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1.
Three new compounds (2R)‐2‐hydroxy‐N‐[(2S,3S,4R,10E)‐1,3,4‐trihydroxyicos‐10‐en‐2‐yl]docosanamide ( 1 ), (2R,3R)‐2,3‐dihydroxy‐N‐[(2S,3S,4R,10E)‐1,3,4‐trihydroxyicos‐10‐en‐2‐yl]docosanamide ( 2 ), N‐(2‐phenylethyl)tetracosanamide ( 3 ), together with a known ceramide, (2R)‐N‐[(2S,3S,4R,8E)‐1‐(β‐D ‐Glucopyranosyloxy)‐3,4‐dihydroxyoctadec‐8‐en‐2‐yl]‐2‐hydroxyhexadecanamide ( 4 ), were isolated from acetone extract of flower disc of Helianthus annuus L. The structures were identified on the basis of chemical and spectroscopic methods. 相似文献
2.
Two new cerebrosides, (2R)‐N‐{(1S,2S,3R,8E)‐1‐[(β‐D ‐glucopyranosyloxy)methyl]‐2,3‐dihydroxyheptadec‐8‐en‐1‐yl}‐2‐hydroxyhexadecanamide ( 1 ) and (2R)‐N‐{(1S,2R,8E)‐1‐[(β‐D ‐glucopyranosyloxy)methyl]‐2‐hydroxyheptadec‐8‐en‐1‐yl}‐2‐hydroxyhexadecanamide ( 2 ), were isolated from the aerial parts of Tithonia diversifolia (Hemsl .) A. Gray. Their structures were determined on the basis of spectroscopic analysis (IR, HR‐ESI‐MS, and 1D‐, and 2D‐NMR). 相似文献
3.
Shu‐Min Yang Shao‐Hua Wu Xiang‐Dong Qin Xiao‐Dong Luo Da‐Gang Wu 《Helvetica chimica acta》2004,87(5):1279-1286
From the twigs of Amoora stellato‐squamosa, five new neoclerodane diterpenes have been isolated and characterized, methyl (13E)‐2‐oxoneocleroda‐3,13‐dien‐15‐oate (=methyl (2E)‐3‐methyl‐5‐[(1S,2R,4aR,8aR)‐1,2,3,4,4a,7,8,8a‐octahydro‐1,2,4a,5‐tetramethyl‐7‐oxo‐naphthalen‐1‐yl]pent‐2‐enoate; 1 ), (13E)‐2‐oxoneocleroda‐3,13‐dien‐15‐ol (=(4aR,7R,8S,8aR)‐1,2,4a,5,6,7,8,8a‐octahydro‐8‐[(E)‐5‐hydroxy‐3‐methylpent‐3‐enyl]‐4,4a,7,8‐tetramethylnaphthalen‐2(1H)‐one; 2 ), (3α,4β,13E)‐neoclerod‐13‐ene‐3,4,15‐triol (=(1R,2R,4aR, 5S,6R,8aR)‐decahydro‐5‐[(E)‐5‐hydroxy‐3‐methylpent‐3‐enyl]‐1,5,6,8a‐tetramethylnaphthalene‐1,2‐diol; 3 ), (3α,4β,13E)‐4‐ethoxyneoclerod‐13‐ene‐3,15‐diol (=(1R,2R,4aR,5S,6R,8aR)‐1‐ethoxydecahydro‐5‐[(E)‐5‐hydroxy‐3‐methylpent‐3‐enyl]‐1,5,6,8a‐tetramethylnaphthalen‐2‐ol; 4 ), and (3α,4β,14RS)‐neoclerod‐13(16)‐ ene‐3,4,14,15‐tetrol (=(1R,2R,4aR,5S,6R,8aR)‐decahydro‐5‐[3‐(1,2‐dihydroxyethyl)but‐3‐enyl]‐1,5,6,8a‐tetramethylnaphthalene‐1,2‐diol; 5 ), together with two known compounds, (13E)‐neocleroda‐3,13‐diene‐15,18‐diol ( 6 ) and (13S)‐2‐oxoneocleroda‐3,14‐dien‐13‐ol ( 7 ). 相似文献
4.
A new ceramide and its glycoside were isolated from the flower of Albizia julibrissin. Their structures were established as(2S,3S,4R,8E)-2-[(2'R)-hydroxyhexadecanoylamino]-8-tetra-cosene-1,3,4-triol (Ⅰ) and 1-O-β-D-glucopyranosyl-(2S,3S,4R,8E)-2-[(2'R)-hydroxy-hexade-canoylamino]-8-tetracosene-1,3,4-triol (H) on the basis of chemical and spectroscopic studies. 相似文献
5.
An efficient and practical route to synthesize (2S,3S,4R)-2-azido-3,4-O-isopropyllidene-1,3,4-octadecanetriol from D-galactose in 18% overall yield was described, which required ten steps of reactions and only four times column chromatography purification. 相似文献
6.
