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亚美胺A和B的结构和合成,来自南非斯特罗马托利特的循环八度

George F Neuhaus¹, Xinhui Yu¹, Wakana Osaka²

¹Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon 97331, United States.

Journal of natural products

|March 17, 2025

概括

在南非的树突中发现了新的循环八二,氨基二甲和乙,在南非的树突中发现. 这些天然产品对癌细胞具有较弱的细胞毒性潜力,由于氧化应激诱导,阿马提胺B更强效.

科学领域:

海洋天然产品化学化学
生物勘探是指生物勘探.
斯特罗马托利特微生物学

背景情况:

活生生的酸 stromatolites 代表未经探索的微生物生态系统.
这些独特的地质构造可以容纳新的生物活性化合物.

研究的目的:

从南非 stromatolites 来分离和表征新的循环八二.
阐明结构并确定新型化合物的绝对配置.
评估与人类癌症细胞系对隔离化合物的细胞毒性潜力.

主要方法:

斯特罗马托利特提取物的代谢分析.
使用核磁共振 (NMR) 和液体染色学-质谱法 (LCMS^2) 阐明结构.
总固相合成用于绝对结构确认.
在体外细胞毒性测定针对质母细胞瘤,结肠和神经母细胞瘤细胞系.

主要成果:

发现和分离了两种新的循环性八二,即A (1) 和B (2) 氨基胺.
结构分析显示了常见的氨基酸和2-基-3-甲基酸残留物,脂肪酸链中存在变异 (2-基酸在1,2-基酸在2).
绝对配置通过马菲试剂确定,并通过总合成确认.
观察到较弱的细胞类型特异性细胞毒性活性,其中阿玛提胺 B 显示出比阿玛提胺 A 的效力更大,这归因于氧化应激诱导.

结论:

氨基胺A和B是从活体树突体中分离出来的新型循环八二.
总合成证实了这些化合物的绝对结构.
氨基胺在癌细胞上表现出有限的细胞毒性作用,突出了进一步研究其生物活动和作用机制的潜力.

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