小花金挖耳地上部分萜类成分研究

本文首次报道对小花金挖耳地上部分化学成分的研究工作,采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、中压柱色谱和薄层制备色谱方法进行分离纯化,从中分离得到8个化合物:(1R,2S,4S,5R)-2,5-二羟基-p-薄荷烷(1),(1S,2S,4R,5S)-2,5-二羟基-p-薄荷烷(2),(3R,4R,6S)-3,6-二羟基-p-1-薄荷烯(3),5αH-桉烷-4(15),11(13)-二烯-12,8β-内酯(4),5α-羟基-桉烷-4(15),11(13)-二烯-12,8β-内酯(5),2α-羟基-5αH-桉烷-4(15),11(13)-二烯-12,8β-内酯(6),4β-羟基-1α,10βH-伪愈创木烷-11(13)-烯-12,8α-内酯(7),4-羰基-1α,10βH-伪愈创木烷-11(13)-烯-12,8α-内酯(8),利用波谱数据和理化性质鉴定了它们的结构.化合物1-3首次从天名精属植物中分离得到.     

红树尖瓣海莲内生真菌Penicillium sp.J41221的代谢产物及其抗菌活性研究

在生物活性指导下,从一株来源于药用红树尖瓣海莲的内生真菌Penicillium sp.(J41221)中分离鉴定了6个化合物,包括4个四环三萜类化合物和2个甾醇类化合物,结构分别为:11-羰基-12α-乙酰氧基-4,4-二甲基-24-甲烯基-5α-胆甾-8,14-二烯-2α,3β-二醇(1),12α-乙酰氧基-4,4-二甲基-24-甲烯基-5α-胆甾-8-单烯-3β,11β-二醇(2),12α-乙酰氧基-4,4-二甲基-24-甲烯基-5α-胆甾-8,14-二烯-3β,11β-二醇(3),12α-乙酰氧基-4,4-二甲基-24-甲烯基-5α-胆甾-8,14-二烯-2α,3β,11β-三醇(4),啤酒甾醇(5)和(3β,5α,6β,22E)-6-甲氧基麦角甾-7,22-二烯-3,5-二醇(6).其中化合物1为首次从生物中获得,且1和2的波谱数据迄今未见任何报道.抗菌活性结果表明,化合物2和4对金黄色葡萄球菌、大肠杆菌和四联球菌均显示一定的抑制活性,最小抑菌浓度(MIC)分别为5和4.86μmol/L.     

红树尖瓣海莲内生真菌Phomopsis longicolla HL-2232次级代谢产物研究

通过活性追踪的方法,从一株来源于药用红树尖瓣海莲的内生真菌Phomopsis longicolla HL-2232中分离鉴定了5个生物碱类化合物、1个色原酮类化合物以及4个甾醇类化合物,分别鉴定为:6-氨基嘌呤-9-羧酸甲酯(1),腺嘌呤核苷(2),尿嘧啶核苷(3),N,N'-二苯基尿素(4),(2S,2'R,3R,4E,8E,3'E)-2-(2'-羟基-3'-十八碳烯酰胺)-9-甲基-4,8-十八碳二烯-1,3-二醇(5),2-(2'S-羟丙基)-5-甲基-7-羟基对氧萘酮(6),fortisterol(7),(22E)-5α,8α-表二氧麦角甾-6,22-二烯-3β-醇(8),啤酒甾醇(9),β-谷甾醇亚油酸酯(10).其中化合物1为新化合物,化合物5为新天然产物,其碳谱数据至今未曾报道.细胞毒活性表明化合物1~3对肿瘤细胞A549,B16F10,HL-60,MCF-7具有不同程度的抑制活性.其中新化合物1对乳腺癌细胞(MCF-7)的IC50值为14.9μmol·L-1、化合物3对肺癌细胞(A549)的IC50值为8.6μmol·L-1,两者活性强于阳性对照药顺铂.     

稀有植物四川金粟兰化学成分的进一步研究

对稀有植物四川金粟兰(Chloranthus sessilifolius)全草甲醇提取物开展进一步化学成分研究,从中分离得到2个二萜类、1个苯丙素类、1个黄酮类和1个木脂素类化合物.利用多种波谱和光谱技术(如红外、紫外、1D/2D NMR、ECD、HR-ESIMS)结合相关文献中的理化数据确定了它们的结构分别为:(3R,5S,6S,9S,10S,13S)-3,6,13-三羟基-对映松香烷-8(14)-烯-7-酮(1)、3α,15-二羟基-13α-甲氧基-对映松香烷-8(14)-烯-7-酮(2)、p-香豆酰-β-苯乙胺(3)、柚皮素三甲基醚(4)和(3R,4R,3'R,4'R)-6,6'-二甲氧基-3,4,3',4'-四氢-2H,2H'-[3,3']-双色原烯-4,4'-二醇(5).其中,化合物1为新的对映松香烷型二萜,而3~5则均为首次从金粟兰属植物中分离得到的化合物.     

