On the Configuration of β-Amino-d-Methyl Hexanoic Acid (β-Aminohomoleucine)

The configuration of (+)-B-amino-d-methyl hexanoic acid (B -aminohomoleucine) (Ila), obtained by the application of the Arndt-Eistert synthesis on L- leucine (I) was determined. B-Phthalimidoil-d- methyl hexanoyl chloride (III) was converted via Rosenmund-Zetsche reaction into the corresponding aldehyde IV and ethylene mercaptal V. Raney nickel reduction of V gave ( + )-4-phthalimido-2-methyl- hexane (VI). Hydrolysis of VI with hydrobromic acid yielded (-) - 4-amino-2 -methyl-hexane hydrobromide (VII) . The compounds VI and VII were also obtained from 1-diazo-3-phthalimido-5-methyl hexan-2-one (VIII) by a different way, Wolff rearrangement being not applied. VIII was converted to the corresponding ketone (IX), resp. thioketal (X), which was desulphurized to VI. The compounds VI and VII, obtained by both ways, had the same signs of rotation

Synthesis of the Homologue of L-Leucine (Synthesis of-β-Amino-D-methyl-caproic Acid)

It has been shown that N-Phthalyl-derivatives of a-amino- acids can be converted into the corresponding diazoketones. We have applied this reaction to the preparation of the homologue of L-leucine by the Arndt-Eistert synthesis from the hitherto undescribed diazoketone of N-phthalyl-L-leucine (I), Methanolic solution of (I) heated with silver oxyde yielded the optically active ester of the homologous acid (Il), which, refluxed with hydriodic acid, gave the free, optically active B-amino acid (III)

The Synthesis of 14C Labelled Serotonin/2-(5\u27 -Hydroxyindolyl-3\u27)-ethylamine-[l-14C]/

By modification of published procedure s on the 2-(indolyl)-3\u27) ethylamines syntheses it\u27 was possible to obtain 2-(5\u27-benzylox yindolyl-3\u27)-acetonitrile-[1-14C) (III) in a 820/o yield, from equimolar amounts of 5-benzyloxygramine methosulphate (II) (1.1 mM) and sodium cyanide-UC (1.0 mM, 1 mC). III was reduced with lithium aluminium hydride to the corresponding amine IV, catalitically debenzylated to serotonin V and isolated as crea tinine sulphate complex VI in a 640/o yield (calc\u27d on Nat4CN), having a specific activity of 1.71 μC/mg. (0.69 mC/ mM)

On the Metabolism of β-Methionine-Methyl-C14

B-Amino-y-methyl-C14-thiobutyric acid (B-methionine-methyl -C14) fed in a single dose to rats caused a negligible activity of the carbon dioxide expired. Most of the activity was found in the urine due to the unchanged compound administered, as well as to its oxydation product B - amino- y - methyl - C14 - sulfoxibutyric acid (B-methionine sulfoxide). Choline and creatinine isolated from the body tissues and creatinine isolated from the urine showed a low activity. It is assumed therefore that under such conditions only a small fraction of B -methionine transfers its methyl group to the methyl acceptors