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Optically active isomers that are not enantiomorphs (mirror images), for example, d-glucose and d-galactose.
References in periodicals archive ?
Hasegawa, "Determination of hexabromocyclododecane diastereoisomers and tetrabromobisphenol A in water and sediment by liquid chromatography/mass spectrometry," Analytical Sciences, vol.
catechu; these are diastereoisomers of the 5,7,3',4'-tetrahydroxyflavan-3-ol structure (Figs.
6n of 29 and a series of reflections between 25 and 28 [degrees] of 2 [theta], as typical of a mixture of diastereoisomers A and B (Yao et al.
Silymarin consists of at least seven flavonolignans, of which the most prevalent are the diastereoisomers silybin A and silybin B; silibinin consists only of silybin A and silybin B.
We were not able to separate the isomers present in the pheromone volatiles collected from females or synthetic stereoisomers with 2 different chiral columns because the enantiomers of branched aliphatic hydrocarbons do not possess a functional group that permits derivatized into diastereoisomers that could be separated by chromatographic methods or by spectroscopic techniques such as Nuclear Magnetic Resonance (Meierhenrich et al.
The hydroboration of 7a (diastereomeric mixture) resulted in 6- and 7-hydroxy methylacetals 8a and 9a, as a sum of 8 regio- and diastereoisomers (ratio of 8a and 9a was 4 : 1), and also 4% of the corresponding 6(S)-hydroxylactol 10.
However, this enzyme, termed organophosphorus acid anhydrolase (OPAA), hydrolyzes the relatively non-toxic pair of diastereoisomers, C([not equal to])P(+), more rapidly than the toxic pair C([+ or -])P(-) (1).