488 resultados para PUMILIOTOXIN-A ALKALOIDS
Resumo:
A introdução de espécies invasoras marinhas tem causado danos econômicos e ecológicos consideráveis em todo o mundo. Algumas destas espécies incluindo corais escleractíneos possuem adaptações, tais como metabólitos secundários utilizados para evitar a predação e competição por espaço por outros organismos. Este arsenal químico e as interações entre espécies invasoras e nativas podem causar alterações na distribuição das espécies e na estrutura das comunidades de costões rochosos tropicais. Os objetivos deste estudo foram (1) caracterizar os metabólitos secundários produzidos pelos corais invasores Tubastraea tagusensis e T. coccinea na Baía da Ilha Grande, Brasil, (2) detectar os compostos químicos liberados pelos tecidos de Tubastraea tagusensis in situ utilizando um aparelho submersível; (3) testar no campo os extratos metanólicos produzidos por ambas as espécies de Tubastraea contra a predação por peixes generalistas e assentamento de outros organismos, (4) testar no campo se os compostos químicos produzidos por ambos os corais invasores variaram na concentração ou tipo quando os corais foram colocados próximos de competidores nativos e (5) determinar como as comunidades de costões rochosos da Baía da Ilha Grande foram afetadas pela expansão de Tubastraea coccinea e T. tagusensis em 8 locais estudados durante 2 anos. As principais classes de substâncias encontradas nos extratos metanólicos de Tubastraea foram identificados como esteróis, ácidos graxos, hidrocarbonetos, alcalóides, ésteres e alcoóis, entretanto, o aparelho submersível identificou somente hidrocarbonetos liberados por Tubastraea na água do mar. O extrato metanólico de T. tagusensis reduziu a predação por peixes generalistas e já os extratos de ambas as espécies mostraram efeitos espécie-específicos sobre organismos incrustantes no campo. No experimento de interação competitiva foi detectada a presença de necrose nos tecidos do coral endêmico Mussismilia hispida e isso provocou variação nas concentrações de esteróis, alcalóides e ácidos graxos nos tecidos de Tubastraea. Em contraste, a esponja Desmapsamma anchorata cresceu sobre os tecidos das colônias de ambos os corais invasores. A presença de Tubastraea nas comunidades bentônicas causou uma dissimilaridade média de 4,8% nas comunidades invadidas. Uma forte relação positiva foi encontrada entre a cobertura de Tubastraea e a mudança na estrutura da comunidade da Baía da Ilha Grande. Portanto, os efeitos negativos de ambos os corais invasores são suficientes para acarretar mudanças na estrutura das comunidades bentônicas tropicais.
Resumo:
A biodiversidade brasileira abrange plantas de importância medicinal que podem ser utilizadas na formulação de novos fármacos. Contudo, tem sido reduzida em velocidade alarmante, em função de diferentes ações antrópicas. A cultura de tecidos vegetais propicia a conservação e uso do germoplasma permitindo a obtenção de substâncias de importância medicinal. As leishmanioses são consideradas um problema de saúde pública mundial sendo a espécie Leishmania braziliensis de maior importância epidemiológica no Brasil. Recentemente tem-se registrado aumento da resistência à linha de tratamento usual. Do mesmo modo, o uso indiscriminado de antibióticos levou ao aumento de bactérias multirresistentes, que representam sério risco de infecção. A espécie Annona mucosa (Jacq.) possui substâncias, como acetogeninas e alcaloides, que apresentam atividades antiparasitária e antimicrobiana. Nesse sentido, o objetivo do trabalho foi avaliar o potencial leishmanicida e antibacteriano de extratos de A. mucosa de material produzido in vitro e in vivo. Foi proposto um protocolo de germinação in vitro, ainda não reportada para a espécie, com vistas à obtenção de plântulas axênicas. Em meio WPM foram cultivados explantes hipocotiledonares e foliares em meio MS, suplementados com PIC e diferentes concentrações de KIN, BAP ou TDZ. Os calos obtidos foram cultivados em meio líquido de mesma composição para a produção de suspensões celulares. Os materiais foram submetidos à extração metanólica e posterior fracionamento em hexano e diclorometano. Para a avaliação da atividade dos extratos sobre L. braziliensis foi usado o modelo in vitro, com a forma promastigota, e in vivo na forma amastigota, a partir do tratamento de macrófagos peritoneais de camundongos infectados com o parasito. Ambas as formas foram tratadas com os extratos por 96 e 48h, respectivamente. A atividade antimicrobiana foi avaliada por macrodiluição do extrato em Mueller-Hinton, sendo avaliado o crescimento das cepas após 16h de incubação a 48C. A germinação in vitro da espécie foi alcançada em substrato vermiculita estéril umedecido com solução de sais do meio MS, com taxa média de 85%. A maior produção de calos friáveis foi obtida em meios contendo KIN, com potencial uso para cultivo em suspensões celulares. Os extratos do material in situ e in vitro apresentaram atividade leishmanicida, apesar da toxicidade para macrófagos. Culturas de células em suspensão apresentaram potencial leishmanicida in vitro e redução da infecção em macrófagos. Os extratos do material avaliado apresentaram atividade antimicrobiana seletiva, com inibição do crescimento de Streptococcus pyogenes e Bacillus thurigiensis em diferentes concentrações avaliadas. Os métodos biotecnológicos empregados permitiram a obtenção de materiais com propriedades medicinais para as atividades leishmanicida e antibacteriana, assim como o material in vivo, constituindo este estudo o primeiro relato para as atividades propostas em A. mucosa.
