Search results
Results from the WOW.Com Content Network
Examples of absolute configuration of some carbohydrates and amino acids according to Fischer projection (D/L system) and Cahn–Ingold–Prelog priority rules (R/S system) The R/S system is an important nomenclature system for denoting enantiomers. This approach labels each chiral center R or S according to a system by which its substituents ...
There are three common naming conventions for specifying one of the two enantiomers (the absolute configuration) of a given chiral molecule: the R/S system is based on the geometry of the molecule; the (+)- and (−)- system (also written using the obsolete equivalents d- and l-) is based on its optical rotation properties; and the D/L system is based on the molecule's relationship to ...
Meaning Origin language and etymology Example(s) dacry(o)-of or pertaining to tears: Greek δάκρυ, tear dacryoadenitis, dacryocystitis-dactyl(o)-of or pertaining to a finger, toe Greek δάκτυλος (dáktulos), finger, toe dactylology, polydactyly: de-from, down, or away from Latin de-dehydrate, demonetize, demotion dent-
a.s., as, AS left ear auris sinistra a.u., au, AU both ears together or each ear aures unitas or auris uterque b.d.s, bds, BDS 2 times a day bis die sumendum b.i.d., bid, BID twice a day / twice daily bis in die gtt., gtts drop(s) gutta(e) h., h hour: hora: qhs, h.s., hs at bedtime or half strength quaque hora somni ii two tablets duos doses iii
The S enantiomer causes birth defects, while the R enantiomer is effective against morning sickness. Thalidomide: Thalidomide is racemic. One enantiomer is effective against morning sickness, whereas the other is teratogenic. However, the enantiomers are converted into each other in vivo. [18]
It is a racemic mixture of (R)- and (S)-enantiomers. [6] The (R)-enantiomer is -1-aminoindan, which has pharmacological activity and is an active metabolite of the antiparkinsonian agent rasagiline. [2] [4] [5] A number of notable 1-aminoindane derivatives exist. These include the following:
As indicated earlier, the (R)- enantiomer is the pharmacologically active diuretic. Like most other diuretics, the (R)-isomer possesses an undesirable side-effect of retaining uric acid. But the (S)-enantiomer, the distomer , has the property of assisting uric acid secretion (uricosuric effect), and, therefore, antagonizing the undesirable side ...
The ideal kinetic resolution is that in which only one enantiomer reacts, i.e. k R >>k S. The selectivity (s) of a kinetic resolution is related to the rate constants of the reaction of the R and S enantiomers, k R and k S respectively, by s=k R /k S, for k R >k S. This selectivity can also be referred to as the relative rates of reaction.