节点文献
海绵Sarcotragus sp.和中药有柄石韦的次生代谢产物的研究
Studies on the Secondary Metabolites of Marine Sponge Sarcotragus sp. and Chinese Traditional Herbal Medicine Pyrrosia Petiolosa
【作者】 王楠;
【作者基本信息】 沈阳药科大学 , 天然药物化学, 2007, 博士
【摘要】 海洋生物是链状二倍半萜的主要来源,其中Ircinia和Sarcotragus属海绵常常可以特征性地产生一端为呋喃环衍生物,而另一端为特窗酸(Tetronic acid)衍生物的二倍半萜类或者降二倍半萜。具有这样的结构特点的二倍半萜类化合物被称为呋喃型二倍半萜特窗酸(Furanosesterterpene Tetronic Acid,FTA)。研究表明这种类型的化合物往往具有很强的抗微生物、拒食、细胞毒等活性。为了从海洋生物中寻找具有潜在的生物活性的先导物质,我们对采集自韩国西南部Soheuksan岛周围水深20-25m的一批海绵进行了初步的活性筛选。结果表明Sarcotragus属海绵Sarcotragus sp.具有进一步研究的价值。利用BST活性跟踪和核磁共振氢谱双重导向的方法从该动物的甲醇和二氯甲烷的合并提取物中发现了4个对Brine Shrimp有致死活性的部位。对其中的两个部位的次生代谢产物进行了深入研究。利用溶剂萃取、快速反相色谱法、凝胶过滤色谱法以及正相和反相HPLC法分离了32个化合物,其中包括部分无法分离的双键位置异构体。采用1D,2D NMR、HRFABMS、IR、UV等手段鉴定了27个化合物的平面结构。采用CD光谱法、旋光分析法、化学降解法、以及衍生物制备等光谱学和化学手段鉴定了部分化合物的绝对构型。其中19个化合物为未见文献报道的新化合物。首次发现了12个具有新颖的丁二酸酯型重排末端的二倍半萜类成分(化合物5~16);2个极其少见的1,4-二甲氧基取代型FTA(化合物18,19)以及2个同样非常罕见的呋喃环转化为丁烯酸内酯的新化合物异构体(化合物20,22);同时还发现了4个新C21型降二倍半萜异构体(23~25,27)。对于化合物1~4,采用与文献对照旋光值的方法确定了它们的18位的绝对构型。利用化学氧化降解法确定了化合物21,22的18位的绝对构型。化合物23~26的18位的绝对构型则是利用制备它们的PGME衍生物的方法得以确定。采用圆二色谱法确定了化合物27的4位的绝对构型。对2007年以有关呋哺型二倍半萜类化合物(FTA)的研究进展进行了综述。文章并没有试图介绍所有已发表的FTA类成分,而是侧重介绍FTA类化合物的结构变化。将FTA类化合物的结构变化分为3部分分别进行了综述。并对部分结构新颖的化合物来源、结构变化的特点、以及药理作用进行了描述。共介绍FTA类化合物64个,引用文献33篇。本文还对FTA类化合物的结构鉴定方法进行了总结。主要介绍了利用NMR技术以及化学方法对FTA类化合物的结构鉴定方法。同样对FTA的结构中的3部分的不同结构类型的波谱数据分别进行归纳,总结出了利用1H NMR和13C NMR数据来确定FTA类化合物的波谱规律。针对不同位置的手性中心,分别介绍了利用化学方法、光谱方法(CD,[α]Dt)进行绝对构型的确定方法。有柄石韦(Pyrrosia petiolosa(Christ)Ching)始载于《神农本草经》。为水龙骨科(Family Polypodiaceae)石韦属(genus Pyrrosia)植物。和石韦(P.lingua)以及庐山石韦(P.sheareri)一起是中药“石韦”的三种主要来源,三者均为《中华人民共和国药典》收载的正品药材。中医认为石韦性甘味苦,微寒,归肺、膀胱经。具有清肺泄热、利水通淋、清热止血之功效。用于淋病、小便不通、出血及肺热喘咳。属利水渗湿药。另外还有多达6种同属植物作为地区性用药成为了上述三种石韦的替代品。由于石韦属植物种类繁多,在我国分布也十分广泛,长期以来出现了同属不同种药材的混用现象。即使被中国药典收载的三种正品石韦之间在形态学上及化学成分上也存在显著的不同。前人关于有柄石韦的报道较少,关于起作用的物质基础也不十分明确。为此我们对中药有柄石韦进行了系统的化学成分研究。为了进一步地深入研究有柄石韦的化学成分,论文的第四章中综述了2007年4月以前石韦属的药用植物的研究进展。全面地概括了所有石韦属的植物的化学成分的研究状况。并且对其药理作用及临床应用也进行了归纳。引用文献27篇。采用反复硅胶柱色谱、聚酰胺柱色谱、Sephadex LH 20、PTLC、重结晶等手段从有柄石韦的全草的90%乙醇的回流提取物以及其水煎液中分离纯化得到31个化合物。利用1D,2D NMR,MS,IR,UV等波谱手段以及重结晶、酸水解、熔点测定等物理化学手段确定了它们的结构。分别为香草酸(33),原儿茶醛(34),二氢咖啡酸(35),咖啡酸(36),3,4-dihydroxylbenzalacetone(37),4-O-β-D-吡喃葡萄糖基咖啡酸(38),山奈酚(39),山奈酚-3-O-β-D-吡喃葡萄糖苷(40),穗花杉双黄酮(41),(±)圣草酚7-O-β-D-葡萄糖醛酸甲酯(42),(±)圣草酚-7-O-β-D-葡萄糖醛酸乙酯(43),棉子皮亭-7-O-β-D-吡喃葡萄苷(44),山奈酚3-O-β-D-吡喃葡萄糖苷-7-O-α-L-呋喃阿拉伯糖苷(45),棉子皮亭7-O-(6-α-L-呋喃阿拉伯糖苷)-β-D-吡喃葡萄糖苷(46),绿原酸(47),绿原酸甲酯(48),绿原酸乙酯(49),5-caffeoyl-1,3-quinide(50),methyl 3,4-di-O-caffeoyl quinate(51),methyl 3,5-di-O-caffeoyl quinate(52),里白烯(53),24-methylene-9,19-cyclolanost-3β-yl acetate(54),cycloeucalenol(55),α-生育酚(56),β-谷甾醇(57),胡萝卜苷(58),α-D-葡萄糖(59),β-D-葡萄糖(60),蔗糖(61)以及α-D-ethylfructofuranoside(62),5-羟甲基糠醛(63)。其中化合物45为未见文献报道的新化合物;化合物35,37,38,41,49~52,54~56,62为首次从该属植物中分离得到。33,34,36,59,60,63为首次从该植物中分离得到。
