Two new dimeric naphthoquinones with neuraminidase inhibitory activity fromLithospermum erythrorhizon

Abstract

The crude methanol extract of roots of Lithospermum erythrorhizon was subjected to successive chromatographic fractionation which afforded two new dimeric naphthoquinone derivatives shikometabolin E (2) and shikometabolin F (3) as well as one known compound shikometabolin A (1). The structures of compounds 1-3 were elucidated by using UV, MS, 1D and 2D NMR spectroscopic analysis. The two new dimeric naphthoquinone derivatives showed significant neuraminidase inhibitory activities.

Naphthoquinones from Onosma paniculatum with Potential Anti-inflammatory Activity

“…The 1 H and 13 C NMR spectra of 1 were quite similar to the dimeric naphthoquinone shikometabolin F [9], except from the presence of an additional pair of double bonds in 1 and the absence of one methylene and one methenyl in shikometabolin F. The additional pair of double bonds was assigned to be between C-18′ and C-19′, which was confirmed by HMBC correlations from H-18′ (δ 5.84) to C-20′ (δ 20.0), C-21′ (δ 27.0), C-17′ (δ 165.0), and C-19′ (δ 158.5) and from H-21′ (δ 1.92) to C-20′ (δ 20.0), C-19′ (δ 158.5), and C-18′ (δ 115.3) (▶ Fig. 2).…”

Shikonins as natural products from traditional Chinese medicinal plants: their biosynthesis, genetic regulation, structuralmodifications, and pharmaceutical functions

“…[3] arnebiabinone (75) [12] shikometabolin A (76) [10] shikometabolin E (77) [10] shikometabolin F (78) [10] 6-(11'-deoxyalkannin)-alkannin/shikonin β-hydroxyisovalerylate (79) [3] [13] 最早报道了紫草愈伤细胞的诱导及其培养条件，Yazaki 等 [14] 开发出使用农杆菌ATCC15834侵染紫草植株获得毛状根的方法。离体繁殖 材料能否成功生产紫草素取决于为紫草素量身定制的培养基的开发，Fujita等 [15] 成功开发出可使紫草愈伤细胞和毛状根生产紫草素的M9培养基，与紫草愈伤细 胞和毛状根的生长培养基(如LS、MS等培养基)相比，M9培养基含有较低浓度 的NH 4+ ，而Cu 2+ 的浓度高达10倍以上，由此建立了先使用改良LS培养基在光照 下进行愈伤细胞或毛状根的增殖培养，再转接到M9培养基中黑暗培养以诱导紫 草素产生的两步培养法。之后，朱汝幸等 [16] 也使用两步法成功诱导了滇紫草的 愈伤细胞并培养产生了高于原植株产率的紫草素。Haghbeen等 [17] 利用添加2,4-D 和激动素的LS培养基对新疆紫草种子发芽后的根外植体进行诱导，获得了大量 可产紫草素的新疆紫草愈伤细胞。在此基础上，Fu等 [18] 对车前叶蓝蓟毛状根进 行了诱导培养和培养体系的优化，发现该毛状根在1/2B5培养基中的培养生物量 是M9培养基的5倍，且同样能产生丰富的紫草素，其中乙酰紫草宁的产量更是高…”

Total Syntheses of Juglorescein and Juglocombins A and B

“…These compounds have a highly oxygenated, 6/6/5/6/6‐fused A/B/C/D/E ring system. The related naphthoquinone dimers zeylanone,, zeylanone epoxide, and two shikometabolins, are shown in Figure b. Zeylanone shows antibacterial and antifungal activity . This compound also exhibits cytotoxic activity against cancer cell lines .…”

“…This compound also exhibits cytotoxic activity against cancer cell lines . Shikometabolins E and F show significant neuraminidase inhibitory activity ,. Total synthesis of racemic zeylanone and zeylanone epoxide was achieved by our group .…”