太平洋侧花海葵中四个新神经酰胺的鉴定太平洋侧花海葵中四个新神经酰胺的鉴定

目的研究太平洋侧花海葵(Anthopleura pacifica)中的生物活性成分。方法采用稻瘟霉模型生物活性追踪方法,应用色谱技术进行分离,根据理化性质和波谱分析鉴定结构。结果得到了1个对稻瘟霉显示活性的组分,并鉴定为4个神经酰胺的混合物:N-羟乙基-N-十四酰-(2S,3R)-十八碳鞘氨醇-4(E),8(E)-二烯(a),N-羟乙基-N-(9Z-十六烯酰)-(2S,3R)-十八碳鞘氨醇-4(E),8(E)-二烯(b),N-羟乙基-N-十六酰-(2S,3R)-十八碳鞘氨醇-4(E),8(E)-二烯(c)和N-羟乙基-N-(13Z-二十二烯酰)-(2S,3R)-十八碳鞘氨醇-4(E),8(E)-二烯(d)。结论化合物a～d均为新的神经鞘氨醇化合物。     

太平洋侧花海葵中的化学成分(Ⅲ)

目的　研究太平洋侧花海葵的活性成分。方法　采用稻瘟霉模型生物活性追踪方法 ,应用多种色谱技术进行分离 ,理化性质和波谱数据鉴定其结构。结果　分离并鉴定了 9个化合物 :正十六烷 ( ) ,正十三醇 ( ) ,棕榈酸 ( ) ,硬脂酸 ( ) ,棕榈酸甲酯 ( ) ,花生酸甲酯 ( ) ,1 - O-蜡酰甘油酯 ( )以及 2 S,3 R,Δ4 (E) ,Δ8(E) -十八碳鞘氨醇 -正十六碳酰胺和其同系物 2 S,3 R,Δ4 (E) ,Δ8(E) -十八碳鞘氨醇 -正十四碳酰胺的混合物 ( 和 ) ,其中 和 的混合物对稻瘟霉的最小菌丝变形浓度为 6 3 mg· L-1。结论　 9个化合物均为首次从该种海葵中获得 ,( 和 )具有诱导稻瘟霉菌丝变形活性     

太平洋侧花海葵中的化学成分(Ⅱ)

目的:研究太平洋侧花海葵的活性成分。方法:采用稻瘟霉模型生物活性追踪方法,应用多种色谱技术进行分离,理化性质和波谱数据鉴定其结构。结果:分离并鉴定了 5个化合物,5α,8α-过氧麦角甾-6,22-二烯-3β-醇(Ⅰ),对羟基苯甲醛(Ⅱ),N-甲基吡啶-2-羧酸盐(Ⅲ),脲基甲酸乙酯(Ⅳ),牛磺酸(Ⅴ),其中化合物和对稻瘟霉的最小菌丝变形浓度分别为0.46mmol·L~(-1)和1.9mmol·L~(-1)。结论:5个化合物均为首次从该种海葵中获得,化合物和具有诱导稻瘟霉菌丝变形活性。     

海洋微生物中具有引起稻瘟霉孢子形态变异活性的菌株筛选

目的从海洋微生物的次级代谢产物中发现新的具有抗肿瘤活性的新化合物以用于新的抗肿瘤药物的研制开发。方法以稻瘟霉孢子形态变异为指标的生物活性物质筛选模型 ,对 2 0 0株海洋微生物资源菌株进行了反复筛选。结果得到了 6株在其发酵液中能够产生较强生物活性物质的菌株 ,即海豚葡萄球菌 (Staphylococusdelphini)、拟青霉 (Paecilomycessp )、土曲霉 (Aspergillusterreus)、青霉 (Penicilliumsp .)、中华拟青霉 (Sinopaecilomyces)、海洋芽孢杆菌 (Bacillusmarinus) ;并且对这 6株菌株的生长发育稳定性 ,遗传稳定性和生物活性物质的热稳定性进行了考察 ,发现其中的 4株菌株 ,即拟青霉 (Paecilomycessp )、青霉 (Penicilliumsp )、中华拟青霉 (Sinopae cilomyces)、海洋芽孢杆菌 (Bacillusmarinus)的各项稳定性良好。 结论为具有抗肿瘤活性物质的追踪分离奠定了基础     

抗稻瘟霉活性化合物A73的结构鉴定

以稻瘟霉分生孢子生长形态异常或抑制为指标，从土壤真菌中筛选新抗真菌、抗肿瘤活性物质的过程中，得到活性菌株１３１〔１〕．通过对其次级代谢产物进行活性跟踪分离，得到活性化合物３，４二氢９，１０二羟基７甲氧基３甲基１Ｈ萘并〔２，３ｃ〕吡...     

