Bates H A, Kaushal A, Deng P N, Sciaky D
Biochemistry. 1984 Jul 3;23(14):3287-90. doi: 10.1021/bi00309a026.
Histopine, an unusual amino acid derivative of histidine isolated from crown gall tumors of sunflowers (Helianthus annus) inoculated with Agrobacterium tumefaciens strain B6, was previously assigned the gross structure N-(1-carboxyethyl) histidine (2). A diastereomeric mixture containing histopine (2a and 2b) was readily prepared by reductive alkylation of (S)-histidine (1) with pyruvic acid and sodium cyanoborohydride. The individual diastereomers were prepared by reaction of (S)-histidine with (R)- and (S)-2-bromopropionic acid. (R)-N-(1-Carboxyethyl)-(S)-histidine (2a) supports the growth of A. tumefaciens whereas (S)-N-(1-carboxyethyl)-(S)-histidine (2b) is inactive. Therefore, we assign structure 2a to histopine.
组织氨酸是从接种了根癌土壤杆菌B6菌株的向日葵（Helianthus annus）冠瘿瘤中分离出的一种不寻常的组氨酸氨基酸衍生物，其总体结构先前被确定为N-(1-羧乙基)组氨酸(2)。通过(S)-组氨酸(1)与丙酮酸和氰基硼氢化钠的还原烷基化反应，很容易制备出含有组织氨酸的非对映异构体混合物(2a和2b)。通过(S)-组氨酸与(R)-和(S)-2-溴丙酸反应制备出各个非对映异构体。(R)-N-(1-羧乙基)-(S)-组氨酸(2a)支持根癌土壤杆菌的生长，而(S)-N-(1-羧乙基)-(S)-组氨酸(2b)则无活性。因此，我们将结构2a指定为组织氨酸。