Resumo:
Cleome dendroides é uma espécie endêmica da Mata Atlântica dos estados do Rio de Janeiro e Espírito Santo, bioma alterado por intensa atividade antrópica, o que constitui uma ameaça à preservação de suas populações. Não existem estudos dos pontos de vista fisiológico, biotecnológico, fitoquímico ou farmacológico sobre a espécie. Considerando-se o perfil fitoquímico e o potencial medicinal do gênero, torna-se relevante definirem-se protocolos para a produção de plantas e metabólitos de C. dendroides utilizando diferentes sistemas de cultivo in vitro. No presente trabalho, foram realizados estudos sobre a germinação in vivo da espécie, avaliando-se a influência do substrato, temperatura e luz. Não se observou qualquer tipo de dormência, sendo as temperaturas de 20, 25 e 20-30C, em areia ou vermiculita, apropriadas para a germinação in vivo. Definiu-se também uma metodologia eficiente de germinação sob condições in vitro, e as plântulas obtidas foram utilizadas como fonte de explantes para os estudos de propagação in vitro. A resposta morfogênica foi avaliada considerando-se a origem e tipo do explante, tipos e concentrações de reguladores de crescimento e número de subculturas. A metodologia empregada mostrou-se eficiente para a produção de brotos e manutenção de estoques de plantas in vitro que serviram como fonte de explantes. A melhor condição para a propagação in vitro foi definida em meio solidificado contendo BA, independentemente do tipo de explante e da origem. Os brotos obtidos foram alongados, enraizados e aclimatizados. Também foi estabelecida a cultura de raízes e a regeneração de brotos a partir destas culturas. Avaliou-se o efeito da origem do explante, assim como dos tipos e concentrações de fitorreguladores sobre a proliferação de raízes e a regeneração de brotos. O fitorregulador AIB propiciou maior multiplicação das raízes, enquanto BA mostrou-se eficiente na regeneração de brotos a partir das raízes recém-formadas. Foi estabelecido ainda um protocolo de cultura de calos e de suspensões celulares. Avaliou-se o efeito da origem e do tipo de explante, dos tipos e das concentrações de fitorreguladores sobre a calogênese. A combinação de PIC com KIN foi a mais eficiente para a indução de calos em explantes de plântulas obtidas a partir de germinação in vitro, produzindo calos que foram mantidos por pelo menos dois anos. As suspensões celulares também foram estabelecidas em meio contendo PIC + KIN, mantendo uma produção de biomassa de cerca de cinco vezes o peso fresco inicial por três sucessivas subculturas. Análises histoquímicas e fitoquímicas revelaram a presença de alcaloides nos calos e nas suspensões celulares. Foram realizadas análises fitoquímicas de plantas de campo, plantas aclimatizadas, plantas mantidas em estoque in vitro e culturas de raízes, as quais indicaram a presença de derivados de glicosinolatos. Os resultados demonstraram a viabilidade de produção de material vegetal de C. dendroides por meio de métodos biotecnológicos e a produção in vitro de metabólitos de importância medicinal
Resumo:
A study was carried out to determine the effect of 10 or 20% leaves or seeds in the diet of Penaeus monodon , and the extent to which local ipil-ipil (Leucaena leucocephala ) could replace head shrimp meal. A brief description is given of the experimental methodology, and details of composition of the diet, proximate chemical composition of the diets, mean weight gain and survival of Penaeus monodon larvae fed shrimp head meal and ipil-ipil as protein sources, are presented. Mean weight gains for all groups were poor and not statistically significant. Survival rates for those fed 10% ipil-ipil were significantly higher than those fed 20% diets. Wherever the survival rate was high, mean weight gain was low and vice versa. The presence of the toxic alkaloids mimosine in ipil-ipil could have caused the low survival rate.
Resumo:
利用电喷雾串联质谱(ESI-MSn)系统地研究了乌头属植物和中药煎煮液中的乌头碱型生物碱的质谱行为。实验表明,ESI-MSn不仅是一种灵敏的药用植物中乌头生物碱的分析方法,也是研究中药配伍规律和阐释中药复方合理内涵的有效工具。低能诱导碰撞解离肠导下,具有乌头碱骨架类型的生物碱断裂规律相似:丢失C8乙酰基或长链脂肪酰基是它们在MSZ中的特征断裂,在MS3和MS4中丢失1-4CH3OH,1-3H2O,CO,BzOH,CH3(N)或C2H5(N)是其他所有可能的断裂方式,并且结构的微小差别也能在串联质谱中得到反映。利用这些规律分析了生附子、生草乌、生草乌花、生白山草乌和制雪上一支蒿中的生物碱,我们不仅发现所有已知的化合物,还部分表征了50余种新化合物,其中具有15C,17C,19C和ZOC饱和或不饱和脂肪酰基,以10-OH-中乌头碱和10-OH-乌头碱为骨架的脂碱以及三脂型脂碱为首次在乌头属植物中发现。该结果提出了脂类生物碱在乌头属植物中普遍存在的可能性。另一方面,我们发现中药煎煮液具有缓冲溶液的性质,酸性和糖是影响剧毒性双酯型生物碱水解的两个因素。在pH5.0-5.5和糖的存在下,大部分双酯型生物碱水解为苯甲酰单酯型生物碱,少部分被转为脂碱,在pH2.8到3.5之间(半夏等与附子禁用中药煎煮液的pH),双酯型生物碱十分稳定,既不水解,也不转为脂碱。这样,我们不仅解释了传统中医药配伍理论的合理内涵,也表明她可能.存在着不足。此外,脂碱难溶于水,大部分脂碱煎煮后仍残留在药材组织中。最后,为评价脂碱的抗癌效果,我们用在水相下合成了8-棕榈酰-苯甲酰乌头原碱,体外实验表明,0.001mg/ml的8-棕榈酰-苯甲酰乌头原碱对肝癌细胞SMMC-7721和黑色素瘤细胞B16即具有很强的杀伤作用,并且提示它们可能具有不同的作用机制。
