adjective
definition
Containing equal amounts of dextrorotatory (D) and levorotatory (L) stereoisomers and therefore not being optically active
Examples of racemic in a Sentence
Since the molecule contains an asymmetric carbon atom, the acid exists in three forms, one being an inactive "racemic" mixture, and the other two being optically active forms. The inactive variety is known as paramandelic acid.
Their constitution follows from their formation from dibromosuccinic acid and from their synthesis from glyoxal cyanhydrin, these two methods producing the inactive racemic form which may then be split into the active components.
By mixing equal quantities of the two forms in aqueous solution heat is evolved and racemic acid, (C4H606)2.2H20, is obtained.
The a-propyl piperidine so obtained is the inactive (racemic) form of conine, and it can be resolved into the dextroand laevo-varieties by means of dextro-tartaric acid, the d-conine d-tartrate with caustic soda giving d-conine closely resembling the naturally occurring alkaloid.
The racemic trans-acid is produced by the reduction of the dihydrobromide of A 4 -tetrahydrophthalic acid or dihydrophthalic acid.
The trans-acid is a racemic compound, which on heating with acetyl chloride gives the anhydride of the cis-acid.
This is known as a racemic mixture and it is optically inactive due to one isomer canceling out the optical effect of the other.
This property has been used to separate racemic mixtures.
Like AMO, it oxidizes propene to epoxypropane, but yields a racemic product.
Four acids of this composition are known, namely dextroand laevo-tartaric acids, racemic acid and mesotartaric acid, the two last being optically inactive (see Stereo-Isomerism).
Absence of rotary power when asymmetric carbon atoms are present, may be caused by an internal compensation within the molecule as with the inactive tartaric acid (mesotartaric acid), or may be due to the fact that the compound is an equimolecular mixture of leftand right-hand varieties, this being the case with racemic acid that was broken by Louis Pasteur into laevoand dextro-tartaric acid (see Stereo-Isomerism).
The cost in Colombia is 40% higher, than racemic bupivacaine.
Recent research work has been directed at the toxicity associated with the levo isomer, and how it compares with the racemic preparation.
Aerosolized racemic epinephrine as well as oral dexamethasone (a steroid) may be used to help shrink the upper airway swelling.