The reduction of S,S-2-methylsulfanyl-2methylsulfinyl-1-indanone (diastereoisomer
mixture 10:0.8) using NaB[H.sub.4] was performed in metanol as solvent, isolating a unique diastereoisomer
(10) in 70% yield and 90% of diastereomeric excess (Scheme 5).
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.
Hasegawa, "Determination of hexabromocyclododecane diastereoisomers
and tetrabromobisphenol A in water and sediment by liquid chromatography/mass spectrometry," Analytical Sciences, vol.
(8) The peaks in the TIC are sometimes split since tetravalent phosphorus atom is asymmetric and if one (or more) carbon atoms are also asymmetric, two (or a power of two) peaks of diastereoisomers
with different RI but the same or almost the same mass spectra are observed (soman is a typical example).
Vessman, "Direct separation of captopril diastereoisomers
including their rotational isomers by RP-LC using a teicoplanin column," Journal of Pharmaceutical and Biomedical Analysis, vol.
catechu; these are diastereoisomers
of the 5,7,3',4'-tetrahydroxyflavan-3-ol structure (Figs.
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).
The Diels-Alder addition of PTAD to the exocyclic diene in 25OHD produced a pair of diastereoisomers
Dietary intake of hexabromocyclododecane diastereoisomers
([alpha]-, [beta]-, and [gamma]-HBCD) in the Belgian adult population.