大叶茜草化学成分的研究

自大叶茜草Rubia schumanniana Pritz的根中分离到五种化学成分,其中一个经光谱及化学方法测定,证明结构为3′-甲氧羰基-4′-羟基-6,6-二甲基萘骈(1′,2′-2,3)吡喃,是新化合物,命名为大叶茜草素(rubimaillin)。另外四个为已知成分,其中三个为蒽醌类化合物,分别鉴定为1-羟基-2-羟甲基蒽醌,1-羟基-2-甲基蒽醌及1,4-二羟基-2-甲基蒽醌,另一为β-谷甾醇。     

茜草中蒽醌类成分的研究

从茜草Rubia cordifolia L.根的乙醇提取物中分得七个蒽醌类化合物,经理化性质及光谱分析,分别鉴定为1,3,6-三羟基-2-甲基蒽醌(Ⅰ),1-羟基蒽醌(Ⅱ),1,2,4-三羟基蒽醌(Ⅲ),1,3,6-三羟基-2-甲基蒽醌-3-O-β-D-吡喃葡萄糖甙(Ⅳ),1,2-二羟基蒽醌-2-O-β-D-吡喃木糖(1→6)-β-D-吡喃葡萄糖甙(Ⅴ),1,3-二羟基-2-羟甲基蒽醌-3-O-β-D-吡喃木糖(1→6)-β-D-吡喃葡萄糖甙(Ⅵ)及1,3,6-三羟基-2-甲基蒽醌-3-O-β-D-吡喃木糖(1→2)-β-D-(6'-O-乙酰基)吡喃葡萄糖甙(Ⅶ).其中Ⅶ为一新化合物。     

茜草化学成分和抗癌活性研究

目的:研究茜草醋酸乙酯提取物的化学成分和测定其抗癌活性。方法:用硅胶柱色谱分离化学成分,利用各种光谱法确定其化学结构。采用MTT法测定体外抗癌活性,细胞株采用LH1210腹水癌细胞。结果:茜草醋酸乙酯提取物显示体外抗癌活性,从茜草醋酸乙酯提取物低极性部分中分离出6个单体化合物,其结构分别为:β-谷甾醇(Ⅰ)、二氢大叶茜草素(Ⅱ)、大叶茜草素(Ⅲ)、2-甲氧酰基-2,3-环氧基-3-异戊烯基-1,4-萘醌(Ⅳ)、大黄素甲醚(Ⅴ)、齐墩果酸(Ⅵ)。结论:化合物Ⅴ首次从该植物中分离得到,化合物Ⅳ显示了很强的抗癌活性。     

巴戟天抗衰老活性成分研究

目的研究巴戟天(Morinda officinalis)活性部位的化学成分。方法用色谱法分离,用波谱法对化合物结构进行鉴定。结果从巴戟天活性部位中分出5个化合物,分别为甲基异茜草-1-甲醚(Ⅰ)、2-羟基-1-甲氧基蒽醌(Ⅱ)、7-羟基-6-甲氧基香豆素(Ⅲ)、异嗪皮啶(Ⅳ)、2-醛基蒽醌(Ⅴ)。结论化合物Ⅳ为首次从该属植物分离得到,化合物Ⅴ为首次从该种植物分离得到。     

毛线柱苣苔化学成分的研究

从毛线柱苣苔(Rhynchotechum vestitum Hook.f.et Thoms.)根和茎中分得五种脂溶性成分,晶Ⅰ为β-谷甾醇(Ⅰ),晶Ⅱ为羽扇豆醇(lupeol,Ⅱ),其余三种为蒽醌化合物,晶Ⅲ和晶Ⅳ分别鉴定为甲基异茜草素-1-甲醚(rubiadin-1-methylether,Ⅲ)和甲基异茜草素°(rbuiadin,Ⅳ),晶V为一新化合物,经光谱分析初步推定其结构为1,6-二羟基-2-甲基-7,8-二甲氧基-9,10-蒽醌,命名为毛线柱苣苔蒽醌(rhynchotechol,Ⅴ)。     