中药墨旱莲中的三萜皂苷

目的　研究中药墨旱莲Ecliptaprostrata L.中的三萜皂苷化合物。方法　应用柱色谱和HPLC法分离纯化,通过光谱分析(IR ,MS ,¹HNMR ,¹³CNMR ,DEPT ,HMQC和HMBC)鉴定其化学结构。结果　分离并鉴定了5个三萜皂苷,其中2个新化合物eclalbasaponinsXI(4)和XII(5 )的结构分别为:3-O-[β-D-吡喃葡糖(1→2 )-β-D-吡喃葡糖]-16α-乙氧基 齐墩果酸-28-O-β-D-吡喃葡糖苷(4)和3-O-[(2O-硫酰基-β-D-吡喃葡糖) (1→2 )-β-D-吡喃葡糖] 刺囊酸-28-O-β-D-吡喃葡糖苷(5 )。结论　4和5为新化合物,1和5具有诱导稻瘟霉菌丝变形活性。     

神经酰胺在胰岛β细胞凋亡中作用的研究进展

胰岛β细胞凋亡是糖尿病发生及进展的重要机制,研究表明神经酰胺在β细胞凋亡中发挥了重要作用。它通过激活内质网应激、内/外源性细胞凋亡途径、改变线粒体膜通透性诱导β细胞凋亡,同时介导ROS/RNS、炎症因子等细胞毒作用,使胰岛β细胞进一步丢失、胰岛素分泌减少。本文就神经酰胺在胰岛β细胞凋亡过程所发挥的作用作一综述。     

土壤丝状真菌AF-5、SQ_2-17菌株的筛选及其抗菌活性的研究

从辽宁、山东等省采得的 45份土样进行了菌种分离及纯化 ,共获得 482株丝状真菌 ,利用以稻瘟霉分生孢子形态异常作为生物活性筛选模型 ,对其进行了初筛 ,初步得到 2 42株活性菌株 ,经多次复筛获得了既对稻瘟霉菌株有较强活性又能抑制一些病原真菌生长的 16株活性菌株。其中AF 5、SQ2 17菌株能使稻瘟霉孢子高度变形 ,同时又具有较强的抗病原真菌作用及良好的遗传稳定性。     

海星中具有生物活性总皂苷的分离纯化

目的利用稻瘟霉生物活性成分跟踪筛选模型,对海星中皂苷进行提取和分离纯化。方法用65%EtOH对粉碎的海星(干)进行回流提取,减压浓缩后均匀分散于水中,用石油醚和正丁醇进行萃取,浓缩正丁醇得海星总皂苷,对其进行稻瘟霉生物活性测试。海星总皂苷粗提物通过正相硅胶、反相硅胶及葡聚糖凝胶LH-20柱层析进行分离纯化。用薄层层析法(TLC)检测把相同的洗脱液收集在一起,得到所需要的有效部位。结果与结论通过稻瘟霉生物活性筛选知海星乙醇粗提物、海星总皂苷均具有抗有丝分裂活性,而石油醚粗提物没有显著的活性。海星总皂苷通过正相硅胶和反相硅胶柱层析分离得到D1～D66个含有海星皂苷的组分,其中D1、D3、D4、D5、D6在TLC上呈现出单一斑点。D2进一步通过葡聚糖凝胶LH-20柱层析进行分离,得到收率约为81.2%的组分a,收率约为3%的组份b。     

中药土贝母中环形双糖链皂苷活性成分的分离和鉴定

目的:研究中药土贝母中的环形双糖链皂苷活性成分。方法:采用稻瘟霉模型生物活性追踪方法,应用多种色谱技术进行分离,根据波谱解析和化学手段鉴定其结构。结果:分离并鉴定了4个具有诱导稻瘟霉菌丝变形活性的环形双糖链皂苷:tubeimosideⅠ(1),tubeimosideⅡ(2),tubeimosideⅢ(3)和tubeimosideⅤ(4)。结论:化合物(4)为一种新的环形双糖链皂苷,是第4个从天然界获得的该类型皂苷,且对K-562和BEL-7402肿瘤细胞显示显著的细胞毒性,对1%兔红细胞悬液有较强溶血作用。     

