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Optically active isomers that are not enantiomorphs (mirror images), for example, d-glucose and d-galactose.
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In this work, a sensitive and selective GC-NCI-MS method has been developed to analyze thirty-six synthetic cathinone compounds after their conversion into diastereoisomers through the derivatization reaction with L-TPC.
ref.] medium Calculated calculated dr (b) anti : from MAD syn experimental dr (c) [%] M062X/6- Gas/neat 5 : 95 57 46.5 31g(d) Water 29 : 71 36 BH&HLYP/6- Gas/neat 10 : 90 10 9 31g(d) Water 37 : 63 8 B3LYP/6- Gas/neat 11 : 89 0 2 31G(d) Water 38 : 62 4 B3LYP/6- Gas/neat 9 : 91 20 18 31G(d,p) Water 35 : 65 16 B3LYP/6-311 Gas/neat 16 : 84 54 33 ++G(3d,3p) Water 36 : 64 12 BH&HLYP/ Gas/neat 9 : 91 20 12 cc-pVDZ Water 40 : 60 4 (a) Diastereoisomer ratio of anti to syn isomers as indicated by NMR analysis.
Hasegawa, "Determination of hexabromocyclododecane diastereoisomers and tetrabromobisphenol A in water and sediment by liquid chromatography/mass spectrometry," Analytical Sciences, vol.
However, the molecule possesses two chiral centers at C-2 and C-3 resulting in four possible diastereoisomers (astilbin, neoastilbin, isoastilbin and neoisoastilbin).
Biotransformation enzymes and thyroid axis disruption in juvenile rainbow trout (Oncorhynchus mykiss) exposed to hexabromocyclododecane diastereoisomers. Environ Sci Technol 42:1967-1972.
It is postulated that the glucose a-anomers bind faster than the [beta\-anomers, but the overall response is poor because the relative abundance of [alpha]-anomers is low and interconversion between the different diastereoisomers is slow.
The Diels-Alder addition of PTAD to the exocyclic diene in 25OHD produced a pair of diastereoisomers (Fig.
Such adducts, obtained as a pair of diastereoisomers, rearomatize by a variety of pathways which are being elucidated.
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.