Investigation of the secondary metabolites of Streptomyces virginiae CMB-CA091 isolated from the quartz-rich (tepui) soil of a cave in Venezuela yielded two new dimeric phenazine glycosides, tepuazines A and B (1 and 2); three new monomeric phenazine glycosides, tepuazines C–E (3–5); and a series of known analogues, baraphenazine G (6), phenazinolin D (7), izumiphenazine C (8), 4-methylaminobenzoyl-l-rhamnopyranoside (9), and 2-acetamidophenol (10). Structures were assigned to 1–10 on the basis of detailed spectroscopic analysis and biosynthetic considerations, with 1 and 2 featuring a rare 2-oxabicyclo[3.3.1]nonane-like ring C/D bridge shared with only a handful of known Streptomyces natural products. We propose a plausible convergent biosynthetic relationship linking all known members of this structure class that provides a rationale for the observed ring C/D configuration.

中文翻译：

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Tepuazines A–E：吩嗪糖苷，来自委内瑞拉富含石英 (Tepui) 洞穴土壤的弗吉尼亚链霉菌 CMB-CA091

对从委内瑞拉一个洞穴富含石英 (tepui) 的土壤中分离出来的弗吉尼亚链霉菌CMB-CA091的次生代谢物进行研究，得到了两种新的二聚吩嗪糖苷，tepuazine A 和 B（ 1和2）；三种新的单体吩嗪糖苷，tepuazines C–E ( 3 – 5 )；以及一系列已知的类似物，巴拉吩嗪 G ( 6 )、吩嗪啉 D ( 7 )、伊豆吩嗪 C ( 8 )、4-甲基氨基苯甲酰基-1-吡喃鼠李糖苷 ( 9 ) 和 2-乙酰氨基苯酚 ( 10 )。根据详细的光谱分析和生物合成考虑，将结构分配为1 – 10 ，其中1和2具有罕见的 2-氧杂双环[3.3.1]壬烷样环 C/D 桥，仅与少数已知的天然链霉菌共享产品。我们提出了一种合理的趋同生物合成关系，将这一结构类别的所有已知成员联系起来，为观察到的环 C/D 构型提供了理论依据。