Patent ID: 8507532

Claim:
A method, comprising: providing a composition including a stereoisomeric mixture of a compound having the following structure: wherein the mixture is defined by a first pair of diastereomers and a second pair of diastereomers, the first pair of diastereomers being defined by {(R)-1-[6-(triflouromethyl)pyridin-3-yl]ethyl}-(R)-(methyl)oxido-λ 4 -sulfanylidenecyanamide and {(S)-1-[6-(triflouromethyl)pyridin-3-yl]ethyl}-(S)(methyl)oxido-λ 4 -sulfanylidenecyanamide and the second pair of diastereomers being defined by {(R)-1-[6-(triflouromethyl)pyridin-3-yl]ethyl}-(S)-(methyl)oxido-λ 4 -sulfanylidenecyanamide and {(S)-1-[6-(triflouromethyl)pyridin-3-yl]ethyl}-(R)-(methyl)oxido-λ 4 -sulfanylidenecyanamide; and heating the composition to convert at least a portion of the second pair of diastereomers to the first pair of diastereomers.