Resumo:
首先,利用现代软电离质谱技术--一电喷雾质谱技术以及电喷雾源内碰撞诱导解离(CID)技术,对传统中药--一黄连中的生物碱类化合物小聚碱及其同分异构体表小粟碱化合物的质谱碎裂机理进行了详细研究,实验结果表明,随着碰撞能量的变化,两者的质谱碎裂规律具有明显的差异,据此,建立了简便、快速、准确的小巢碱和表小聚碱两种同分异构体化合物区分的质谱新方法,为该类药材及其相应的中药制剂的质控提供了有效的手段和方法。其次,还利用电喷雾多级串联质谱(ESI-MSn)技术,系统地研究了传统中药--一黄连中生物碱类化合物的质谱碎裂规律,我们通过一级质谱的数据,获得了黄连中生物碱类化合物的分子量信息,并对其中五个已知的生物碱进行了初步的确认,同时,通过一级质谱的结果,首次在黄连中发现的分子量为366的未知生物碱类化合物,并通过电喷雾多级串联质谱技术对上述六种化合物的结构进行了详细的研究,结合标准样品的串联质谱数据和文献资料,确认了五个已知的生物碱类化合物分别为小粟碱、巴马汀、药根碱、黄连碱和13-甲基小桨碱,并推断未知生物碱类化合物为13-甲基巴马汀,建立了黄连中生物碱类化合物简便、快速的质谱分析表征新方法,并为其他传统中药中生物碱类化合物的分析与表征积累了重要的理论数据,更重要的是建立了传统中药中未知生物碱类化合物确认和结构分析的质谱方法。此外,还利用量子化学DFT-B3LYP方法,6-31G(d)基组,详细研究了传统中药黄连中小璧碱分子的质谱碎片的相对稳定性。并通过对结合能的理论计算,探讨 质谱碎裂过程中关键基团的相对活性。结合几何参数比较和前线分子轨道分析等方法,从理论上解释了小聚碱化合物的质谱碎裂规律的合理性、分子结构特征及基团活性等,为研究该化合物的药效作用机理,以及药物分子的全合成提供理论依据。同时,还利用电喷雾质谱和薄层层析等方法,对含有黄连的传统复方--一半夏泻心汤进行了初步的考察研究,通过复方中黄连的阴、阳性溶液对比分析,发现在半夏泻心汤中主要的生物碱类化合物,如:小聚碱、巴马汀、药跟碱、黄连碱在复方煎煮过程中在仅仅表现在数量的变化,而没有质的变化,进一步揭示了在半夏泻心汤复方中黄连中的生物碱类化合物的变化规律,为阐明传统复方的药效物质基础提供了科学依据。最后,确定了黄连中生物碱类化合物的毛细管电泳分析的最佳条件,并对黄连中小粟碱化合物进行了定量分析研究,建立了生物碱类化合物毛细管电泳分析的新方法。
Resumo:
电喷雾质谱是一种软电离技术,生物碱分子中均含有氮原子,具有很高的质子亲合势和气相碱度,特别适合电喷雾质谱分析。本文利用电喷雾质谱系统研究了乌头属的几种植物中二菇类生物碱的质谱行为。并且对中药复方中的生物碱成分的化学变化进行探讨,在串联质谱中,乌头碱类生物碱的裂解方式相似。双酷型、三醋型、脂类生物碱在MS2中容易丢失C8乙酸或长链脂肪酸形成特征子离子峰,在进一步CID谱中,在C15位失去CO为其特征。但是单酷型生物碱在串联质谱中碎裂方式与上述几种生物碱有很大差别,例如,在MSZ中主要失去甲醇,还会失去C3位经基,但是不会失去CS轻基。利用这些规律分析了附子及草乌中的生物碱,发现了多种具有特殊取代基的新化合物。以电喷雾质谱为检测手段分析了附子在炮制过程中的成分变化;并且发现了分离提取脂类生物碱的方法。高乌头中的生物碱以C18型为主,同时也包含少量C19乌头碱骨架的生物碱。这两种类型的生物碱在串联质谱中的碎裂规律相似,都容易失去取代基,而生物碱骨架比较稳定,难以碎裂。但是不同位置的取代基失去时所形成的子离子的丰度有很大差别,经过串联质谱可以获取重要的结构信息。并且通过串联质谱确定了刺乌头碱环糊精的包合位点,更正了文献中的错误。关白附的CZ。型海替生型生物碱在串联质谱中的行为与上述生物碱相似,容易失去取代基,但是在失去取代基的同时,常常伴随骨架中C-C键的断裂。由于这些生物碱的结构存在较强的规律,所以很容易表征其中的结构相似的新生物碱。另一方面,我们发现导致白术与附子配伍将导致共煎液中有毒生物碱成分增加,从而解释了八味地黄丸与人参汤导致中毒的原因。并且通过对八味地黄汤的配伍研究,发现起解毒作用的药材为山茱英,解毒机理为抑制了有毒生物碱的溶出。方中的山药能够抑制双酷型生物碱的水解。
Resumo:
毛壳霉属(Chaetomium)和曲霉属(Aspergillus)真菌产生多种具有生物活性的化合物。为系统阐明两属微生物的次生代谢物,对三种毛壳霉、两种曲霉真菌分别进行固态发酵,以色谱和波谱技术研究发酵物中的成分,分离鉴定了51个化合物,其中23个为新化合物,测试了部分化合物对肿瘤细胞的活性。 1、从螺卷毛壳霉(C. cochloides)固态发酵物中分离鉴定了11个化合物,3个新化合物为螺卷毛壳霉素A~C(1~3)。化合物1、3及dethio-tetra (methylthio) chetomin(4)对Bre-04、Lu-04和N-04细胞株生长抑制的GI50值为0.05~7.0 μg/mL。 2、从印度毛壳霉(C. indicum)固态发酵物中鉴定的三个异喹啉生物碱印度毛壳霉素A~C(12~14)代表两类骨架新颖的异喹啉生物碱。 3、从巴西毛壳霉(C. brasiliense)固态发酵物中鉴定了11个化合物,其中Mollicellins I~J(15~16)、2-Hydroxymethyl-6-methylmethyleugenin(19)为新化合物。化合物16和Mollicellin H(18)对Bre-04、Lu-04、N-04细胞株生长抑制的GI50值在2.5~8.6 μg/mL。 4、从土曲霉(A. terreus)固态发酵物中鉴定了18个化合物。5个为新化合物为Terretonin A~D(24~27)和Asterrelenin(28),24~27为二倍半萜化合物,28为吲哚生物碱。 5、从杂色曲霉(A. versicolor)固态发酵物中鉴定了16个化合物。9个新的化合物Brevianamides K~N (40~43)、Averins A~C (44~46)和Glyanphenines A~B (47~48)代表三种类型的生物碱。 6、综述了1997-2007年间新的二倍半萜的研究进展。 The fungi of the genera Chaetomium and Aspergillus produce various secondary metabolites with biological activities. In order to systematically study the secondary metabolites, the solid-state fermented rice culture of three species of Chaetomium and two of Aspergillus were chemically studied. By the means of chromatograhy and spectroscopy, 55 compounds were isolated and identified, among of them 23 were new ones. The biological activities of some compounds were investigated. 1. From the fungus C. cochliodes, three new epipolythiodioxopiperazines, chaetocochins A-C (1-3) were isolated, together with 8 known ones (4-11). Compounds 1, 3 and 4 showed growth inhibitory effects against cancer cell lines Bre-04, Lu-04 and N-04 with GI50 values from 0.05 to 7.0 μg/mL. 2. Three novel isoquinolines Chaetoindicins A-C (12-14) were isolated and identified from the fungus C. indicum. Chaetoindicin A, Chaetoindicins B-C represented two classes of novel carbon skeletons. 3. Three new compounds, Mollicellins I-J (15-16), and 2-hydroxymethyl-6-methylmethyleugenin (19), were isolated from C. brasiliense. Compound 16 and Mollicellin H (18) showed growth inhibitory effects against cancer cell lines Bre-04, Lu-04 and N-04 with GI50 values from 2.5 to 8.6 μg/mL. 4. Eighteen compounds were isolated from the fungus A. terreus. Terretonin A-D(24 - 27)and Asterrelenin(28) are new compounds belonging to sesterterpoids and indole-ralated alkaloid, respectively. 5. From the fungus A. versicolor, sixteen secondary metabolites, including nine new ones, Brevianamides K-N (40-43), Averins A-C (44-46), and Glyanphenines A-B (47-48), were isolated and identified. Brevianamides K-N (40-43), Averins A-C (44-46), and Glyanphenines A-B (47-48) represented three classes of alkaloids. 6. New sesterterpenes and their bioactivities reported from 1997 to 2007 were summarized.
