离线二维液相色谱-串联质谱法检测姜黄中姜黄素类和倍半萜类化合物

采用二维高效液相色谱-电喷雾质谱法,以新型色谱填料ClickCD为第一维分离材料,WatersXTerraMSC18柱作为第二维,以乙腈和0.2%甲酸-水为梯度洗脱流动相,对姜黄中的姜黄素类和倍半萜类化合物进行分离鉴定.结果表明,基于不同分离机理的ClickCD和C18二维色谱系统具有分离度高、正交性好的优点,使待测化合物得到了有效分离.特别是与高灵敏度的质谱联用,可以大大提高化合物的鉴定能力.通过与对照品的色谱保留时间和质谱数据对比,并结合文献报道,共鉴定了20个姜黄素类化合物和19个倍半萜类化合物,其中27个为对照品的同分异构体.为中药化合物的表征和活性化合物的制备提供了有效方法.     

Synthesis of bisabolane sesquiterpenes: a Johnson-Claisen rearrangement approach

<正>Several bisabolane sesquiterpenes,(±)-curcumene,(±)-curcuphenol,(±)-curcudiol and(±)-curcuhydroquinone,have been synthesized in racemic form and fully characterized.The salient characteristic of our approach is that a Johnson-Claisen arrangement was involved as a key step.     

Insecticidal,cytotoxic and anti-phytopathogenic fungal activities of chemical constituents from the aerial parts of Ferula sinkiangensis

Abstract

A new rare monoterpene coumarin (1) and its two known analogues (2–3), together with two sesquiterpenes (6–7) and ferulic acid (8) were isolated from the aerial parts of Ferula sinkiangensis. The structure of new compound was established on the basis of 1D and 2D NMR data and HRESIMS data interpretation. Insecticidal, cytotoxic and anti-phytopathogenic fungal activities of isolated compounds were evaluated against third-instar larvae of Spodoptera exigua and its cell line, and three plant pathogenic fungi respectively. Compounds 1–3 and 6–7 were found to be more effective contact toxicity to S. exigua with the corrected mortality values of 38.89%-58.89% at 10?μg/larva doses for 24?h. Further studies showed that compounds 3 and 6 exhibited cell growth inhibitory activity against S. exigua cell line with the EC₅₀ values of 22.78 and 14.64?µM for 72?h. In addition, compound 6 exhibited potent antifungal activity with MICs?=?16–32?µg/mL.     

Sesquiterpenes from Chrysoma Pauciflosculosa

Abstract

The aerial parts of Chrysoma pauciflosculosa (syn. Solidago pauciflosculosa) gave two new sesquiterpenes, (+)-β-turmerone and a bisabolane endoperoxide, together with the known (-)-α-trans-bergamotene and (+)-β-sesquiphellandrene. When exposed to air and light, (+)-β-turmerone and (+)-β-sesquiphellandrene gave oxidative degradation products, involving hydroperoxide intermediates. Photosensitized singlet oxygen reactions of (+)-β-turmerone provided a series of bisabolane-type endoperoxides. The structures of the natural compounds as well as those of the degradation products and derivatives were elucidated by chemical and spectroscopic methods, mainly NMR and MS. Aqueous solutions of (+)-β-turmerone,(+)-β-sesquiphellandrene and (-)-α-trans-bergamotene were tested for their effects on the germination and radicle growth of three Florida sandhill species, Rudbeckia hirta, Schizachyrium scoparium, Leptochloa dubia, as well as Lactuca sativa. (+)-β-Turmerone significantly inhibited germination of L. sativa, stimulated radicle growth of L. sativa and S. scoparium at the 10^?4 M level, and mildly inhibited radicle growth of R. hirta, as did (+)-β-sesquiphellandrene. (-)-α-trans-Bergamotene stimulated germination of S. scoparium and L. sativa and significantly enhanced radicle growth of S. scoparium.     

