Anticomplement cycloartane triterpene glycosides from Beesia calthaefolia (Maxim.)

Investigation of the n-BuOH extract of the whole plant of Beesia calthaefolia led to the isolation of three new cycloartane triterpenoids (1–3) and two known compounds (4, 5). Their structures were elucidated by 1D and 2D NMR, HRESIMS and optical rotation spectral data. All of the isolates were investigated for their inhibitory effects on the classical pathway of the complement system. Among them, compound 3 showed stronger inhibitory activity (IC₅₀ 148.0 μM) than the positive control (rosmarinic acid, IC₅₀ 181.8 μM), while other compounds (1, 2, 4 and 5) showed moderate activity. The chemical compound studied in this article was rosmarinic acid (PubChem CID: 5281792).     

New triterpene saponins from the seed cake of Camellia Oleifera and their cytotoxic activity

Two new oleanane-type triterpene saponins, identified as 16α-hydroxy-22-O-angeloyl-23-formyl-28,31-dihydroxymethylene-olean-12-ene-3β-O-{β-d-galactopyranosyl-(1 → 2)[β-d-xylopyranosyl-(1 → 2)-α-l-arabinopyranosyl(1 → 3)]-β-d-glucopyranosiduronic acid} (oleiferasaponin B₁, 1) and 22-O-hydrocinnamoyl-23-formyl-28-dihydroxymethylene-olean-12-ene-3β-O-{β-d-glucopyranosyl-(1 → 2)[β-d-xylopyranosyl-(1 → 2)-α-l-arabinopyranosyl(1 → 3)]-β-d-glucopyranosiduronic acid} (oleiferasaponin B₂, 2), were isolated from the seed cake of Camellia oleifera Abel. Their structures were established by extensive 1D- and 2D-NMR experiments along with TOF-MS analysis and acid hydrolysis. The cytotoxicity of the isolated compounds was evaluated in four human carcinoma cell lines: A 549, SK-OV-3, SK-MEL-2 and HCT15. Both compounds 1 and 2 exhibited significantly cytotoxic activity with IC₅₀ values of 18.5 μM (A549), 11.3 μM (SK-OV-3), 13.9 μM (SK-MEL-2) and 1.6 μM (HCT15) for 1 and IC₅₀ values of 8.4 μM (A549), 6.3 μM (SK-OV-3), 9.2 μM (SK-MEL-2) and 0.8 μM (HCT15) for 2. In addition, compound 2 showed more effective cytotoxic activity than compound 1.     

酿酒酵母合成木栓酮及其衍生物的研究现状及展望

木栓酮及其衍生物在植物中普遍存在且种类繁多,具有丰富的生理药理学活性。木栓酮衍生物是以木栓酮为骨架经细胞色素氧化酶P450(cytochromeP450,CYP450)及UDP葡萄糖醛酸转移酶(UDP-glucuronosyltransferase, UGT)修饰而来。植物中天然木栓酮及其衍生物的含量极低,传统的萃取分离和化学合成效率低、能耗高且污染环境,因此,利用酿酒酵母作为宿主菌生产木栓酮及其衍生物是一种高效且环保的策略。本文从增加前体含量、提高酶活性和产物合成的亚细胞定位等方面介绍并展望了木栓酮在酿酒酵母中高效生产的策略,并介绍了目前几种常见的木栓酮衍生物研究现状,从根据碳骨架相似性挖掘CYP450、蛋白质工程改造CYP450和合成代谢基因簇的挖掘等方面展望了木栓酮衍生物的合成途径解析的新思路。     

鸦胆子抗肿瘤活性成分的化学研究

从苦木科植物鸦胆子[Brucea javanica(L.)Merr]干躁果实的硅胶干柱柱层析所得的活性部位中经层析分离得到7个四环三萜苦木内酯成份(A,B,C,D,E,F,G),经UV,IR,~1H-NMR,~(13)C-NMR等方法鉴定分别为鸦胆苦醇(Brusatol A),双氢鸦胆苦醇(Dihydrobrusatol,B),鸦胆因B(Bruceine B,C),鸦胆因D(Bruceine D,D),鸦胆因H(Bruceine H,E),鸦胆子甙A(Bruceoside A,F)和双氢鸦胆子甙A(Yadanzioside A,G)。据报道,鸦胆苦醇和鸦胆子甙A具有较强的抗肿瘤活性。     

Bryonoside and bryoside—new triterpene glycosides from Bryonia dioica

The structures of two new triterpene glycosides from Bryonia dioica have been shown, on the basis of chemical and FDMS and ¹H and ¹³C NMR s     

A comparison of lipid components of the fresh and dead leaves and pneumatophores of the mangrove Avicennia marina

The component hydrocarbons, sterols, alcohols, monobasic, α,ω-dibasic and ω-hydroxy acids of the fresh hand decayed leaves and the pneumatophores of the mangrove Avicennia marina are reported in detail. From the quantitative comparisons which can be drawn, relative changes in the lipid classes occurring during leaf decay can be highlighted. These base-line data are important to our understanding of inputs to marine intertidal sediments. During leaf decay the only significant changes were a reduction in the total absolute concentrations of monobasic acids due largely to a decrease in concentration of the C₁₈ polyunsaturated fatty acids, and an enhancement of the concentrations of the long-chain monobasic acids, ω-hydroxy acids and α,ω-dibasic acids. This resistance to degradation shown by the cutin derived acids (α,ω-dibasic, ω-hydroxy and long-chain monobasic acids) relative to the cellular and wax derived lipids may allow these cutin components to be used as quantitative markers of A. marina in mangrove associated sediments.     

3S,24S,25-Trihydroxytirucall-7-ene from Ailanthus excelsa

A new triterpene has been isolated from the root bark of Ailanthus excelsa (Simaroubaceae) and identified as 3S,24S,25-trihydroxytirucall-7-ene.