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本学位论文共有5章。第一章报道白芍的化学成分及芍药苷的微生物转化研究成果;第二章报道天山雪莲的化学成分研究;第三章报道两面针的化学成分研究;第四章报道通关藤的化学成分研究成果;第五章概述了花椒属植物中最近十年报道的新化合物及药理研究情况。 在第1章的第一部分报道了白芍(Paeonia lactiflora Pall.)的化学成分。我们采用正、反相硅胶柱层析等各种分离方法,从白芍的干燥根中共分离出14个化合物,其中1个为新化合物,其结构通过波谱分析证实为没食子酰白芍苷,另外还有2个为首次从该植物中分离得到。第二部分报道了芍药苷的微生物转化生产芍药苷代谢素-I的研究,从15株厌氧菌中筛选出10株有转化活性的菌株,其中短乳杆菌Lactobacillus brevis AS1.12的转化活性最好,对其转化条件进行了初步的筛选,确定了相对合理的转化工艺。 在第2章报道了天山雪莲(Saussurea involucrate Kar.et Kir.)全草乙醇提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR等波谱解析,共分离鉴定了28个化合物,结构类型分属于黄酮、倍半萜和木脂素等,其中2个新倍半萜化合物的结构分别表征为6α-羟基云木香酸6-β-D-吡喃葡萄糖苷和11βH-11,13-二氢去氢云木香内酯8α-O-(6′-乙酰)-β-D-吡喃葡萄糖苷。 第3章报道了两面针(Zanthoxylum nitidum (Roxb.)DC.)干燥根的乙醇提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR等波谱解析以及X-射线单晶衍射,共分离鉴定了16个生物碱,结构类型分属于苯并啡啶类、喹啉类和阿朴啡类等,其中2个新苯并啡啶类生物碱的结构分别表征为二聚双氢两面针碱和丙酮基双氢崖定椒碱。 第4章报道了通关藤(Marsdenia tenacissima (Roxb.) Wight et Arn.)水提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR等波谱解析以及X-射线单晶衍射,共分离鉴定了14个化合物,结构类型均属于C21多羟基甾醇,其中4个新化合物tenacigenoside A, tenacigenoside B, tenacigenoside C和tenacigenoside D的结构分别表征为3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-17β-tenacigenin B (62), 3-O-2,6- dideoxy-4-O-methyl-D-lyxo-hexopyranosly-11α-O- methylbutyryl-12β-O-acetyl-tenacigenin B (63), 3-O-6-deoxy-3-O-methyl-β-D- allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α-O-tigloyl-tenacigenin C (64)和3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α-O-2- methylbutyryl-tenacigenin C (65)。 第5章概述了花椒属植物的化学成分及药理活性研究进展。 This dissertation consists of 5 chapters. The first chapter elaborate the phytochemical investigation of Paeonia lactiflora Pall., and microbial transformation of paeoniforin. The second, third and four chapters elaborate the phytochemical investigation of Saussurea involucrate Kar.et Kir., Zanthoxylum nitidum (Roxb.) DC. and Marsdenia tenacissima (Roxb.) Wight et Arn., respectively. Chapter 5 is a review on chemical constituents and bioactivities of Zanthoxylum species. The part one of chapter 1 focus on the isolation and identification of chemical constituents from P. lactiflora. Fourteen compounds were isolated from the roots of P. lactiflora by repeat column chromatography over normal and reversed phase silica gel. Among them, one is a new compound and the structure was suggested as galloyl-albiflorin by spectral evidence. In addition, two compounds were firstly reported in this plant. The part 2 is about microbial transformation of paeoniforin. Chapters 2, 3 and 4 were isolations and identifications of chemical constituents from S. involucrate, Z. nitidum and M. tenacissima, respectively. From the aerial parts of S. involucrate, 28 compounds including 7 flavonoids and 13 sesquiterpenoids were isolated and identified. Among them, 2 new compounds were characterized as 6α-hydroxycostic acid 6-β-D-glucoside and 11βH-11,13-dihydrodehydro- costuslactone 8α-O-(6'-acetyl)-β-D-glucoside, respectively, by means of spectroscopic analysis. Otherwise, 11 ones were firstly reported from this plant. The third chapter is about the phytochemical investigation of Z. nitidum. Sixteen compounds were isolated and identified. Among them, 2 new benzophenanthridine alkaloids were characterized as 8-acetonyldihydrofagaridine and 1,3-bis(8-dihydronitidinyl)-acetone by spectroscopic analysis. The fourth chapter is about the phytochemical investigation of M. tenacissima. Fourteen compounds were isolated and identified. Among them, 4 new compounds, tenacigenosides A~D, were characterized as 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-17β- tenacigenin B, 3-O-2,6-dideoxy-4-O-methyl-D-lyxo-hexopyranosly-11α-O-methyl butyryl-12β-O-acetyl-tenacigenin B, 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl- (1→4)-β-D-oleandropyranosyl-11α-O-tigloyl-tenacigenin C, and 3-O-6-deoxy-3-O- methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α-O-2-methylbutyryl- tenacigenin C. Chapter 5 is a review on recent progress in bioactive constituents from plants of Zanthoxylum species.