南海肉芝软珊瑚中的次生代谢产物分析

从采自海南岛三亚湾的一种肉芝软珊瑚Sarcopyton sp中分离到1个新的对苯二甲酸二酯衍生物,通过波谱方法和化学转变测定其结构为对苯二甲酸-1-异丁基-4-(2′-乙基-正己基)-二酯(1);另外,还分离鉴定得2个多羟基甾醇,24α-甲基一胆甾-5(6)-烯-3β,7α-二醇(2),24-亚甲基-胆甾-3β,5α,6β-三醇(3)和α-十六酸-鲨肝醇酯(4);化合物2和3对肿瘤细胞有明显抑制作用,4具有升白血球作用。     

传统中药甘遂根中二萜类化学成分的电喷雾质谱研究

应用电喷雾多级串联质谱技术对传统中药甘遂根中的弱极性部分化学成分进行了分析鉴定, 根据串联质谱数据, 共鉴定出39个化合物. 其中包括9个新化合物: 分别为3-O-(2,3-二甲基丁酰基)-13,20-O-双十二烷酰基巨大戟萜醇(1)、3-O-(2,3-二甲基丁酰基)-13-O-癸酰基-20-O-十六烷酰基巨大戟萜醇(2)、3-O-(2,3-二甲基丁酰基)-13-O-十二烷酰基-20-O-[(9Z,12Z)-十八烷-9,12-二烯酰基]巨大戟萜醇(3)、3-O-(2,3-二甲基丁酰基)-13-O-十二烷酰基-20-O-(十八烷-9Z-烯酰基)巨大戟萜醇(4)、甘遂素I(5)、甘遂素J(6)、甘遂素K(7)、甘遂素L(8)和甘遂素M(9).     

黑紫橐吾化学成分的分离与鉴定

利用各种色谱技术对黑紫橐吾的乙酸乙酯萃取部位进行分离纯化, 并且根据一维和二维波谱数据进行结构鉴定. 共分离得到4个呋喃雅槛蓝型倍半萜: 1α-氯-6β-异丁酰基-9-酮-10β-羟基-呋喃雅槛蓝烷(1), 1α-羟基-6β-异丁酰基-9-酮-10β-氢-呋喃雅槛蓝烷(2), 1α-羟基-6β-异丁酰基-9-酮-10α-氢-呋喃雅槛蓝烷(3)和1α,10β-二羟基-6β-当归酰基-9-酮-呋喃雅槛蓝烷(4). 其中化合物1为新化合物, 并且通过X射线单晶衍射确定了绝对构型; 化合物2~4为首次从该植物中分离得到.     

豆荚软珊瑚Lobophytum sp. 的次生代谢产物研究

从海南岛三亚海域采集的软珊瑚Labophytumsp.中分离得五个甾醇苷(1)～(5)。通过波谱分析，确定它们的化学结构依次为3'-O-乙酰基-4-O-[β-D-吡喃木糖苷]-孕甾-20-烯-3β,4α-二醇(1)，4-O-[β-D-吡喃木糖苷]-孕甾-20-烯-3β,4α-二醇(2),4'-O-乙酰基-4-O-[β-D-吡喃木糖苷]-孕甾-20-烯-3β,4α-二醇(3),4'-O-乙酰基-4-O-[β-D-吡喃阿拉伯糖苷]-孕甾-20-烯-3β,4α-二醇(4)和4-O-[β-D-吡喃阿拉伯糖苷]-孕甾-20-烯-3β,4α-二醇(5),其中1为新化合物。体外细胞毒性实验表明：化合物(1),(2)和(5)对SKMG-4,Hep-G2和CNE2三种人体癌细胞具有抑制作用。     

岗稔根五环三萜类化学成分的研究

首次对桃金娘Rhodomyrtus tomentosa根部(岗稔根)的化学成分展开研究,从其甲醇提取物中分离得到8个五环三萜类化合物.上述化合物的结构经一维、二维核磁共振谱和质谱等波谱技术分别鉴定为:23-O-顺式-对-香豆酰基-2α,3β-二羟基齐墩果烷-12-烯-28-酸(1),23-O-反式-对-香豆酰基-2α,3β-二羟基齐墩果烷-12-烯-28-酸(2),3β-O-反式-阿魏酰基-2α,23-二羟基齐墩果烷-12-烯-28-酸(3),3β-O-反式-对-香豆酰基-2α,23-二羟基齐墩果烷-12-烯-28-酸(4),3β-O-顺式-对-香豆酰基-2α,23-二羟基齐墩果烷-12-烯-28-酸(5),山楂酸(6),阿江揽仁酸(7)和2α,3β-dihydroxytaraxer-20-en-28-oic acid(8).其中化合物1和3为新的齐墩果烷型三萜,化合物2,4～6和8为首次从该植物中分离得到.     

南鹤虱中两个新的倍半萜类化合物（英文）

从中药南鹤虱(Fructus carotae)中分离纯化得到7个倍半萜类化合物,分别鉴定为7-ethoxy-4(15)-oppositen-1β-ol(1),11-乙酰氧基-8β-当归酰氧基-15-甲氧基-4α,5α-环氧愈创木烷-3-酮(2),11-乙酰氧基-8β-丙酰氧基-4-愈创木烯-3-酮(3),1-oxo-5α,7αH-eudesma-3-en-15-al(4),1β-hydroxy-4(15),7-eudesmadiene(5),1β-hydroxy-4(15),5E,10(14)-germacratriene(6),1β-hydroxy-4(15),5-eudesmadiene(7).其中化合物1和2为新的化合物,新化合物的结构进一步通过HR-ESIMS,1D NMR和2D NMR等光谱技术确定.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.