Tritio compounds

Another amino acid hydroxylase, tryptophan-5-hydroxylase, catalyzes the conversion of 5-tritiotryptophan to 4-tritio-5-hydroxytryptophan (Figure 2) (24). With this substrate, exchange experiments have shown that only the 4-tritio isomer is formed rather than a mixture of the 4- and 6-tritio compounds. 

Tritio compounds. A mixture of the startg. sec. amine with a little KI added to 0.5 mole y-chlorO 4-fluoro-2-tritiobutyrophenone, after 15 min. at room temp, heated slowly until the hydrochloride of the sec. amine crystallizes, after seeding if necessary, then the temp, raised to 130-150° during 15 min. and kept there for 5 min. -> bromoperidol. Y 75-85%. F. e. s. W. Soudijn and I. van Wijngaarden, J, Labelled Compounds 4, 159 (1968). 

Tritio compounds. 4-Pyridoxic acid lactone refluxed 4 hrs. with tritiated LiAlH4 in tetrahydrofuran, then water added and acidified with acetic acid -> pyrid-... 

Tritio compounds s. Compounds, H-labeled, Ditritio compds. Triton B 26,270 27, 456, 917 ... 

Trideuteriomethyl compounds. Na-5-bromothiophene-2-carboxylate refluxed ca. 3 hrs. on a water bath with Raney-Ni alloy in 99.5% deuterium oxide in the presence of Na-methoxide 2,2,3,4,5j5,5-heptadeuteriovaleric acid. Y 70-80%.— Tritio compounds can be obtained similarly by using tritium oxide in place of deuterium oxide. F. e. s. V. Bac, P. Buu-Hoi, and D. Xuong, Bl. 1962, 1077. 

Tritio-denitration In the presence of azoisobutyronitrile as radical initiator, tri-n-butyltin tritide can tritio-denitrate secondary and tertiary nitro compounds to give the respective labeled derivatives. Primary nitro groups can only be denitrated if they are located adjacent to keto groups . The carbanion-stabilizing properties of nitro groups facilitate the introduction of electrophiles such as alkyl halides, aldehydes and ketones at the a-position. Furthermore, nitroolefins are excellent Michael acceptors as well as dienophiles, which enables the regioselective and chemoselective synthesis of a broad range of acyclic and... 

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