红芽大戟化学成分的研究

目的研究茜草科植物红芽大戟Knoxia valerianoides Thorel et Pitard的化学成分。方法采用各种色谱技术进行分离纯化，经光谱数据分析鉴定其结构。结果从红芽大戟中分离得到2个蒽醌类化合物：1,3,5-三羟基-2-乙氧甲基-6-甲氧基蒽醌(I)及1,3-二羟基-2-乙氧甲基-蒽醌(II)。结论化合物I为新成分。II为从本植物首次发现。     

茜草中抗菌活性成分的研究

从茜草根中分得十二个化合物。通过理化性质及光谱分析,确定了八个已知化合物和一个新化合物(Ⅴ),Ⅴ的结构为1,3,6-三羟基-2-甲基蒽醌-3-O-(O-6′-乙酰基)-β-D-吡喃葡萄糖甙(▽)。     

中药红泽兰化学成分的研究

本文报道从中药红泽兰(爵床科马兰属植物垂序马兰StrobilanShes japonicusⅠ的全草)中分离出的黄酮和甾醇四种成分。经化学及光谱分析鉴定其中之一为新黄酮甙(Ⅱ),命名为红泽兰甙(strobilanthin),即5,7-二甲氧基-4′-羟基黄酮-4’-0-芹糖甙;另一系首次直接从天然界中分得的黄酮化合物(Ⅰ),为前者的甙元即5,7-二甲氧基-4’-羟基黄酮;其余两种均首次从马兰属植物中分出,分别为豆甾醇(Ⅲ)和豆甾-8(14)-烯-3-醇(Ⅳ)。     

滇黄芩中新黄酮成分的结构研究

从唇形科植物滇黄芩Scutellaria amoena C.H.Wright的根中分得八种黄酮类成分(Ⅰ～Ⅷ)。经理化常数测定、光谱分析和化学反应证明,Ⅰ和Ⅱ为新化合物,其结构分别为(2S)-2′,5,6′-三羟基-7-甲氧基双氢黄酮-2′-O-β-D-葡萄吡喃糖甙(Ⅰ)和(2 R,3 R)-2′,3,5,7-四羟基双氢黄酮(Ⅱ);其余六种为已知化合物,分别鉴定为(2S)-5,7,8-三羟基双氢黄酮(Ⅲ)、(2S)-2′,5,6′,7-四羟基双氢黄酮(Ⅳ)、(2 R,3 R)-2′,3,5,6′,7-五羟基双氢黄酮(Ⅴ)、2′,5,6′,7-四羟基黄酮(Ⅵ)、去甲汉黄芩素(Ⅶ)和千层纸甲素(Ⅷ),此六种化合物均为首次从该植物中得到。     

溪黄草甲素的结构研究

从溪黄草Rabdosia serra(Maxim.)Hara干叶、茎中共分得八个化合物,其中化合物Ⅲ～Ⅷ经鉴定分别为excisanin A(Ⅲ),kamebakaurin(Ⅳ),2α-羟基乌苏酸(Ⅴ),β-谷甾醇(Ⅵ),乌苏酸(Ⅶ)和β-谷甾醇D-葡萄糖甙(Ⅷ)。Ⅰ为新化合物,经光谱分析和衍生物制备证明其结构为1,14-二羟基,7,20,19,20-二环氧-16-贝壳杉烯-15-酮,命名为溪黄草甲素。药理实验表明化合物Ⅰ,Ⅲ和Ⅳ对Hela细胞具有显著的抑制作用。     

