Several pharmaceutical formulations and supplements are manufactured with
racemate (DL-carnitine), although only the levorotatory form is biologically active (Sanchez-Hernandez et al., 2010a, 2010b; Dqbrowska & Starek, 2014).
A
racemate compound with a pair of cis/trans has DF=0.5 or 50%, while with two pairs, has DF=0.25 or 25% for each diastereomer.
The plasma concentration of free (Unbound) levobupivacaine is lower than that of bupivacaine
racemate, because of greater protein binding of the levorotatory enantiomer.
It should also be noted that a mismatch in the chemical shifts of the signals for each enantiomer with respect to
racemate is explained by different amounts of the sample compounds loaded into a vial and the shift reagent.
In SESA trial, edema was resolved in 98.72% patients after switching from
racemate amlodipine to S-AM [21].
The single crystal XRD also confirms the structure of iodo product 13 and indicates the product to be a
racemate of RandS isomers (figure 3).
1) from Cecropia moth and its structure was established by Trost by the synthesis of its
racemate. (5) Later studies revealed JHs to be a group of epoxy esters generated by homologation and epoxidation of methyl farnesoate.
To develop a single stereoisomer from a mixture that has already been studied non-clinically, an abbreviated, appropriate pharmacology/toxicology evaluation could be conducted to allow the existing knowledge of the
racemate available to the sponsor to be applied to the pure stereoisomer....
Werner, "From the
racemate to the eutomer: (S)-ketamine.