@article{oai:niigata-u.repo.nii.ac.jp:00002570,
 author = {今泉, 洋 and 長澤, 智史 and 狩野, 直樹},
 issue = {12},
 journal = {Radioisotopes, Radioisotopes},
 month = {Dec},
 note = {生態系に及ぼすトリチウム(^3H又はT)の影響とHを含む物質の反応性を明らかにするため,同一分子内に異なる3種の官能基を持つL-システイン酸とL-システインの反応性を追究した。これらの物質とHTO蒸気との間の水素同位体交換反応(T-for-H交換反応)を50～70℃の温度範囲で観測し,得られたデータとA〝-McKayプロット法とを用いて各々の反応を解析した結果,次のことが明らかになった。(1)異なる3種の官能基を持つこれらの化合物中の各官能基の反応性は温度の上昇に伴い増加する。(2)L-システイン酸中のSO_3H基の反応性は,COOH基の反応性のおよそ2.6倍であり,NH_2基の反応性のおよそ5.8倍である。(3)L-システイン中のSH基の反応性は,COOH基の反応性のおよそ1.4倍であり,NH_2基の反応性のおよそ3.5倍である。(4)NH_2基は電子求引性の大きい置換基が置換すると反応が促進されるが,COOH基ではあまり影響がない。(5)異なる3種の官能基を持つ脂肪族化合物について,A〝-McKayプロット法を使うと,その物質の反応性を,マスク剤等を使わないで非破壊的・同時分析的に明らかにできる。(6)ある種の物質へのT取込みの程度を,非破壊的・定量的に明らかにできる。(7)本研究で得られた結果は,環境中のT汚染防止のために役立ち,また今後,複数の官能基を持つある種の物質の反応性を追究するための解析手法として役立つ。, In order to clarify both the effect of tritium (^3H or T) on the ecosystem and the reactivity of materials having H atoms, the reactivity of L-cysteic acid (or L-cysteine) having three different kinds of functional groups was studied. The hydrogen-isotope exchange reaction between each compound and HTO vapor (T-for-H exchange reaction) was observed at 50-70℃, and the reaction was analyzed with both the A"-McKay plot method and the data obtained from the exchange reaction. The following seven matters have been consequently found in the T-for-H exchange reaction. (1) The reactivity of the functional groups in each compound increases with increasing temperature. (2) As to L-cysteic acid, the reactivity of SO_3H group is 2.6 times greater than that of COOH one, and is 5.6 times greater than that of NH_2 one. (3) As to L-cysteine, the reactivity of SH group is 1.4 times greater than that of COOH one, and 3.5 times greater than that of NH_2 one, (4) The reactivity of NH_2 group progressed by the substituent having large electron-attractive effect, however, the reactivity of COOH group does not so progress by such a substituent. (5) Applying the A"-McKay plot method, the reactivity of the three functional groups in each aliphatic compound can be nondestructively and simultaneously clarified under the condition of non-masking reagent. (6) Degree of T-incorporation in a certain material can be nondestructively and quantitatively clarified. (7) The results obtained in this work is useful to prevent T contamination in the environment and to clarify the reactivity of the materials having plural functional groups, and the method used in this work can be also useful as a analytical method to obtain the reactivity of multi-functional groups in a certain compound.},
 pages = {709--718},
 title = {異なる3種の官能基を持つL-システイン酸とL-システインの反応性の同時解析},
 volume = {55},
 year = {2006}
}