Antifungal chalcones from Maclura tinctoria

Five prenylated flavonoids, including one new natural product, were isolated from an ethanol extract of the leaves of Maclura tinctoria (L.) Gaud. The new compound has been characterized as 2',4',4,2'-tetrahydroxy-3'-[3'-methylbut-3'-enyl]chalcone (1). The known compounds were identified as 2',4',4-trihydroxy-3'-[3'-methylbut-3'-enyl]chalcone (isobavachalcone) (2), 4,2'-dihydroxy-2'-[1-hydroxy-1-methylethyl]-2',3'-dihydrofurano[4',5':3',4']chalcone (bakuchalcone) (3), 4,4',5'-trihydroxy-6',6'-dimethyldihydropyrano[2',3':5',6']chalcone (bavachromanol) (4), and 5,7,3',4'-tetrahydroxy-6,8-diprenylisoflavone (6,8-diprenylorobol) (5). All the isolated compounds were evaluated against the AIDS-related opportunistic fungal pathogens, Candida albicans and Cryptococcus neoformans. Compound 2 was active against both yeasts.     

PCB methyl sulphones in rat liver after exposure to PCB (Clophen A50): analysis and radiosynthesis of selected methylsulphonyl-PCBs.

1. The hepatic metabolism of polychlorinated biphenyls (PCBs) and formation of PCB methyl sulphone metabolites (MeSO2-PCBs) was determined in the male Sprague Dawley rat 1, 2, 4 or 8 weeks after dosage with Clophen A50 (a commercial PCB mixture). 2. The total concentration of the PCB congeners examined (sigmaPCB) decreased during the experimental period, from 40 microg g(-1) lipid (l.w.) after 1 week to 4 microg g(-1) l.w. after 8 weeks. A 50% decrease of PCB in the liver were estimated to be 28, 13 and 11 days for 2,2',4,4',5,5'-hexachlorobiphenyl (CB153), 2,2',3,3',4,4',5-heptaCB (CB170) and 2,2'3,4',5,5',6-heptaCB (CB187), respectively. 3. The total MeSO2-PCB (sigmaMeSO2-PCB) concentration increased from 800 to 1,020 ng g(-1) l.w. during the first 2 weeks of treatment and thereafter a decrease to 120 ng g(-1) l.w. after 8 weeks. The relative concentration of both 3'-MeSO2-2,2',4,4',5-pentaCB (3'-MeSO2-CB101) and 3'-MeSO2-2,2',3,4,5'-pentaCB (3'-MeSO2-CB87) in rat liver showed significant increases during the 8 weeks. In contrast, the relative concentrations of 4-MeSO2-2,4',5,5-tetraCB (4-MeSO2-CB64), 3-MeSO2-2,3',4',5-tetraCB (3-MeSO2-CB70) and 4-MeSO2-2,2',3,4,5',6'-hexaCB (4'-MeSO2-CB132) decreased significantly. 4. A route for the synthesis of radiolabelled MeSO2-PCBs was developed employing the 'Pummerer reaction' to convert methylthio-PCBs (MeS-PCBs) to the corresponding mercapto-PCBs (SH-PCB). The SH-PCBs were methylated with radiolabelled methyl iodide and the resulting sulphides oxidized to yield the corresponding MeSO2-PCBs. Using this approach, 3-[14C]-MeSO2-2,2',4',5,5',6-hexaCB (3-[14C]-MeSO2-CB149), 4-[14C]-MeSO2-2,2',4',5,5',6-hexaCB (4-[14C]-MeSO,-CB149), 3'-[14C]-MeSO2-CB101, 4'-[14C]-MeSO2-2,2',4,5,5'-pentaCB (4'-[14C]-MeSO2-CB101) and 4'-[3H]-MeSO2-CB101 were synthesized in quantitative radiochemical yields.     

A facile synthesis and anticancer activity evaluation of spiro[thiazolidinone-isatin] conjugates

The synthesis and evaluation of the anticancer activity of 3'-aryl-5'-arylidene-spiro[3H-indole-3,2'-thiazolidine]-2,4'(1H)-diones and spiro[3H-indole-3,2'-thi-azolidine]-2,4'(1H)-dione-3'-alkanoic acid esters were described. The structure of the compounds was determined by (1)H and (13)C NMR and their in vitro anticancer activity was tested in the National Cancer Institute. Among the tested compounds, (5'Z)-5'-(benzylidene)-3'-(4-chlorophenyl)spiro[3H-indole-3,2'-thia-zolidine]-2,4'(1H)-dione (IIa) and (5'Z)-3'-(4-chlorophenyl)-5'-[4-(1-methylethyl)-benzylidene]spiro[3H-indole-3,2'-thiazolidine]-2,4'(1H)-dione (IIb) were superior to other related compounds.     