Three new sulfated triterpenoids from the roots of Gypsophila pacifica

Three new sulfated triterpenoids (1–3), along with one known compound (4), were isolated from the roots of Gypsophila pacifica Kom. The structures of the new compounds were established as 3β-O-sulfate gypsogenin 28-O-β-d-glucopyranosyl ester (1), 3β-O-sulfate gypsogenin (2), and 3β-O-sulfate quillaic acid (3) on the basis of 1D, 2D NMR, and HR-ESI-MS methods.     

Three new sulfated triterpenoids from the roots of Gypsophila pacifica

Three new sulfated triterpenoids (1-3), along with one known compound (4), were isolated from the roots of Gypsophila pacifica Kom. The structures of the new compounds were established as 3β-O-sulfate gypsogenin 28-O-β-d-glucopyranosyl ester (1), 3β-O-sulfate gypsogenin (2), and 3β-O-sulfate quillaic acid (3) on the basis of 1D, 2D NMR, and HR-ESI-MS methods.     

New tetracyclic diterpenoid and new ceramides from the soft coral Sinularia conferta

The new tetracyclic diterpenoid confertdiate (1) and two new ceramides, (2) and (3), have been isolated from the soft coral Sinularia conferta, collected from Sanya Bay, Hainan Island, China. Their structures have been elucidated by spectroscopic analysis, and comparison of the ¹³C NMR data with those of the known diterpenoid isomandapamate confirmed the structure of 1.     

New ceramides from the sponge Cinachyra cavernosa

Two new ceramides 1 and 2, and tetillapyrone 3 have been isolated from the Indian sponge Cinachyra cavernosa. The structures of 1, 2, and 3 were determined by spectroscopic and chemical analyses.     

Metabolism of aminoglutethimide in humans. Identification of four new urinary metabolites

Four new metabolites of aminoglutethimide have been identified in the urine of patients being treated chronically with the drug. These were products of hydroxylation of the 3-ethylpiperidine-2,6-dione residue, namely 3-(4-aminophenyl)-3-ethyl-5-hydroxypiperidine-2,6-dione and its acetylamino analog, 3-(4-aminophenyl)-3-(1-hydroxyethyl)piperidine-2,6-dione, and 3-(4-aminophenyl)-3-(2-carboxamidoethyl)tetrahydrofuran-2-one, the lactone formed by rearrangement of 3-(4-aminophenyl)-3-(2-hydroxyethyl)piperidine-2,6-dione. The metabolites were isolated by reverse-phase thin layer chromatography and characterized by comparison of their mass spectra either with those of synthetic samples or with the mass spectra of analogous metabolites previously identified in the urine of rats. These new metabolites were minor constituents compared with aminoglutethimide and with the previously identified major metabolites 3-(4-acetylaminophenyl)-3-ethylpiperidine-2,6-dione and 3-(4-hydroxylaminophenyl)-3-ethylpiperidine-2,6-dione. There were marked species differences between rat and human inasmuch as almost all the metabolites in the urine of the rat were N-acetylated whereas most of the human metabolites were not. However, 5-hydroxylation of the piperidinedione residue was stereoselective in the same sense in both species, the cis isomer being formed exclusively. Synthetic cis-3-(4-aminophenyl)-3-ethyl-5-hydroxypiperidine-2,6-dione did not inhibit the activity of the target enzyme systems desmolase and aromatase in vitro, and therefore, like other metabolites so far described, is an inactivation product of the drug.     

New ceramides from the sponge Cinachyra cavernosa

Two new ceramides 1 and 2, and tetillapyrone 3 have been isolated from the Indian sponge Cinachyra cavernosa. The structures of 1, 2, and 3 were determined by spectroscopic and chemical analyses.     

Amino acid sequence of two sea anemone toxins from Anthopleura fuscoviridis

The amino acid sequences of two toxins, AFT-I and AFT-II, from the sea anemone Anthopleura fuscoviridis were determined. AFT-I and -II consist of 47 and 48 amino acid residues, respectively, and are cross-linked with three disulfide bridges. The sequences have high homology to those of toxins I and II from Anemonia sulcata and anthopleurin-A and -B from Anthopleura xanthogrammica.