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本论文由四部分组成。第一部分报道了佛手参提取物的化学成分研究,建立了活性成分含量测定的高效液相测定和指纹图谱研究,采用液质联用技术鉴定了主要色谱峰;第二部分报道了丹参及其复方制剂的特征图谱研究;第三部分探讨了两面针生物碱的电喷雾质谱裂解规律,并采用液质联用技术分离鉴定了提取物中的多种生物碱。第四部分概述了液质联用在药物代谢研究中的运用。 第一部分包括第一、第二和第三章。第一章针对佛手参(Gymnadeniaconopsea)块茎的甲醇提取物,采用大孔树脂和反相硅胶柱层析等各种分离方法,共分离鉴定出4 个化合物,通过波谱分析将它们的结构确定为dactylorhin B (1)、loroglossin (2)、dactylorhin A (3)和militarine (4)。这4 个化合物均是首次从佛手参中分离得到的琥珀酸葡萄糖苷类成分。第二章采用高效液相色谱法对西藏、四川、河北、青海和尼泊尔等不同地区产的十个佛手参样品进行腺嘌呤核苷和对羟基苯甲醇的定量分析,结果表明这2 个成份可视为佛手参的特征成分,但也注意到产地不同该2 个特征成分的含量也有所不同。第三章采用标准中药指纹图谱相似度计算软件,以10 个佛手参样品HPLC 图谱的平均值为相似性评价对照模板,对10 个样品进行了相似度评价,并经液质联用分析指认了7 个共有峰,分别为腺嘌呤核苷(1)、对羟基苯甲醇(2)、对羟基苯甲醛(3) 、dactylorhin B(4) 、loroglossin(5)、dactylorhin A(6)和militarine(7)。 第二部分包括第四、第五、第六和第七章。第四章运用电喷雾质谱检测了对照药材和五个不同产地的丹参药材中脂溶性和水溶性成分,系统地探讨了多种成分的电喷雾质谱规律,并以对照药材为标准建立了特征指纹图谱。五个产地的药II材通过与对照药材相对比,采用聚类分析的方法,得到了定性的鉴别与判断。并采用液质联用技术对丹参药材提取液中的化学成份进行分析,推测了九个特征峰,并对六样品的液相色谱图进行了聚类分析。第五章探讨了三七皂苷的电喷雾质谱电离和裂解规律,并采用电喷雾质谱法对三七标准药材,血通片中的皂苷成分进行了分析。第六章运用电喷雾质谱研究复方丹参片提取液的特征图谱,并和单味药材丹参和三七的特征图谱进行了对比研究。并运用HPLC-ESI MSn 分析鉴定了复方丹参片提取液中的化学成分,推测了12 个色谱峰。第七章总结了电喷雾质谱和液质联用技术在丹参药材,三七药材及复方丹参制剂中的运用的优势和局限性。 第三部分(第八章)研究了两面针生物碱中二氢白屈菜红碱(1)、二氢两面针碱(2)、8-酮基二氢白屈菜红碱(3)、8-丙酮基二氢两面针碱(4)、两面针碱(5)、和1,3-二(8-二氢两面针碱)丙酮(6)等六个苯并菲啶型生物碱的电喷雾质谱裂解规律,其中二氢两面针碱和二氢白屈菜红碱,8-丙酮基二氢两面针碱和8-酮基二氢白屈菜红碱是两对二个甲氧基分别在C-9 和C-10,C-10 和C-11 的同分异构体。实验结果表明,在相同的碰撞能下,这类位置异构体的ESI MS2 质谱二级碎片离子的相对峰度存在很大差异,这可以用于区分该类同分异构体,采用液-质联用可以对两面针的总生物碱提取物中的这些同分异构体加于区分。同时在本实验采用的液相色谱条件下,多种生物碱得到较好的分离,通过和对照品的保留时间,紫外吸收光谱及电喷雾质谱图对照,鉴定了11 个主要色谱峰。 第四部分(第九章)对液质联用技术在药物代谢中的运用进行了综述。 This dissertation consisted of four sections. The first two sections elaborated thephytochemical investigation of the rhizomes Gymnadenia conopsea R. Br., methoddevelopment for rapid identifying and qutifying the chemical condtituent of thistibetant medicine, and the chemical fingerprint analysis of rhizomes of G. conopsea,Salviae miltiorrhiza and P. notoginseng. The third section studied the fragmentationmechanism of six alkaloids from Zanthoxylum nitidium and method development forrapid identifying varieties of alkaloids from the extract of this herbal medicine. Thefourth section reviewed HPLC- MS method in drug metabolism studies. The first section consisted of chapters 1, 2, 3. Chapter 1 elaborated the phytochemicalinvestigation of Gymnadenia conopsea R. Br. Four succinate derivative esters wereisolated from the methanol extract of the rhizomes of G. conopsea through repeatedcolumn chromatography on normal and reversed phase silica gel, their structures weredetermined by ESI-MS, 1D and 2D NMR evidence. They were firstly discoveredfrom this species. In chapter 2, a high-performance liquid chromatography.diodearray detection (HPLC-DAD) method has been firstly developed for quantitation oftwo characteristic constituents, adenosine and 4-hydroxybenzyl alcohol, from theextract of rhizomes of G. conopsea. All 10 samples of G. conopsea contained differentamount of adenosine and 4-hydroxybenzyl alcohol. Adenosine and the4-hydroxybenzyl alcohol can be applied in identification and quality control for theroots of G. conopsea. In chapter 3, a high-performance liquid chromatography.diodearray detection.tandem mass spectrometry (HPLC-DAD-MSn) method has been firstly developed for chemical fingerprint analysis of rhizomes of G. conopsea andrapid identification of major compounds in the fingerprints. Comparing the UV andMS spectra with those of authentic compounds, seven main peaks in the fingerprintswere identified as adenosine, 4-hydroxybenzyl alcohol, 4-hydroxybenzyl aldehyde,dactylorhin B, loroglossin, dactylorhin A and militarine. The Computer AidedSimilarity Evaluation System for Chromatographic Fingerprint of TraditionalChinese Medicine (CASES) was employed to evaluate the similarities of 10 samplesof the rhizomes of G. conopsea collected from Sichuan, Qinghai and Hebei provincesand Tibet autonomous region of China, and Nepal. These samples from differentsources had similar chemical fingerprints to each other. The second section consisted of chapters 4, 5, 6 and 7. In chapter 4,both thecharacteristic spectra of liposoluble tanshinones and aqueous-soluble salvianolic acidswere established by the electrospray ionization mass spectrometry (ESI MS)technique and the differences between standard and crude rhizomes of Salviaemiltiorrhiza Bge. from 5 sources were analyzed. The law of electrospray ion trap mass(ESI ITMS) of typical tanshinones and salvianolic acids is studied.The analysis of the chemical constituent of rhizomes of Salviae miltiorrhiza Bge. byliquid chromatography coupled with mass spectrum (LC/MS) technique wasestablished,and the distances among standard herb and crude herb from 5 sourceswere calculated by clustering analysis. According the DAD spectra and MS2 data,9tanshinones could be speculated. In chapter 5, the character spectra of total saponinsin P. notoginseng extracts were established by ESI ITMS and selective ion monitoring(SIM) technology. The law of notoginsenosides by ESI MS2 was studied. In chapter 6,the characteristic spectra of Compound Danshen Tablet established and compared byESI-MS and HPLC/DAD/MS, 6 known tanshinones and 3 saponins were speculated.In chapter 7, the advantage and disadvantage of the strategy, using the ESI ITMS andLC/MS techniques for study of characteristic spetra of danshen and Compound Danshen Tablet, were summerized. The third section (chapter 8) studied the fragmentation mechanism of six alkaloids,dihydronitidine, dihydrochelerythrine, 8-acetonyl dihydronitidine,8-acetonyldrochelerythrine, nitidine and 1,3-bis (8-dihydronitidinyl)-acetone, by ESIMSn. Tandem mass spectrometry experiments indicated that different substitutionsites of the methoxyl groups at C-9 and C-10 or at C-10 and C-11 determined thedifferent abundances of the MS2 fragmentation ions using the same collision energy.According to the different abundances of MS2 product ions, positional isomericbenzo[c] phenanthridine alkaloids can be differentiated. Moreover, ten constituents inthe crude alkaloids extract from the roots of Zanthoxylum nitidium were rapidlyidentified by high-performance liquid chromatography coupled with tandem massspectrometry (HPLC-MSn), through comparing the retention times and ESI MSn spectra with the authentic standards. The fourth section (chapter 9) is a review on HPLC-MS method development in drug metabolism studies.
