As a possible formation mechanism of glycine in astrophysical environments, a reaction path via aminoacetonitrile and hydantoin (2,4-imidazolidinedione), which have been detected in an interstellar cloud and meteorites, respectively, were analyzed using the density functional theory. The formation of hydantoin from aminoacetonitrile via the Bücherer-Bergs reaction and the hydrolysis of hydantoin were investigated. The results showed that the catalytic water molecules significantly lower the reaction barriers for the formation of hydantoin. Although the highest barrier is still too high that the pathway is inactive in an interstellar medium, this reaction would proceed during the heating of the meteorite parent body.

中文翻译：

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在外太空环境中通过乙内酰脲中间体形成甘氨酸的理论研究

作为天体环境中甘氨酸的可能形成机理，使用密度泛函理论分析了分别在星际云和陨石中检测到的经由氨基乙腈和乙内酰脲（2,4-咪唑烷二酮）的反应路径。研究了通过Bücherer-Bergs反应从氨基乙腈形成乙内酰脲和乙内酰脲的水解。结果表明，催化水分子显着降低了形成乙内酰脲的反应障碍。尽管最高的障碍仍然太高，以至于该路径在星际介质中不起作用，但该反应将在陨石母体加热期间进行。