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1.
Phytochemical investigation of the plant Clerodendrum phlomidis Linn. F. (Lamiaceae) has now led to the isolation of two new flavonoid glycosides (1, 2) together with six known compounds identified as pectolinaringenin (3), pectolinaringenin-7-O-β-d-glucopyranoside (4), 24β-ethylcholesta-5,22E,25-triene-3β-ol (5), 24β-ethylcholesta-5,22E,25-triene-3β-O-β-D-glucopyranoside (6), (2S,3S,4R,10E)-2-[(2′R)-2′-hydroxytetracosanoylamino]-10-octadecene-1,3,4-triol (7) and andrographolide (8) mainly by spectroscopic analysis. Compounds 4 and 68 are reported for the first time from C. phlomidis.  相似文献   
2.
采用高效液相色谱法结合一测多评法测定了隔山消发酵前后2,4-二羟基苯乙酮、2,5-二羟基苯乙酮和白首乌二苯酮等3种苯乙酮类化合物的含量。分别制备发酵前后的隔山消样品溶液,色谱分析中采用Thermo C18色谱柱作为固定相,用不同比例的水(A)、乙腈(B)和甲醇(C)的混合液作为流动相进行梯度洗脱,达到上述3种组分的良好分离。采用二极管阵列检测器在相同的检测波长(265nm处)分别测定3种组分的峰面积。分别用一测多评法(QAMS)和外标法计算所测定组分的含量,结果表明两种计算方法所得结果相似性极高,据此认为在隔山消发酵前后的样品溶液中各组分的质量评价中采用QAMS是可行的。按上述方法分析了同一批隔山消样品12份,取其中6份经发酵处理,对所得结果的平均值进行了比较,未经发酵的样品溶液中2,4-二羟基苯乙酮的质量分数为0.208mg·g^-1、2,5-二羟基苯乙酮的质量分数为0.152mg·g^-1,与经发酵的样品溶液中的质量分数(2,4-二羟基苯乙酮的质量分数为0.235mg·g^-1、2,5-二羟基苯乙酮的质量分数为0.180mg·g^-1)相比呈升高趋势,而白首乌二苯酮的质量分数由未经发酵样品溶液中的0.678mg·g^-1下降为发酵样品溶液中的0.543mg·g^-1。此外,研究结果还表明,不同含量的2,5-二羟基苯乙酮和白首乌二苯酮相对于2,4-二羟基苯乙酮(参照物)的相对校正因子和相对保留时间基本相同。  相似文献   
3.
A pair of unprecedented enantiomers (1a/1b) of cyclohexylethanoid bearing an unusual trioxabicyclo[4.2.1]nonane ring, along with two known structurally related cyclohexylethanoids, (+)-rengyolone (2) and cleroindicin E (3), were isolated from the aerial parts of Clerodendrum bungei. The structures and absolute configurations of the enantiomers were determined by comprehensive spectroscopic analysis, single-crystal X-ray diffraction, and quantum mechanical calculation of the electronic circular dichroic (ECD) spectra. The postulated biogenetic pathway of 1a/1b was also discussed.  相似文献   
4.
In this study, two previously undescribed diterpenoids, (5R,10S,16R)-11,16,19-trihydroxy-12-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl-17(15→16),18(4→3)-diabeo-3,8,11,13-abietatetraene-7-one (1) and (5R,10S,16R)-11,16-dihydroxy-12-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl-17(15→16),18(4→3)-diabeo-4-carboxy-3,8,11,13-abietatetraene-7-one (2), and one known compound, the C13-nor-isoprenoid glycoside byzantionoside B (3), were isolated from the leaves of Clerodendrum infortunatum L. (Lamiaceae). Structures were established based on spectroscopic and spectrometric data and by comparison with literature data. The three terpenoids, along with five phenylpropanoids: 6′-O-caffeoyl-12-glucopyranosyloxyjasmonic acid (4), jionoside C (5), jionoside D (6), brachynoside (7), and incanoside C (8), previously isolated from the same source, were tested for their in vitro antidiabetic (α-amylase and α-glucosidase), anticancer (Hs578T and MDA-MB-231), and anticholinesterase activities. In an in vitro test against carbohydrate digestion enzymes, compound 6 showed the most potent effect against mammalian α-amylase (IC50 3.4 ± 0.2 μM) compared to the reference standard acarbose (IC50 5.9 ± 0.1 μM). As yeast α-glucosidase inhibitors, compounds 1, 2, 5, and 6 displayed moderate inhibitory activities, ranging from 24.6 to 96.0 μM, compared to acarbose (IC50 665 ± 42 μM). All of the tested compounds demonstrated negligible anticholinesterase effects. In an anticancer test, compounds 3 and 5 exhibited moderate antiproliferative properties with IC50 of 94.7 ± 1.3 and 85.3 ± 2.4 μM, respectively, against Hs578T cell, while the rest of the compounds did not show significant activity (IC50 > 100 μM).  相似文献   
5.