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本论文由三个部分组成。第一部分是综述性文章-天然C19-二萜生物碱的结构及其核磁共振波谱。这篇综述参考160余篇文献,将迄今为止发表的230余个天然C19-二萜生物碱按其结构和波谱特征,分为10个类型。重点叙述了每个类型的结构和核磁共振波谱,对一些立体构型与13C-NMR化学位移的关系进行了讨论。最后以表格的形式报导了每个天然C19-二萜生物碱的结构及其植物来源,并把其中170余个收集到的13C-NMR化学位移数据整理成表,作为手册,对鉴定此类化合物大有帮助。第二部分是实验论文--弯啄乌头的化学成分研究。重点报导了弯啄乌头(Aconitum campylorrhynchun Hand-Nazz.)中分离到的一个新生物碱--8-乙酰都啦碱(8-acetyldolaconine)的结构鉴定,并根据DEPT、COSY、COLO等对1H-NMR和13C-NMR的所有信号归属都进行了指定。通过各种图谱还发现这个生物碱的A环同时存在着椅式和船式两种构象导购体。另外还报导了从同一植物的生物碱部分分离到的两个二萜生物碱,它们都是嘟啦碱和aconosine.在非生物碱部分还分离到三个化合物,经鉴定证明是β-谷甾醇、棕榈酸和香豆酸。第三部分也是实验论文--展毛翠雀花中生物碱成分的研究。报导了从展毛翠雀花(Delphinium Kamaonense Var.glabrescens W. T. Wang)中初步分离到的两个生物碱。经IR、NS、1H-NMR和13C-NMR等方法确定结构,证明其中一个是新化合物,命名为展毛翠雀碱(glabredelphinine)。另外一个是前几年发现的二萜生物碱tatsiensine。这两个化合物的A环上都有碳-碳不饱和键,这在天然C19-二萜生物碱中还比较少见。This master's thesis consists of three parts. The first part is a review: The relationship between the chemical structures of natural C19-diterpene alkaloids and their NMR chemical shift data. The C19-diterpene alkaloids were divided into ten types according to their structures and NMR data. Some relationaships between configuration and NMR chemical shift have been discussed. The structures and distributions of more than 230 known C19-diterpene alkaloids and the assignments of 13C-NMR data of the 170 alkaloids of them were listed in tables. The second part is an experimental paper, Studies on the chemical constituents of Aconitum campylorrhynchum. Six compounds were isolated from the roots of title plant. One of them is a new alkaloid. It has been elucidaled as 8-acetyldolaconine by means of IR, MS, 1H-NMR,13C-NMR,DEPT,COSY,COLOC and on the basis of identification with aconosine by saponification. Other five compounds were idenfified as dolaconine, aconosine,β-sitosterol, palmitic acid and p-coumaric acid. The third part is also experimental paper: The alkaloids of Delphinium Kamaonense var.glabrescens. Two alkaloids were isolated from the roots of title plant. One of them, C22H22O6N,m.p.201-3℃,named glabredelphinine, was proved to be a new compound. Its structure has been established as 2(3)-dehydro-6-demethyl-18-delcosine by means of IR, MS, 1H-NMR and 13C-NMR.The other one was identified as tatsiensine by comparising of IR, MS, 1H-NMR and 13C-NMR data with that from the literatute.
