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1.
Three new biflavonoids, named oliveriflavones A-C (1–3), together with two known flavonoids (quercetin (4) and rutin (5)), were isolated from the endangered plant Cephalotaxus oliveri. The chemical structures of these compounds were elucidated by comprehensive spectroscopic methods including NMR, HRESIMS, IR, UV, and CD spectra. Compounds 1–5 were first isolated from the genus Cephalotaxus. All the compounds were tested for their antioxidant activity. Compounds 4 and 5 showed excellent activity with IC50 values of 0.03 ± 0.06 μM and 0.02 ± 0.10 μM, respectively.  相似文献   
2.
Four thymol derivatives and two phenolic compounds were isolated from the aerial parts of Eupatorium fortunei. The new structures were elucidated to be 7,8,9-trihydroxythymol (1), and 8,10-didehydro-7,9-dihydroxythymol (2) by means of MS and NMR analysis. The known compounds were identified as 8,9,10-trihydroxythymol (3), 10-acetoxy-8,9-dihydroxythymol (4), o-coumaric acid (5) and 4-(2-hydroxyethyl)benzaldehyde (6). Compound 3 showed strongest inhibitory effect on the growth of Microcystis aeruginosa in comparison with CuSO4.  相似文献   
3.
From the branch tissue of Cephalotaxus mannii, the endophytic fungal strain CMM was isolated and determined to belong to the genus Aspergillus according to its internal transcribed spacer (ITS) sequence of rDNA (ITS1-5.8S-ITS2). From the extracts of the fermentation broth of CMM, a new compound, namely 5-O-α-D-glucopyranosyl-5-hydroxymellein (1), was isolated, together with a known compound 4-hydroxymellein (2). Their structures were elucidated on the basis of 1D and 2D NMR data. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 461–462, September-October, 2008.  相似文献   
4.
佩兰挥发性化学成分的固相微萃取研究   总被引:1,自引:0,他引:1  
采用固相微萃取-气相色谱-质谱法分析佩兰中挥发性化学成分,共分离出84个组分,并鉴定了67个组分,用归一化法测定其质量分数,占总挥发性组分峰面积的98.05%。主要成分是对-伞花烃(5.19%)、芳樟醇(3.72%)、β-石竹烯(12.35%)、α-律草烯(13.39%)、α-姜黄烯(2.11%)、(-)-石竹烯氧化物(8.25%)、. /-.-4-乙酰基-1-甲基环己烯(8.91%)。  相似文献   
5.
Phytochemical investigation of Cephalotaxus sinensis has led to the isolation of a new bisabolane sesquiterpenoid (1), a new abietane diterpenoid (2), and 13 known compounds (3–15). Their structures were elucidated by extensive spectroscopic analysis (MS, UV, IR, and NMR).  相似文献   
6.
Three new macrocyclic β‐dihydroagarofuran‐type sesquiterpene pyridine alkaloids, fortuneines A ( 1 ), B ( 2 ), and C ( 3 ), together with the four known alkaloids wilfornine E ( 4 ), aquifoliunine E‐I ( 5 ), euoverrine B ( 6 ), and euojaponine I ( 7 ), were isolated from the aerial parts of Euonymus fortunei. Their structures were elucidated by spectroscopic methods, including HR‐ESI‐MS, 1H‐ and 13C‐NMR, DEPT, 1H,1H‐COSY, HSQC, HMBC, and ROESY. This is the first isolation of the above sesquiterpene pyridine alkaloids from this plant, except for compound 6 .  相似文献   
7.
从骨碎补(Drynaria fortunei)的乙酸乙酯萃取物中分离得到了2个黄酮苷类化合物,结合其理化性质,并通过ESI-MS,IR,1H NMR,13C NMR,1H-1H COSY,HSQC,HMBC等多种波谱学方法进行结构鉴定,鉴定化合物1和2分别为山奈酚-3-O-β-D-6"'-乙酰基-吡喃葡萄糖-(1→4)-α-L-吡喃鼠李糖苷及山奈酚-3-O-β-D-吡喃葡萄糖-(1→4)-α-L-吡喃鼠李糖苷,并对二者的1H NMR 化学位移信号进行了全归属,纠正了文献中C-5和C-9的归属错误.  相似文献   
8.
Cephalotaxine-type alkaloids are the anti-cancer components in twigs, leaves, roots and seeds of Cephalotaxus fortunine. It is very important to use the limited resource by finding an efficient purification technology of the alkaloids. Separation of cephalotaxine-type alkaloids in Cephalotaxus fortunine by step-pH-gradient high-speed counter-current chromatography (step-pH-gradient HSCCC) was studied in this paper. The step-pH-gradient HSCCC was performed on a HSCCC instrument equipped with a 400-mL column, using the upper phase of ethyl acetate–n-hexane–water, with added 0.01% trifluoroacetic acid (TFA) as stationary phase, and the lower phase of ethyl acetate–n-hexane–water, with added 2% NH4OH, 0.2% NH4OH and 0.05% TFA as mobile phase. For each separation, 800 mg of extract of cephalotaxine-type alkaloids was separated to yield 9.3 mg of drupacine, 15.9 mg of wilsonine, 130.4 mg of cephalotaxine, 64.8 mg of epi-wilsonine, 12.8 mg of fortunine and 35.6 mg of acetylcephalotaxine with purities 81.2%, 85.7%, 95.3%, 97.5%, 89.1% and 96.2%, respectively. The recovery of each alkaloid was more than 90%. The structures of the six alkaloids were identified by electrospray ionization mass spectrum (ESI-MS) and 1H and 13C NMR.  相似文献   
9.
A novel compound, named fortunate A, was isolated from the ethanol extract of the stem bark of Cryptomerica fortunei. Its structure was established on the basis of the spectral evidences including 1D and 2D NMR spectrum.  相似文献   
10.
A pair of epimers of highly-oxygenated monoterpenes were isolated from the traditional Chinese medicine Eupatorium fortunei. Their structures were elucidated on the basis of the spectral analysis as (1R*, 2S*, 3R*, 4R*, 6S*)-1, 2, 3, 6-tetrehydroxy-p-menthane (1) and (1S*, 2S*, 3S*, 4R*, 6R*)-1, 2, 3, 6-tetrehydroxy-p-menthane (2).  相似文献   
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