研究臭牡丹中黄酮类化合物的最佳提取工艺条件及其抗氧化活性.以提取时间、料液比、提取温度、乙醇体积分数为主要影响因素,以黄酮类化合物提取率为考察指标,确定最佳提取工艺条件,并通过对亚硝酸盐、超氧阴离子自由基、羟自由基的清除效果及对猪油的抗氧化研究其抗氧化活性.结果表明,臭牡丹中黄酮类化合物的最佳提取工艺条件为提取时间2.0h、料液比1∶40(g/mL)、提取温度70℃、乙醇体积分数70%的条件下提取效果最好,臭牡丹中黄酮类化合物在各抗氧化体系中均表现出较强的抗氧化活性,且其作用具有剂量效应关系,其抗氧化活性均强于维生素C.  相似文献   
6.
One new triterpenoid, (3β,11α,19β)‐3‐(butanoyloxy)‐11‐hydroxytaraxast‐20(30)‐ene‐23,28‐dioic acid (clerodendrumic acid; 1 ) was isolated from the hexane extract of the leaves of Clerodendrum glabrum var. glabrum along with heptadecanoic acid ( 2 ). The structure of the new compound was elucidated by interpretation of its NMR (1D and 2D), MS, and IR data. Combined fractions C and D from the column chromatography of the hexane extract exhibited significant antifungal activities (average MIC of 0.10 mg/ml) against Candida albicans and Cryptococcus neoformans. C. albicans was relatively resistant to clerodendrumic acid ( 1 ; MIC 125 μg/ml) and was resistant to heptadecanoic acid ( 2 ; MIC 188 μg/ml). Both compounds had low antibacterial activities against two Gram‐positive and two Gram‐negative bacteria with average MIC values of 157 and 172 μg/ml, respectively. Compounds 1 and 2 were relatively nontoxic against monkey kidney Vero cells in vitro with IC50 values of 202.6 and 108.4 μg/ml, respectively.  相似文献   
7.
A new lupane‐type triterpene named clerodendrumol ( 1 ), i.e., (16α)‐lupa‐12,20(29)‐dien‐16‐ol, together with five known compounds, octacosa‐(5Z,9Z)dienoic acid ( 3 ), tetracosanoic acid ( 4 ), genkwanin ( 5 ), (12S)‐hydroxyoctadeca‐(9Z,13E,15E)‐trienoic acid ( 6 ), and (9S)‐hydroxyoctadeca‐(10E,12E)‐dienoic acid ( 7 ), were isolated from the twigs of Clerodendrum yaundense. O‐Acetylclerodendrumol ( 2 ), a derivative of 1 , was prepared by a standard acetylation procedure applied to compound 1 . The structure of the new compound was elucidated using spectroscopic analysis (NMR and MS) data, and chemical conversions (acetylation and deacetylation). The human breast cancer cell line (MDA‐MB‐231) was sensitive to all test samples, and clerodendrumol ( 1 ) as well as its derivative 2 had good activity (IC50 values 7.5 and 13.2 μM ). Genkwanin ( 5 ) exhibited strong activity on HeLa cell line with IC50 7.8 μM .  相似文献   
8.
Eight compounds were isolated from the leaves of Clerodendrum inerme, including one new rearranged abietane diterpene, crolerodendrum B (1). Their structures were determined by means of spectroscopic methods including one-dimensional and two-dimensional nuclear magnetic resonance (1-D and 2-DNMR), high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) and circular dichroism (CD). The DPPH radical scavenging and cytotoxic activities of isolated compounds against MCF7 (breast), HCT116 (colon) and B16F10 (melanoma) cancer cell lines were evaluated. Compounds 1, 3 and 4 exhibited strong DPPH radical-scavenging effects (ED50 values of 17.6 ± 2.1, 10.1 ± 0.8 and 11.3 ± 0.3 μM, respectively) and 4 showed strong cytotoxicity against the HCT116 cell line (IC50 = 3.46 ± 0.01 μM).  相似文献   
9.
Six new C21 steroidal glycosides 1 – 6 were isolated from the stem parts of Cynanchum bungei Decne . The structures of the new glycosides were determined on the basis of spectroscopic analysis, including 1D‐ and 2D‐NMR and HR‐ESI‐MS techniques as well as by comparison of their spectral data with those of related compounds.  相似文献   
10.
In the previous papers"', we have reported some chemical constituents fromClerodendrum serratum var. amplerghlium Moldenke. A continuation of our studies onthe same plant led to the isolation of a new phenylpropanoid, serratumoside A (l), whichis reported in this paper.Serratumoside A (l) with three known phenylpropanoid glycosides identified asacteoside', mwtinoside' and myricoside', respectively, were isolated from the Cserratum. Compound I was isolated as a brown amorphous powder, laly …  相似文献   
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