Nigerasperones A approximately C, new monomeric and dimeric naphtho-gamma-pyrones from a marine alga-derived endophytic fungus Aspergillus niger EN-13

Three new naphtho-gamma-pyrones, 5-hydroxy-6,8-dimethoxy-2-hydroxymethyl-4H-naphtho[2,3-b]pyran-4-one (1, nigerasperone A), 3,3'-dihydro-2,2',5,5'-tetrahy-droxy-8,8',10,10'- tetramethoxy-2,2'-dimethyl-(6',9-bi-4H-naphtho[1,2-b]pyran)-4,4'-dione (2, nigerasperone B), and 3'-hydro-2',5,5',8-tetrahydroxy-6,6',8'-trimethoxy-2,2'-dimethyl-(7,10'-bi-4H-naphtho[2,3-b]pyran)-4,4'-dione (3, nigerasperone C), together with nine related known compounds were characterized from Aspergillus niger EN-13, an endophytic fungus isolated from the marine brown alga Colpomenia sinuosa. Their structures were elucidated by detailed analysis of spectroscopic data and by comparison with literature reports. In the cytotoxic assay, these compounds did not show remarkable inhibitory effects against A549 and SMMC-7721 tumor cell lines. However, 3 and several known compounds showed weak antifungal activity against Candida albicans and moderate activity on DPPH scavenging.     

Synthesis of pyrazolo[4',3':5,6]pyrano[2,3-d]pyrimidine derivatives for antiviral evaluation

6-Amino-3-methyl-4-(4-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile (1) was used as a precursor for preparation of some novel 3,7-dimethyl-4-(4-nitrophenyl)-2,4-dihydropyrazolo[4',3':5,6]pyrano[2,3-d]pyrimidine derivatives 3-6, and some of their corresponding N(2)- and C(5)-S-acyclic nucleosides 7 and 8. Furthermore, the preparation of 5-amino-1-[3,7-dimethyl-4-(4-nitrophenyl)-2,4-dihydropyrazolo[4',3':5,6]pyrano[2,3-d]pyrimidin-5-yl]-1H-pyrazole derivatives 10-16 were described. Some of the prepared products were selected and tested for antiviral activity against Herpes Simplex Virus type-1 (HSV-1).     

Dihydrochalcones from Piper longicaudatum

Bioactivity-guided fractionation of an ethanolic extract of the leaves and twigs of Piper longicaudatum Trelease & Yunker (Piperaceae) resulted in the isolation of one new (1) and three known (2-4) dihydrochalcones. The known compounds are: 2',6'-dihydroxy-4'-methoxydihydrochalcone (2), 2',6',4-trihydroxy-4'-methoxydihydrochalcone (asebogenin) (3), and 2'-hydroxy-4'-methoxy-2'-[1-hydroxy-1-methylethyl]-2",3"-dihy- drofurano[4",5":5',6"]-3"-[2-hydroxy-5-methoxycarbonylphe- nyl]dihydrochalcone (piperaduncin B) (4). The new compound is 2'-hydroxy-4'-methoxy-2"-[2-hydroxy-5-methoxycarbonyl- phenyl]-furano[4",5":5',6']-dihydrochalcone (longicaudatin) (1). Compounds 1-4 were tested for antibacterial activity against S. aureus and methicillin-resistant S. aureus (MRSA); only compound 3 showed inhibitory activity (IC50 of 10 and 4.5 micrograms/ml, respectively).     