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本学位论文报道了西藏产三种藏族传统植物药材的化学成分研究。论文由四章组成,前三章是实验部分,分别报道了尼泊尔黄堇(Corydalis hendersonii Hemsl.)、藏波罗花(Incarvillea younghusbandii Sprague)和全缘叶绿绒蒿(Meconopsis interifolia Franch.)的化学成分研究结果。从这三种青藏高原药用植物中共分离鉴定出33 个化合物,其中1 个是新化合物。第四章概述了罂粟科紫堇属植物的化学和药理研究进展。 第一章为尼泊尔黄堇的化学成分研究。通过正、反相硅胶柱色谱等分离方法从药用植物尼泊尔黄堇的地上部分共分离纯化得到12 个化合物。运用MS、1H-NMR、13C-NMR、DEPT、HMBC、NOESY 等现代波谱学方法将它们的结构鉴定为:刺罂粟碱(1) , 普托品(2) , 新那亭(3) , 斯可任(4) , tetrahydrothalifendine (5) ,9-methyl-decumbenine C (6),tetrahydroberberrubine (7),隐品碱(8),α-别隐品碱(9),6,7-methylenedioxy-1(2H)-oxoisoquinolinone (10),6-丙酮基-5,6 -二氢血根碱(11)和β-谷甾醇(12)。其中化合物6 为新化合物,为首次发现的分子骨架上C-9 位连有甲基的苯肽异喹啉类型生物碱。另外,除化合物1 和2 外,其它9 个生物碱(3~11)均为首次从该种植物中分离得到。同时,我们还对对尼泊尔黄堇中的总生物碱进行了串联质谱分析。 第二章为藏波罗花的化学成分研究。从该药用植物的地上部分共分离得到16个化合物,通过理化常数和波谱数据鉴定为:异佛手柑内酯(1),6-甲氧基当归素(2),欧前胡素(3),花椒毒内酯(4),珊瑚菜素(5),水合氧化前胡素(6),rivulobirin A (7),齐墩果酸甲酯(8),咖啡酸甲酯(9),银桦酸(10),(D)-boschniakinic acid (11),对羟基苯甲酸(12) , tert-O-β-D-glucopyranosyl-(R)-heraclenol (13) , 5-methoxy-8-O-β-D-glucopyranosyloxypsoralen (14),前胡苷V(15)和苯乙醇-O-β-D-吡喃葡萄糖-(1→2)-O-β-D-吡喃葡萄糖苷(16)。所有以上化合物均为首次从该种植物中分离得到。另外我们还首次对藏波罗花挥发油的化学成分进行了气相色谱-质谱(GC-MS)联用分析,共鉴定出39 个挥发性成分。 第三章为全缘叶绿绒蒿化学成分的分离鉴定。从传统藏药材全缘叶绿绒蒿地上部分共分离纯化出8 个化合物。通过理化常数和波谱数据将他们的结构分别鉴定为:去甲血根碱(1),β-谷甾醇(2),3-羟基-齐墩果烷-12(13)-烯-30-酸(3),6-丙酮基-5,6-二氢血根碱(4),木犀草素(5),胡萝卜苷(6),quercetin 3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (7)和普托品(8)。其中化合物1,4 和7 为首次从该种药用植物中分离得到。 第四章为综述,总结和归纳了近年来罂粟科紫堇属植物的化学和药理研究进展。 This dissertation consists of four parts. The first, second and third parts report the studies on the chemical constituents from the medicinal plants of Corydalis hendersonii, Incarvillea younghusbandii and Meconopsis interifolia. The forth part reviews the progress of the studies on Corydalis species. The first chapter is about the isolations and identifications of alkalids from the aerial parts of C. hendersonii which is a traditional Tibetan medicine to treat febrifuge, high blood pressure and hepatitis. A new isoquinoline alkaloid, 9-methyl-decumbenine C (6), together with ten known alkaloids, stylopine (1), protopine (2), canadine (3), scoulerine (4), tetrahydrothalifendine (5), tetrahydroberberrubine (7), cryptopine (8), α-allocryptopine (9), 6,7-methylenedioxy-1(2H)-isoquinolinone (10) and 6-acetonyl-5,6-dihydrosanguinarine (11), and β-sitosterol (12) were isolated. Their structures were elucidated by spectroscopic methods. Furthermore, the total alkaloids were analyzed by ESI-MSn. The second chapter is about the isolations and identifications of chemical constituents from the aerial parts of I. younghusbandii. Sixteen compounds were isolated and purified by normal and reversed phase silica gel column chromatography. By spectral analysis, there structures were identified as isobergapten (1), sphondin (2), imperatorin (3), xanthotoxin (4), phellopterin (5), heraclenol (6), rivulobirin A (7), methyl oleanolate (8), methyl caffeate (9), grevillic acid (10), (D)-boschniakinic acid (11), 4-hydroxybenzoic acid (12), tert-O-β-D-glucopyranosyl-(R)-heraclenol (13), 5-methoxy-8-O-β-D-glucopyranosyloxypsoralen (14), decuroside Ⅴ(15), and phenylethyl-O-β-Dglucopyranosyl-(1→2)-β-D-glucopyranoside (16). All of these compounds were isolated from this plant for the first time.By the way, the chemical components of the essential oil from I. younghusbandii were analyzed by GC-MS for the first time. The third chapter is about the the isolations and identifications of the chemical constituents of M. interifolia. Eight compounds were isolated and identified as norsanguinarine (1), β-sitosterol (2), 3-hydroxyolean-12(13)-en-30-oic acid (3), 6-acetonyl-5,6-dihydrosanguinarine (4), luteolin (5), daucosterol (6), quercetin 3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (7) and protopine (8). The compounds 1, 4 and 7 were isolated from this herb for the first time. The last chapter is a review of the research progress of the studies on Corydalis species, which includes the chemical constituents in this genus and their pharmacology.
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本论文由三章组成。 第一章是关于厚朴中具有α-葡萄糖苷酶抑制活性成分的研究。凹叶厚朴的乙醇提取物显示了较强的α-葡萄糖苷酶抑制活性。为了确定其活性成分,在活性测试的指导下,通过溶剂萃取、树脂吸附和反复硅胶柱层析等分离方法从凹叶厚朴乙醇提取物中分离得到6 个生物碱,并用质谱和核磁共振等波谱方法分别鉴定为:木兰箭毒碱,木兰花碱,鹅掌楸碱,蕃荔枝碱,罗默碱和Lysicamine。应用小肠α-葡萄糖苷酶模型测定了它们对α-葡萄糖苷酶的抑制作用。其中,番荔枝碱和木兰箭毒碱对α-葡萄糖苷酶相对抑制活性最好,分别为60%和62%;其它四个生物碱成分对α-葡萄糖苷酶的抑制活性几乎相当,鹅掌楸碱为46%,罗默碱为51%,Lysicamine 为49%,木兰花碱为51%。 第二章报道了厚朴酚的衍生物及其对α-葡萄糖苷酶的抑制活性。根据糖苷酶抑制剂的结构特点,设计合成了一系列厚朴酚的衍生物。厚朴酚经过Mannich 反应和环氧化及开环反应制备了一系列衍生物,经活性测试发现衍生物活性与取代基关系较大,其中5,5′-diallyl-3-((bis(2-hydroxyethyl)amino)methyl)biphenyl-2,2′-diol 的抑制活性最高,为72%。 第三章综述了厚朴的化学成分及药理活性两个方面的研究进展。 The dissertation consists of three chapters. The first chapter is about the study on the constituents with α-glycosidase inhibitory activity from Magnolia officinalis. The EtOH extracts of M. officinalis Rehd. et Wils showed good inhibitory activity against α-Glucosidase. In order to determine the active compounds, bio-assay was used to guide the isolation. Six known alkaloids were isolated by solvent extraction and repeated silica gel column chromatography, and their structures were identified as liriodenine, anonaine, roemerine, lysicamine, magnoflorine and magnocurarine by spectroscopic methods. The inhibitory activity against α-Glucosidase of these alkaloids was measured with alvine screening model of α-glucosidase. Among them, lysicamine and liriodenine have the best inhibitory activity at 60% and 62%, respectively. The other four alkaloids have close inhibitory activity, from 46% to 51%. The second chapter is about the derivation of magnolol and the inhibitory a ctivity of the derivatives. Seven derivatives of magnolol were prepared by Manni-ch reaction, epoxidation followed by ring-opening reaction. Biological activity as say indicated the inhibitory activity was related to substituting groups. Among them, 5,5′-diallyl-3-((bis(2-hydroxyethyl)amino)methyl)biphenyl-2,2′-diol had the highest activity at 72%. The third chapter is a review on the progress of M. officinalis including chemical constituents and pharmacological activity.