【Abstract】 Marine organisms, particularly sponges, have continued to provide a large group oflinear sesterterpenes. Quite a number of these compounds contain aβ-substituted furanring, some times a butenolide, in one terminal and a tetronic acid moiety in the otherterminal. The sesterterpenes were called Furanosesterterpene Tetronic Acids which isoften abbreviated to FTA. They always co-occur with degradation products includingC21, C22 and C24 norsesterterpenes. Sponges of genera Ircinia and Sarcotragus haveproduced a wide variety of FTAs. Studies showed FTAs possessed biological propertiessuch as antimicrobial, anti-inflammation, cytotoxicity, anti-predator, antifouling and etc.In the course of our search for biologically active lead compounds from marineorganisms, sponge Sarcotragus sp. collected at Soheuksan Island in southwestern Koreawhich showed promising activities was chemically studied. Brine shrimp lethality assayand proton NMR co-guided fractionation led to 4 active fractions which displayedcharacteristic FTA resonances in 1H NMR spectra. 2 of the active and structurallyinteresting fractions were intensively studied. Solvent extraction, reversed phase flashchromatography, gel filtration on Sephadex LH 20, and semi-preparative HPLC wereemployed for separation and purification of the metabolites. Structurally elucidation of27 metabolites isolated from the methanol and dichloromethane extracts were aided by1D, 2D NMR, HRFABMS, IR, and UV. Some metabolites, although could notchromatographically resolved from their co-occuring positional isomers, werenevertheless characterized by spectroscopic analysis and chemical degradation. Theabsolute stereochemical features of some metabolites were pinned down by oxidationcleavage, PGME amides preparation, circular dichroic spectroscopy, and specific opticalrotation data comparison. 19 out of the 27 metabolites were new compounds.Compounds 516 possessed an unprecedent succinate terminal which derived from abenzilic rearrangement of tetronic acid moiety. 2 metabolites, 18 and 19, featured a rare1, 4-dimethoxy furan moiety. In compounds 20~22, the furan moiety were oxygenatedinto butenolide which is unusual in FTAs. 23~27 were characterized as C21norsesterterpenes derived from the degradation of tetronic acid terminal.A review titled as "Progress on furanosesterterpenes tetronic acid" was provided. Related literature published up to February 2007 was reviewed and totally 33 referenceswere cited. The article does not try to illustrate all the FTAs reported but placedemphasis on the structural diversity of FTAs. It was organized in a different way fromthose generally adopted. The structure of a FTA was divided into 3 parts, namely, furanterminal (F part), terpene bridge (T part) and tetronic acid terminal (A part). All theFTAs were introduced by their variation in the 3 parts, respectively.The structural identification