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21.
Uvaria macrophylla is an evergreen tree of the family annonaceae, distributed in Hainan Province, China1. A new flavone, macrophyllol was isolated from the roots of Uvaria macrophylla. In this article we report the structure elucidation of 1.Macrophyllol 1 was isolated as yellow plate crystals, mp: 132-133(C, [(] +4.92 (c 0.06, MeOH). The HREIMS of 1 exhibited [M]+ at m/z 436.1504 corresponding to the molecular formula C25H24O7 (calc.436.1522). The IR spectrum of 1, showed the presenc…  相似文献   
22.
Three new labdane-type diterpenoids, callicapene M3-M5 (1–3) were isolated from the Callicarpa macrophylla Vahl. Their structures were identified by spectroscopic method. The isolated compounds were evaluated for inhibitory activity on NO production in LPS-activated RAW 264.7 macrophage cells by using MTT assays. Compounds 13 showed potent inhibitory activity, with IC50 value of 48.15, 46.31 and 38.72?μM respectively.  相似文献   
23.
Annonaceous acetogenins are considered as the main components with cytotoxicity inthe plants of Annonaceae family. The genus Uvaria is one of the main plants containingAnnonaceous acetogenins, and more than fifty acetogenins have been isolated from eightspecies of the title genus"', however, acetogenins with double bond in the aliphatic chainhas not yet been reported. In this paper we report the structure elucidation of calamistrinE (l), a new acetogenin bearing one double bond besides a tetr…  相似文献   
24.
Abstract

The phytochemical investigation of the leaf extracts of Uvaria hamiltonii (Annonaceae) led to the isolation and identification of ten compounds including a new seco-cyclohexene (1) together with nine known compounds (210). Their structures were elucidated by intensive analysis by spectroscopic methods and comparisons of their spectroscopic data with those of compounds reported in the literature. Compounds 2, 8, and 9 showed potent α-glucosidase inhibitory activity with the IC50 values ranging from 2.6–7.1?µM.  相似文献   
25.
Four new polyoxygenated cyclohexene derivatives, uvarirufone A ( 1 ) and uvarirufols A–C ( 2 – 4 ), along with ten related known compounds, were isolated from the EtOH extract of the aerial parts of Uvaria rufa Bl . Their structures and absolute configurations were determined by in‐depth spectroscopic and spectrometric methods in combination with molecular modeling.  相似文献   
26.
BoFU  QiXiuZHU 《中国化学快报》2002,13(3):249-250
From the roots of Ligularia macrophylla, a bisesquiterpene,ligumacrophyllal was isolated and its structure was elucidated on the basis of spectroscopic methods.  相似文献   
27.
The objective of the current study was to evaluate the phytochemical and pharmacological potential of the Cornus macrophylla. C. macrophylla belongs to the family Cornaceae. It is locally known as khadang and is used for the treatment of different diseases such as analgesic, tonic, diuretic, malaria, inflammation, allergy, infections, cancer, diabetes, and lipid peroxidative. The crude extract and different fractions of C. macrophyll were evaluated by gas chromatography and mass spectroscopy (GC-MS), which identified the most potent bioactive phytochemicals. The antioxidant ability of C. macrophylla was studied by 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and 1,1 diphenyl-2-picryl-hydrazyl (DPPH) methods. The crude and subsequent fractions of the C. macrophylla were also tested against anti-inflammatory enzymes using COX-2 (Cyclooxygenase-2) and 5-LOX (5-lipoxygenase) assays. The molecular docking was carried out using molecular operating environment (MOE) software. The GC-MS study of C. macrophylla confirmed forty-eight compounds in ethyl acetate (Et.AC) fraction and revealed that the Et.AC fraction was the most active fraction. The antioxidant ability of the Et.AC fraction showed an IC50 values of 09.54 μg/mL and 7.8 μg/mL against ABTS and DPPH assay respectively. Among all the fractions of C. macrophylla, Et.AC showed excellent activity against COX-2 and 5-LOX enzyme. The observed IC50 values were 93.35 μg/mL against COX-2 and 75.64 μg/mL for 5-LOX respectively. Molecular docking studies supported these in vitro results and confirmed the anti-inflammatory potential of C. macrophylla. C. macrophylla has promising potential as a source for the development of new drugs against inflammation in the future.  相似文献   
28.
Three new compounds, (5β,9β)‐guaia‐6,10(14)‐dien‐9‐ol (=rel‐(1R,3aS,5R,8aR)‐1,2,3,3a,4,5,6,8a‐octahydro‐1‐methyl‐4‐methylene‐7‐(1‐methylethyl)azulen‐5‐ol; 1 ), 6‐acetyl‐8‐methoxy‐2,3‐dimethylchromen‐4‐one (=6‐acetyl‐8‐methoxy‐2,3‐dimethyl‐4H‐1‐benzopyran‐4‐one; 2 ), and (2S)‐3′‐hydroxy‐5′,7‐dimethoxyflavanone (=(2S)‐2,3‐dihydro‐2‐(3‐hydroxy‐5‐methoxyphenyl)‐7‐methoxy‐4H‐1‐benzopyran‐4‐one; 3 ) were isolated from the roots and rhizomes of Ligularia macrophylla, together with seven known compounds. Their structures and configurations were elucidated by spectroscopic methods, including 2D‐NMR techniques.  相似文献   
29.
<正>A new kaempferol glycoside,named kaempferol 3-O-[6″-O-β-D-glucopyranosyl-6′′′-O-α-L-rhamnopy ranosyl-2′′′′-O-α-L-rhamnopyranosyl]-β-D-glucopyranoside,was isolated from Hydrangea macrophylla(Thunb.) Seringe.Its structure was establishedby spectroscopic techniques including MS,IR,UV,and 2D NMR.  相似文献   
30.
从紫玉盘(Uvaria microcarpa)种子中首次分离得到二个白色蜡状固体, 经光谱分析鉴定: 一个为新的番荔枝内酯-紫玉盘素B(Microcarpacin B), 一个为已知的番荔枝内酯-Rollinicin。  相似文献   
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