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从新几内亚核桃木的树皮中分离得到的吲哚类喹诺里西定生物碱10-Desbromoarborescidine A,因发现其具有阻滞钙离子通道的活性而倍受关注。10-Desbromoarborescidine A由A、B、C、D四个环组成,只有一个手性中心,是吲哚生物碱中结构较简单的一种,常作为此类生物碱全合成方法的模型化合物。但迄今为止,能高效而简便的实现手性10-Desbromoarborescidine A不对称全合成方法线路不多,大多数以不对称诱导的方式建立其手性中心,手性催化的方式仅有一例金属催化。从逆合成分析可知,Desbromoarborescidine A的全合成可以通过亚胺不对称催化还原进行关键的手性中心构建,而本课题组在之前的研究中通过手性有机小分子催化剂的发展,已将三氯硅烷氢转移还原亚胺发展成了一类简便实用、高效、高对映选择性并具有优良底物适应范围的不对称催化反应,我们希望以这一反应作为关键手段,发展一条Desbromoarborescidine A及其类似物不对称合成新路线。 根据我们设计的新路线,首先成功合成了其关键中间体,然后我们进行了关键的不对称催化尝试。用本实验室已有的高性能有机小分子催化剂虽得到了较好的对应选择性,但是产率很低。同时,为了验证整条线路的可行性,我们也用消旋的中间体进行拉通线路的尝试。但不幸的是,在脱除保护基时遇到了很大困难。尝试换不同的保护基,或改变脱保护基的顺序,都未能成功合成目标产物。究其原因可能是由于吲哚的特殊性造成的,吲哚类亚胺与常规的芳香亚胺有较大的差异,其NH基团无论保护还是不保护,对与其2位相联接的C=N双键均有很大的影响,导致其不对称催化还原难以进行。另外,由于所设计的还原产物含有处在吲哚苄位的胺基,稳定性较差,造成保护基脱除困难。 烯胺C-亚磺酰化反应是本课题组最近发现的一个新反应,之前未见文献报道。本研究对该反应进行了反应条件优化和底物扩展,发现带Cbz,Ac,COt-Bu,CO2Et,Bz等保护基的一系列环状和非环状烯胺在亚磺酸钠、DMAc和MeSiCl3的共同作用下能高效高产率生成β-胺基烯基亚砜类新化合物,为合成多官能团化的烯基亚砜新化合物提供了一条简便实用的途径。 The main constituent of Dracontomelum mangiferum B1, indoloquinolizidine alkaloid 10-Desbromoarborescidine A, has drawn great attention due to its calcium channel blocking activity. Its molecular structure is relatively simple compared with the other alkaloids of the same type, which has only one chiral center, albeit with four cycles A, B, C, and D. This compound is often used as a model target for exploring different strategies for the total synthesis of indole alkaloids. Nevertheless, so far there still lack practical and highly efficient methods for the asymmetric total synthesis of 10-Desbromoarborescidine A. Most of the current available methods rely on stoichiometric asymmetric synthesis for the construction of the chiral center. There is only one example reporting utilization of asymmetric catalysis, but with transition metal complex as the catalyst. Our retrosynthetic analysis shows that catalytic asymmetric reduction of imine could be used as the key step for the construction of the chiral center of Desbromoarborescidine A. Since in the previous studies our group has developed the asymmetric reduction of imines by trichlorosilane into a practical and highly efficient and enantioselective method using newly designed chiral organocatalysts, we hope to apply this method to develop a novel synthetic route for the total synthesis of Desbromoarborescidine A and its analogues in this study. According to the newly designed synthetic route, we first accomplished the synthesis of the key intermediates which was then examined for the critical asymmetric catalysis. The asymmetric reduction using the highly efficient organocatalysts, developed in our lab afforded high ee but poor yield. We tried different reaction conditions to improve the yield, but failed to get any good results. Simultaneously, to vertify the feasibility of the synthetic route we designed, we also tired to go through the route toward the racemic synthesis of Desbromoarborescidine A. But unfortunately, protection and deprotection proved to be big hurdles. All the different protection groups and different sequences of protection and deprotection we tried failed to get us through the designed synthetic sequence and furnish the final product. Most likely, the indole part is the culprit behind the failures.The NH group of the indole, no matter protected or not, may impact the catalytic asymmetric reduction of C-N double bond connected with 2-C. Additionally, the reduction product we designed contains an amino group in the β-position of the indole, which may cause problems due to its instability. C-sulfenylation of enamines is a novel reaction discovered recently by our group, which has not been seen before in the literature. In this study, optimization of the reaction conditions and exploration of the substrate scope were further undertaken for this reaction, which reveal that a series of enamines with N-Cbz, Ac, COt-Bu, CO2Et protection groups could all undergo smooth C-sulfinylations with the comined use of sodium benzene sulphinate, DAMc and MeSiCl3, efficiently furnishing the β-amino vinylsulfoxide products in high yield, affording a practical and highly efficient methods for synthesis of functional vinylsulfoxides.
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An optimization method based on uniform design in conjunction with genetic algorithm is described. According to the proposed method, the uniform design technique was applied to the design of starting experiments, which can reduce the number of experiments compared with traditional simultaneous methods, such as simplex. And genetic algorithm was used in optimization procedure, which can improve the rapidity of optimal procedure. The hierarchical chromatographic response function was modified to evaluate the separation equality of a chromatogram. An iterative procedure was adopted to search for the optimal condition to improve the accuracy of predicted retention and the quality of the chromatogram. The optimization procedure was tested in optimization of the chromatographic separation of 11 alkaloids in reversed-phase ion pair chromatography and satisfactory optimal result was obtained. (C) 2003 Elsevier B.V. All rights reserved.