methods of FTAs were summarized based on 32references in Chapter Three. Similar with the review described above, extensive studieson the NMR data of the 3 parts of FTAs derivatives were carried out, which allows oneto judge different structure variation simply through 1H NMR or/and 13 C NMR spectra.Stereochemistry determination was also discussed. Different chiral sites in FTA maylead to different spectroscopic or chemical strategies, including chemical degradation,PGME method, CD spectroscopy and optical rotation data analysis.The genus Pyrrosia comprises 110 species and over 50 of them have been found inChina. P. petiolosa, which occurs in most places of China, is one of the 3 main sources(P. petiolosa, P. lingua and P. sheareri) of the traditional Chinese herbal medicine"ShiWei" and has been traditionally used for the treatment of nephroptosis and asthma.As the review (up to April, 2007, 27 References cited) in Chapter Four showed, thespecies of this genus are generous in producing flavanoids, triterpenoids and phenolicacids. In order to find the bioactive components against nephroptosis, we isolated 31compounds from the ethanol extracts and the water extracts of this plant via repeatedcolumn chromatography on silica gel, polyamide, PTLC and recrystallization. Theywere identified as vanillic acid (33) , protocatechualdehude (34) , hydrocaffeic acid (35) ,caffeic acid (36) , 3,4-dihydroxylbenzalacetone (37) , 4-O-β-D-glucopyranosylcaffeic acid (38) , kaempferol (39) , kaempferol-3-O-β-D-glucopyranoside (40) ,amentoflavone (41) , (±) eriodictyol-7-O-β-D-glucuronide methyl ester (42) , (±)eriodictyol-7-O-β-D-glucuronide ethyl ester (43) , gossypetin-7-O-β-D-glucopyranoside (44) , kaempferol 3-O-β-D-glucopyranoside-7-O-α-L-arabinofuranoside (45) , gossypetin 7-O-β-D-glucopyranosyl (1→6) -α-L-arabinofuranoside (46) , chlorogenic acid (47) , chlorogenic acid methyl ester (48) ,chlorogenic acid ethyl ester (49) , 5-caffeoyl-1,3-quinide (50) , methyl 3, 4-di-O-caffeoyl quinate (51) , methyl 3, 5-di-O-caffeoyl quinate (52) , diploptene (53) , 24- methylene-9, 19-cyclolanost-3-yl acetate (54) , cycloeucalenol (55) ,α-tocopherol (56) ,β-sitosterol (57) , daucosterol (58) ,α-D-glucose (59) ,β-D-glucose (60) , sucrose (61) , ethyl a-D-fructofuranoside (62) and 5-hydroxymethylfurfural(63) by physico-chemical analysis and their ID, 2D NMR, MS, UV data.Among them, compound 45 was a new compound, and for the first time, the occurrenceof compound 35, 37, 38, 41, 49~52, 54~56, 62 in genus Pyrrosia were demonstrated.Compounds 33, 34, 36, 59, 60, 63 were newly found from this species.
【Key words】 marine sponge; Sarcotragus sp.; secondary metabolites; sesterterpene; furanosesterterpene tetronic acid; FTA; Pyrrosia; Pyrrosia petiolosa; chemical constituents; structural elucidation; natural products;