Department of Chemistry, Faculty of Science, Chulalongkorn University , Phayathai Road, Patumwan Bangkok 10330, Thailand.
Department of Environmental Science, SaiGon University , Ho Chi Minh City 748355, Vietnam.
J Nat Prod. 2017 Feb 24;80(2):261-268. doi: 10.1021/acs.jnatprod.6b00465. Epub 2017 Feb 9.
The chemical investigation of the EtOAc extract of Lobaria orientalis collected in the southwestern part of Central Vietnam led to the isolation of new β-orcinol depsidones, lobarientalones A and B (1 and 2), and diphenyl ethers, lobariethers A-E (3-7). These types of structures are often reported in different lichen species, but the absolute configuration of the stereogenic acetal center has not been defined. This is the first assessment of the (1S) absolute configuration of the stereogenic acetal center using electronic circular dichroism (ECD) spectroscopic data and by comparison with the ECD data of analogous compounds. Based on the co-occurrence of the depsidones, 1,10-di-O-methylstictic acid (8) and (1-2), and diphenyl ethers (3-7), a plausible biosynthesis route toward 1-8 is proposed.
越南北部西南部采集的东方石耳的 EtOAc 提取物的化学研究导致了新的β-愈创木酚酸去甲替林的分离，即 lobarientalones A 和 B（1 和 2）以及二苯醚 lobariethers A-E（3-7）。这些类型的结构经常在不同的地衣物种中报道，但立体乙缩醛中心的绝对构型尚未确定。这是首次使用电子圆二色性（ECD）光谱数据并通过与类似化合物的 ECD 数据进行比较来评估立体乙缩醛中心的（1S）绝对构型。基于去甲替林、1,10-二-O-甲基石耳酸（8）和（1-2）以及二苯醚（3-7）的共存，提出了一个可能的生物合成途径到 1-8。
