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排序方式: 共有565条查询结果,搜索用时 31 毫秒
1.
将金鸡纳碱衍生物双功能催化剂用于有机催化羟基吲哚与靛红的不对称Friedel-Crafts反应, 筛选出最佳反应条件: 催化剂为5%(摩尔分数)6′-脱甲基奎尼丁(1b), 溶剂为四氢呋喃, 反应温度 0 ℃. 以67%~91%的产率和最高达97%的对映选择性获得了苯环上取代的羟基烷基化产品. 拓宽了该反应的催化剂类型和底物范围. 相似文献
2.
Two new quinolone alkaloids, superbusines A (1) and B (2), were obtained from the whole plants of a Chinese medicinal plant, Dianthus superbus var. superbus. Their structures, featuring a glucosyl moiety linked with a rare 2-(hydroxymethyl)-5-(2-hydroxypropan-2-yl)phenol fragment, were determined on the basis of detailed spectroscopic analyses, and the absolute configurations were assigned by time-dependent density functional theory (TD-DFT)-based electronic circular dichroism (ECD) calculations. The two alkaloids were evaluated in a series of bioassays without showing antimicrobial, anti-inflammatory, antioxidant, cytotoxic and α-glucosidase inhibitory properties, while they exhibited slight protection against amyloid-β(Aβ)-induced injury on neuron SH-SY5Y cells. 相似文献
3.
Kai-Hui Sun Xin-Hua Ma Xian-Ming Zeng Zhong-Yue Lin Yu-Mei Cai Hai-Tao Zhang 《Natural product research》2019,33(20):2925-2931
One new indole-type alkaloid, α-L-rhamnopyranosyl-(1→6)-β-D- glucopyranosyl 6-methoxy-3-indolecarbonate (1), together with three known alkaloids (2–4), one aromatic acid (5) and five known saponins (6–10), was isolated from the roots of Clematis florida var. plena. Their structures were established by NMR spectroscopic analysis and acid hydrolysis. In in vivo anti-inflammatory activity, n-butanol extract was found to be potent against ear edema in mice, with inhibition rate of 48.7% at a dose of 800?mg/kg. Furthermore, compounds 8 and 9 obtained from the n-butanol extract exhibited significant anti-inflammatory activities with inhibition rates of 50.9% and 54.7% at a dose of 200?mg/kg. 相似文献
4.
Wen-ting Li Dan Luo Jia-ning Huang Lin-lin Wang Feng-guo Zhang Tao Xi 《Natural product research》2018,32(6):662-667
One new alkaloid, named as acremolin C (1), was isolated from static culture of Antarctic fungus, Aspergillus sydowii SP-1, in an investigation of the antimicrobial constituents of this Antarctic microorganism, and its structure was determined by spectroscopic methods. Additionally, four known compounds, cyclo-(L-Trp-L-Phe) (2), 4-hydroxyphenylacetic acid (3), (7S)-(+)-hydroxysydonic acid (4) and (7S, 11S)-(+)-12-hydroxysydonic acid (5), were isolated and identified. Biological studies disclosed that compounds 2, 4 and 5 showed moderate inhibitions against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE) as comparing to tigecycline, while compound 1 displayed weak inhibition activities against MRSA and MRSE. 相似文献
5.
The EtOAc and MeOH extracts of the roots of Toddalia asiatica Lam. were investigated for the roots’ chemical constituents. Two new compounds including 2′R-acetoxytoddanol (1) and 8S-10-O-demethylbocconoline (3) as well as 15 known compounds were isolated. Compound 10 showed strong cytotoxicity against KB cells with an IC50 value of 2.60 μg/mL, which is nearly equal to the ellipticine standard, but showed no activity against Vero cells. Alkaloid 3 displayed weak cytotoxicity against the KB cell line with an IC50 value of 21.69 μg/mL. 相似文献
6.
Amr El-Demerdash Céline Moriou Marie-Thérèse Martin Sylvain Petek Ali Al-Mourabit 《Natural product research》2018,32(13):1512-1517
Two new acyclic bis-guanidine alkaloids, unguiculins B-C (2–3), were isolated from a French Polynesian sponge Monanchora n. sp. together with the known compound unguiculin A (1). Their structures were established by spectroscopic data interpretation and comparison with the literature. Unguiculins A-C displayed antiproliferative and cytotoxic efficacy against several human cancer cells with IC50 values in the micromolar range. 相似文献
7.
Chengcheng Zhao Zheming Ying Xiaojun Tao Mingyue Jiang 《Natural product research》2018,32(13):1548-1553
A new lactam alkaloid named oleraciamide D (1), indentified as (5R)-4-(3-methoxy-4-hydroxyphenyl)-5-(4-hydroxyphenyl)-5,6-dihydropyridin-2(1H)-one, together with five known compounds, indole-3-aldehyde (2), portulacatone (3), N-trans-feruloyloctopamine (4), N-trans-feruloyl-3′-O-methyldopamine (5) and N-trans-feruloyltyramine (6) were isolated from Potulaca oleracea L. Among them, indole-3-aldehyde (2) was isolated from the medicine for the first time. The structure of the new alkaloid was elucidated via UHPLC-ESI-Q-TOF/MS, 1D NMR and 2D NMR. The five known compounds were established by comparing the 1H-NMR and 13C NMR with the reported literature. Oleraciamide D (1) showed cytotoxicity against SH-SY5Y cells when concentration at 50 uM by CCK-8 method. 相似文献
8.
AbstractFour new compounds, compounds 1, 2, 4, 6, along with two known compounds 3, 5, were isolated from the methanol extract of the fruiting body of Neoboletus magnificus. The structures of compounds were elucidated by HRMS and NMR spectroscopic methods. The in vitro anti-inflammatory activity of the isolated compounds was evaluated. 相似文献
9.
AbstractA new C19-diterpenoid alkaloid named hemsleyaline (1), along with fourteen known alkaloids (2-15), were isolated from the roots of Aconitum hemsleyanum Pritz. (Ranunculaceae), a herbal medicine in southwest China. Their structures were established on the basis of extensive spectroscopic analyses. Compound 1 showed mild cholinesterase inhibitory effect with IC50 value of 471?±?9?μM. 相似文献
10.
Two new denudatine-type C20-diterpenoid alkaloids, named sinomontanidines A (1) and B (2), were isolated from the roots of Aconitum sinomontanum Nakai. Their structures were elucidated by extensive analysis of 1D, 2D NMR, and MS data. 相似文献