R/S enantiomers

R, S - enantiomers of a racemic substrate P, Q - enantiomers of a product Yieid Yieid ... 

The first exemplary problem is the separation of a racemic mixture EMD53986 (R S-enantiomers = 1 1) on the chiral stationary phase Chiralpak AD from Daicel (20 pm particle diameter) (Tab. 7.1). 

For acyclic imines, note that interchange of Ri and R2 in the transition structure is equivalent to an E/Z isomerization of the educt. Reduction of cyclohexyl methyl A -benzyl imine, using a stoichiometric amount of catalyst affords a 92 8 R/S enantiomer ratio that is identical to the 92 8 E/Z ratio of the educt i.e., the reaction... 

Mefloquine 274 is a useful alternative treatment agent for Plasmodium vivax malaria and Plasmodium falciparum malaria in areas, where chloroquine is still recommended as the first-hne therapeutic agent.Mefloquine is a chiral molecule with two asymmetric carbon centers, and it exists as a mixture of diastereomers. The drug is currently manufactured and sold as a racemate of the (+1—) R,S enantiomers by Hoffman-LaRoche. The (+) enantiomer is more effective in treating malaria, and the (—) enantiomer specifically binds to adenosine receptors in the central nervous system, which may explain some of its psychotropic effects.It is not known whether mefloquine can be transformed into its stereoisomer in vivo. 

DPX-MP062 - indoxacarb 75 25 mixture of R S enantiomers (the (S)-isomer, DPX-KN128, is shown)... 

Nevirapine and efavirenz increase the R/S enantiomer concentration ratio, hence increasing the therapeutic effects of methadone, which are almost exclusively mediated by the R enantiomer, as has been shown in five patients taking nevirapine and nine taking efavirenz [97 ]. These interactions are thought to be mediated by induction of CYP2B. 

---