Seco-Dendrobine-Type Alkaloids and Bioactive Phenolics from Dendrobium findlayanum

Abstract

Investigation of the 95% EtOH extract of stems of Dendrobium findlayanum afforded four new seco-dendrobines, findlayines A-D (1-4); two known dendrobines, dendrobine (5) and 2-hydroxydendrobine (6); and four new phenolic compounds, dendrofindlaphenols A-C (7, 9, and 10) and 6″-de-O-methyldendrofindlaphenol A (8). Compounds 1 and 2 are the first seco-dendrobines possessing a seven-membered lactam moiety, with 3 and 4 derived from the oxidative cleavage of the C-2-C-3 bond of dendrobine. The structures were established using spectroscopic methods and by comparison with literature data. The absolute configurations of 1-4 were confirmed via single-crystal X-ray diffraction data. Cytotoxic activity assays against HL-60, SMMC-7721, A-549, MCF-7, and SW480 human cancer cell lines revealed IC values ranging from 2.3 to 5.3 μM for compound 7, from 19.4 to 34.4 μM for 8, and from 49.4 to 96.8 μg/mL for the EtOAc extract. An assay of the inhibition of NO production with RAW 264.7 cells indicated that 8 had an IC value of 21.4 μM, and the EtOAc extract, 10.5 μg/mL. The EtOAc extract possessed DPPH radical scavenging activity of 69.93% at 100 μg/mL.

Anti‐inflammatory effect of alkaloids extracted from Dendrobium aphyllum on macrophage RAW 264.7 cells through NO production and reduced IL‐1, IL‐6, TNF‐α and PGE2 expression

“…The expression of iNOS mRNA in RAW 264.7 cells treated with high concentrations of DAA did not differ from that in the normal control group. In a previous study, an assay for the inhibition of NO production using RAW 264.7 cells indicated that 6′‐de‐O‐rnethyldendrofindlaphenol A from the 95% EtOH extract of a Dendrobium findlayanum stem had an IC50 value of 21.4 μ m (Yang et al, ). Previous investigations also revealed that sesquiterpene pyridine alkaloids exhibit potent anti‐inflammatory activity and that many such alkaloids are considered important chemotaxonomic indicators (Al‐Omar et al, ).…”

Holistic approach to microwave-reflux extraction and thermo-analytical fingerprints of under-utilized Artocarpus heterophyllus seed wastes

“…This is an important spicy compound with flavouring attribute which could be a potential alternative for food preservations and as an anti-inflammatory agent when isolated as a single pure compound ( Li et al., 2019 ). Moreover, the presence of other secondary alkaloids such as Dendrocandin F (m/z = 315.13, RT = 6.72 min) ( Yang et al., 2018 ), Yakuchinone A (m/z = 357.17, RT = 12.38 min) ( Sur et al., 2019 ), Aspidinol (m/z = 269.10, RT = 6.45min) ( Wang et al., 2016 ), Saponin PA (m/z = 853.46, RT = 10.89 min) ( Xu et al., 2013 ) confirmed the activities of A. heterophyllus as anti-tumour agents which makes them potential drug candidates against cancerous cells.…”

Bibenzyl Derivatives from Dendrobium nobile

“…普通 HMBC 谱中未发 现两个联苄单元之间有相关信号 [8,9] . 通过查找文献发 现两个联苄单元有可能通过联苯方式 [10,11] 或者是 1,4-二 氧 六 环 方式连 接 [12,13] . 通过 联 苯 方式连 接 的 化合物 dendronophenol A [10] 和化合物 1 的核磁数据基本一致, 很有可能文献结构解析有错误, 因为假如是联苯形式连 接, 连接 2 个苯环的碳原子会因为旁边羟基和甲氧基的 屏蔽作用向高场移动, 其化学位移值将远小于 130 [14,15] , 其碳谱数据的模拟值分别为 δ 108.6 和 110.3 跟实际测得 值 δ 131.7 和 132.5 相差太大, 而且联苯形式往往会有阻 转异构现象存在 [16] .…”