A novel cyclic amino acid was detected in and subsequently isolated from extremely halophilic species of the bacterial genus Ectothiorhodospira. The structure of this new compound was elucidated by a combination of nuclear magnetic resonance (NMR) techniques and mass spectrometry. 1,4,5,6-Tetrahydro-2-methyl-4-pyrimidinecarboxylic acid is only accumulated within the cytoplasm under certain growth conditions and seems to serve an osmoregulatory function. There is no previous reference to this molecule in the chemical literature and we, therefore, propose to use the trivial name 'ectoine', due to its discovery in members of the bacterial genus Ectothiorhodospira. (formula: see text).

中文翻译：

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1,4,5,6-四氢-2-甲基-4-嘧啶羧酸。一种新的环状氨基酸，来自嗜盐硫菌属嗜盐菌的嗜盐营养细菌。

在细菌嗜盐球菌螺旋藻的极嗜盐菌种中检测到一种新的环状氨基酸，并随后从中分离出了这种环状氨基酸。通过核磁共振（NMR）技术和质谱的结合阐明了这种新化合物的结构。1,4,5,6-四氢-2-甲基-4-嘧啶羧酸仅在某些生长条件下积累在细胞质中，似乎起到了渗透调节功能。化学文献中以前没有提及此分子，因此，由于其在细菌埃克托硫菌属的成员中发现，我们建议使用平凡的名称“ ectoine”。（公式：参见文字）。