Showing papers on "Brucine published in 1970"
TL;DR: In this article, β-Chlorolactic acid was condensed with toluene-α-thiol to give 2-hydroxy-3-benzylthiopropanoic acid.
Abstract: β-Chlorolactic acid was condensed with toluene-α-thiol to give 2-hydroxy-3-benzylthiopropanoic acid. The optical isomers were prepared by resolution with brucine and quinine. Removal of benzyl groups yielded (+)- and (–)-2-hydroxy-3-mercaptopropanoic acid. Desulphurization with Raney nickel gave (+)- and (–)-lactic acid. Configuration and optical purity of all isomers have been determined.
16 citations
TL;DR: Highly impure residues obtained from an extract of alkalinized tissues can be purified by dissolving the residue in 5 ml of sulphuric acid and heating the solution on water bath with 0.1 g ninhydrin and 1.5 ml pyridine for one hour.
Abstract: Highly impure residues obtained from an extract of alkalinized tissues can be purified by dissolving the residue in 5 ml of sulphuric acid (pH 5) and heating the solution on water bath with 0.1 g ninhydrin and 1.5 ml pyridine for one hour. The reaction products are acidified (pH 1–2) with sulphuric acid and washed with ethyl acetate (2×30 ml). The washed aqueous phase is alkalinized and extracted with chloroformbutanol (9:1) (1×40 ml). The chloroform layer is washed with water (2×2 ml), filtered and evaporated to give a residue suitable for chromatographic analysis. This purification procedure was applied to aliquots of an extract of putrefied tissues to which known amounts of atropine, brucine, caffeine, strychnine, heroin, hyoscine, morphine and quinine were added. Good recoveries were obtained (71–100%) when the added amount was over 1 mg. Fair recoveries were obtained with amounts in the range of 1 to 0.1 mg, except for atropine, hyoscine and quinine which gave low recoveries (15–30%). For general application, the ninhydrin purification procedure must follow a previous ether extraction in basic medium to save the sympathicomimetic amines and some labile alkaloids.