 1 / 2 of the older, racemic mixture called zopiclone.
46.
Ofloxacin is a racemic mixture, which consists of 50 % levofloxacin ( the biologically active component ) and 50 % of its mirror image or enantiomer dextrofloxacin.
47.
Methylphenidate was originally available as an immediate-release racemic mixture formulation under the Novartis trademark name Ritalin, although a variety of generics are now available, some under other brand names.
48.
The " meso " compound must not be confused with a 50 : 50 racemic mixture of the two optically-active compounds, although neither will rotate light in a polarimeter.
49.
The remainder of the sample is a racemic mixture of the enantiomers ( 30 % R and 30 % S ), which has no net contribution to the observed rotation.
50.
The reagents of, and the reactions that produce, racemic mixtures are said to be " not stereospecific " or " not stereoselective, " for their indecision in a particular stereoisomerism.