Newer substituted benzoxazepinyl-quinazolinones as potent antipsychotic and anticonvulsant agents

3-Amino-[2'-substitutedaryl-3'-substitutedarylaminomethylene-2',3'- dihydro-1',5'-benzoxazepin-4'-yl]-2-methyl-quinazolin-4(3H)-ones 11-18 and 3-amino-[2'-substituted aryl-3'-substitutedaryl-azo-2',3'- dihydro-1',5'-benzoxazepin-4'-yl]-2-methyl-quinazolin-4(3H)-ones 19-26 were synthesized from 3-amino-[2'-substitutedaryl-2',3'-dihydro-1',5'- benzoxazepin-4'-yl]-2-methyl-quinazolin-4(3H)-ones 7-10 by Mannich's reaction and by diazotisation, respectively, on the 3rd position of the benzoxazepine ring of the compounds 7-10. The newly synthesized compounds showed potent antipsychotic and anticonvulsant activities.     

Spiro hydantoin aldose reductase inhibitors derived from 8-aza-4-chromanones

A series of spiro hydantoins derived from 8-azachromanones (2,3-dihydro-4H-pyrano[2,3-b]pyridin-4-ones) has been prepared and tested for aldose reductase inhibitory activity. The standard Bucherer-Bergs conditions had to be drastically modified to increase yields from less than 1% to an acceptable 50% range. One of the most potent compounds was cis-6'-chloro-2',3'-dihydro-2'-methylspiro[imidazolidine-4,4'-4'H- pyrano[2,3-b]pyridine]-2,5-dione; resolution of this compound showed that the 2'R,4'S enantiomer 16 was the most active spiro hydantoin in this series with an IC50 of 7.5 x 10(-9) against human placenta aldose reductase.     

Fluorine-containing heterocycles: synthesis and some reactions of new 3-amino-2-functionalized-6-(2'-thienyl)-4-trifluoromethylthieno [2,3-b]pyridines

3-Cyano-6-(2'-thienyl)-4-trifluoromethylpyridine-2(1H)-thione (2) was prepared and reacted with chloroacetone or phenacyl bromide to yield the 2-acetyl or benzoyl-3-amino-6-(2'-thienyl)-4-trifluoromethylthieno[2,3-b]pyridines (3a, b). In contrast, the reaction of 2 with chloroacetamide or its N-aryl derivatives gave the corresponding 2-carbamoylmethyl thiopyridines 4a-c. Upon treatment of these educts with K2CO3 or C2H5ONa in ethanol, they underwent intramolecular Thorpe-Ziegler cyclization to afford 3-amino-2-carbamoyl-6-(2'-thienyl)-4-trifluoromethyl-thieno[2,3-b]pyridine (5a) and its N-aryl analogs 5b, c. Compounds 5a-c underwent some reactions to yield new pyrido[3',2':4,5]thieno[3,2-d]pyrimidines and pyrido[3',2':4,5]thieno[3,2-d][1,2,3] triazines.     

New prenylchalcones from the hops of Humulus lupulus

Two new prenylchalcones, xanthohumol C and D, together with two known prenylchalcone derivatives, xanthohumol (1) and 5'-(2'-hydroxyisopropyl)-dihydrofurano-[2',3'-b]-4,4'-dihydroxy-6'-methoxy-chalcone (4) were isolated and identified from the hops of Humulus lupulus L. The structures of xanhohumol C and D were elucidated as 5'-hydroxy-6',6'-dimethyl-dihydropyrano-[2',3'-b]-4,4'-dihydroxy-6'-methoxy-chalcone (2) and 5'-hydroxy-6',6'-dimethyl-dihydropyrano-[2',3'-b]-4',6'-dimethoxy-4-hydroxy-chalcone (3) on the basis of HRFAB-MS, 1D and 2D NMR (HMQC, HMBC) spectroscopic data. Among the new prenylchalcones, compound 2 showed marginal cytotoxic activity against human stomach carcinoma BGC-823 and human hepatic carcinoma HepG2 cells.