Isolation,structural elucidation and in vitro antioxidant activity of compounds from chloroform extract of Cedrus deodara (Roxb.) Loud.

This study was designed to isolate, characterise and explore in vitro antioxidant potential of compounds from the chloroform extract of Cedrus deodara wood belonging to Pinacae family. We have investigated the in vitro free radical scavenging activity of isolated compounds by measuring total antioxidant capacity (TAC) and reducing power ability. From the chloroform extract five sesquiterpenes namely atlantone, himaphenolone, atlantolone, deodardione and atlantone-2,3-diol were identified. Himaphenolone and deodardione from the chloroform extract of this plant have been isolated for the first time. A marked dose-dependent reducing power and strong TAC were found in favour of himaphenolone and atlantone-2,3-diol, respectively. Moreover, deodardione and atlantolone also exhibit good antioxidant potentials. However, atlantone has showed least antioxidant activity. In conclusion, the chloroform extract of C. deodara exhibited significant antioxidant potential mainly due to the presence of sesquiterpenes which may be responsible for various pharmacological activities of this plant.     

Structure and cytotoxic evaluation of five 12-oxygenated eremophilanes from Ligularia lingiana

Five new 12-oxygenated eremophilane sesquiterpenoids bearing a B-ring enone system were isolated from Ligularia lingiana S.W. Liu (Asteraceae) collected in China. Compound 5 was a Diels–Alder adduct of 3α-angeloyloxy-7βH-8-oxoeremophila-9,11(13)-dien-12-al and the monoterpene, ocimene. Compound 1 showed cytotoxic activities against HeLa, HL60, Jurkat, and NIH-3T3 cells at IC₅₀ 0.0407, 0.440, 0.313, and 3.48 μM, respectively.     

New cytotoxic halogenated sesquiterpenes from the Egyptian sea hare, Aplysia oculifera

Two new sesquiterpenes, oculiferane (1) and epi-obtusane (2) have been isolated and identified from an acetone extract of the digestive gland of the sea hare, Aplysia oculifera. The structures were elucidated by spectroscopic analysis including HREIMS, ¹H, ¹³C, DEPT, ¹H–¹H COSY, HMQC, and HMBC NMR; the relative configuration was confirmed by X-ray analysis. Compounds 1 and 2 exhibited cytotoxic activity in vitro against several human cancer cell lines with IC₅₀ values in the low μg/ml range.     

Total syntheses of the sesquiterpenes β-corymbolol and corymbolone

The first total synthesis of racemic corymbolone, an eudesmane sesquiterpene isolated from Cyperus species used in traditional medicine to treat many diseases, is reported. In the developed sequence, the immediate precursor of corymbolone is the diol β-corymbolol, an epimer at C₁ of the natural α-corymbolol. Thus, starting from the readily available Wieland-Miescher Ketone, the title compounds were achieved in 11 and 12 steps, respectively, in ca. 3% overall yield.     

Aristolane Sesquiterpenes and Highly Brominated Indoles from the Marine Red Alga Laurencia similis (Rhodomelaceae)

Three new polybrominated 1H‐indoles, compounds 1 – 3 , and three new aristolane sesquiterpenes, compounds 4 – 6 , were isolated from the marine red alga Laurencia similis, together with seven known natural products. Their structures were elucidated on the basis of detailed spectroscopic and mass‐spectrometric analyses, as well as by comparison with literature data.     

Ligustolide A and B, two novel sesquiterpenes with rare skeletons and three 1,10-seco-guaianolide derivatives from Achillea ligustica

Achillea ligustica afforded two novel sesquiterpene lactones with rare 5/6/5 skeletons, three 1,10-seco-guaianolides and a chlorine-containing sesquiterpene lactone as well as six known compounds, including two monoterpenes, two guaianolides, one eudesmane and one secocaryophyllene derivative. The structures of the compounds were elucidated by extensive application of one- and two-dimensional NMR spectroscopy.