Methods are described for the preparation of derivatives of the polyamines 1,4-diaminobutane (putrescine) and N-(3-aminopropyl)-1,4-diaminobutane (spermidine) in which a particular amino group is modified with, e.g., a guanidino function. Specific amino groups in these polyamines were protected as N-trifluoroacetyl and N-4-azidobenzyloxycarbonyl derivatives, which were unmasked chemoselectively using methanolic ammonia and dithiothreitol–triethylamine, respectively. Guanidino functions were introduced by an improved procedure in which an amino group was treated with 3,5-dimethyl-N-nitro-1H-pyrazole-1-carboximidamide in methanol to give a nitroguanidine derivative, from which the nitro group was removed by catalytic transfer hydrogenation. The methodology is exemplified by the development of efficient preparative routes to agmatine and hirudonine. The integrity of the sequence of protection/deprotection leading to hirudonine was confirmed by a crystal-structure analysis of its sulfate. The effect of selected compounds on the uptake of putrescine into rat lung cells was determined and showed that N
4-(4-azidobenzyloxycarbonyl)spermidine was the best inhibitor (Ki = 3.4 µM).
本文描述了制备
多胺衍
生物1,4-二
氨基
丁烷(
腐胺)和N-(3-
氨基丙基)-1,4-二
氨基
丁烷(
精胺)的方法,其中特定的
氨基被修饰为
胍基等官能团。在这些
多胺中,特定的
氨基被保护成N-三
氟乙酰基和N-4-
叠氮苄氧羰基衍
生物,并分别使用
甲醇氨和二
硫苏糖醇-
三乙胺选择性地脱去保护。通过改进的方法引入
胍基官能团,其中
氨基与3,5-二甲基-N-硝基-1H-
吡唑-1-羧
酰亚胺在
甲醇中反应生成
硝基胍衍
生物,然后通过催化转移氢化除去硝基。该方法以开发高效的制备路线至
胍氨酸和蛭素为例。保护/去保护序列的完整性通过其
硫酸盐的晶体结构分析得到了证实。评估了选定化合物对大鼠肺细胞摄取
腐胺的影响,并显示N-4-(4-
叠氮苄氧羰基)
精胺是最好的
抑制剂(Ki = 3.4 µM)。