M.Iqbal Choudhary Irfan Baig M. Nur‐e‐Alam S. Shahzad‐ul‐Hussan Purev
ndognii M. Bunderya Z. Oyun Atta‐ur‐Rahman 《Helvetica chimica acta》2001,84(8):2409-2416
The four new and four known sesquiterpenoid derivatives 1 – 4 and 5 – 8 , respectively, were isolated from the air‐dried roots of Ferula mongolica. The structures of these compounds were determined by spectroscopic methods and found to be rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐3,4‐dihydro‐3,8‐dihydroxy‐2‐methyl‐2H,5H‐pyrano[2,3‐b][1]benzopyran‐5‐one ( 1 ), rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐2,3‐dihydro‐7‐hydroxy‐2,3‐dimethyl‐4H‐furo[2,3‐b][1]benzopyran‐4‐one ( 2 ), rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐2,3‐dihydro‐7‐hydroxy‐2,3‐dimethyl‐4H‐furo[3,2‐c][1]benzopyran‐4‐one ( 3 ), rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐2,3‐dihydro‐7‐methoxy‐2,3‐dimethyl‐4H‐furo[3,2‐c][1]benzopyran‐4‐one ( 4 ), (4E,8E)‐1‐(2‐hydroxy‐4‐methoxyphenyl)‐5,9,13‐trimethyltetradeca‐4,8,12‐trien‐1‐one ( 5 ), the rel‐(2R,3S) diastereoisomer 6 of 2 , the rel‐(2R,3S) diastereoisomer 7 of 4 , and (4E,8E)‐1‐(2,4‐dihydroxyphenyl)‐5,9,13‐trimethyltetradeca‐4,8,12‐trien‐1‐one ( 8 ). These compounds were tested as inhibitors against the enzyme α‐glucosidase. The compounds 1 – 6 and 8 exhibited significant inhibitory activity and, therefore, represent a new class of α‐glucosidase inhibitors. 相似文献
7.
Two new 7‐dehydrobrefeldin A acids, (2E,4R*)‐4‐hydroxy‐4‐{(1R*,2S*)‐4‐oxo‐2‐[(1E)‐6‐oxohept‐1‐en‐1‐yl]cyclopentyl}but‐2‐enoic acid ( 3 ) and (2E,4R*)‐4‐hydroxy‐4‐{(1R*,2S*)‐2‐[(1E,6S*)‐6‐hydroxyhept‐1‐en‐1‐yl]‐4‐oxocyclopentyl}but‐2‐enoic acid ( 4 ), were isolated from the endophytic fungal strain Cylindrocarpon obtusisporum (Cooke & Harkness ) Wollenw . of Trewia nudiflora, together with two known compounds, 7‐dehydrobrefeldin A ( 2 ) and brefeldin A ( 1 ). Their structures were determined on the basis of extensive 1D‐ and 2D‐NMR‐spectral analysis. 相似文献
8.
Sheng‐Xiang Yang Jin‐Ming Gao Jian‐Chun Qin Lin Zhou Ming‐Hua Chiu Lei Wang 《Helvetica chimica acta》2007,90(8):1477-1481
A new triterpene, (3β,12β)‐taraxast‐20(30)‐ene‐3,12‐diol (=(3β,12β,18α,19α)‐urs‐20(30)‐ene‐3,12‐diol; 1 ), together with the known compounds ursolic acid, α‐amyrin, β‐amyrin, (2α,3β)‐2,3‐dihydroxyursa‐5,12‐dien‐28‐oic acid, (2α,3β)‐2,3,23‐trihydroxyurs‐12‐en‐28‐oic acid, (2S,3S,4R,8Z)‐1‐O‐(β‐D ‐glucopyranosyl)‐2‐{[(2R)‐2‐hydroxydocosanoyl]amino}octadec‐8‐ene‐1,3,4‐triol, and (2S,3S,4R,8Z)‐1‐O‐(β‐D ‐glucopyranosyl)‐2‐[(palmitoyl)amino]octadec‐8‐ene‐1,3,4‐triol, and quercetin 3‐(β‐D ‐glucopyranoside) were isolated from the leaves of Craibiodendron yunnanense. Their structures were established on the basis of spectral evidence. The last four compounds were identified for the first time in this plant. 相似文献
9.
Ming‐Jen Cheng Bolleddula Jayaprakasam Tsutomu Ishikawa Hiroko Seki Ian‐Lih Tsai Jeh‐Jeng Wang Ih‐Sheng Chen 《Helvetica chimica acta》2002,85(7):1909-1914
Five new compounds, including a novel lactone, machilactone (=rel‐(2R,3aR,6E,6aS)‐2‐heptadecyl‐3a‐methyl‐6‐octadecylidene‐6,6a‐dihydrofuro[2,3‐d][1,3]dioxol‐5(3aH)‐one; 1 ), a new sesquiterpene, 3,4‐dihydroxy‐β‐bisabolol (=rel‐(1R,2S,4R)‐1‐[(1R)‐1,5‐dimethylhex‐4‐enyl]‐1‐methylcyclohexane‐1,2,4‐triol; 2 ), a new secobutyrolactone, methyl (2E)‐2‐(1‐hydroxy‐2‐oxopropyl)eicos‐2‐enoate ( 3 ), two new butyrolactones, machicolide A ( 4 ) and machicolide B ( 5 ) (=3E,4R,5R)‐ and (3Z,4R,5R)‐4,5‐dihydro‐4‐hydroxy‐5‐methoxy‐5‐methyl‐3‐octadecylidenefuran‐2(3H)‐one, resp.) as a mixture, together with known caryophyllene oxide (=4,12,12‐trimethyl‐9‐methylene‐5‐oxatricyclo[8.2.0.04,6]dodecane), hexacosane, tetracosanoic acid, isomahubanolide‐23 (=(3E,4R)‐4,5‐dihydro‐4‐hydroxy‐5‐methylidene‐3‐octadecylidenefuran‐2(3H)‐one), and β‐bisabolol (=(1S)‐1‐[(1S)‐1,5‐dimethylhex‐4‐enyl]‐4‐methylcyclohex‐3‐en‐1‐ol) were isolated from the stem wood of Machilus zuihoensis. The structures of these compounds were established by spectroscopic studies. The eicos‐2‐enoate ( 3 ) and β‐bisabolol exhibited marginal cytotoxicity against NUGC and HONE‐1 cancer cell lines in vitro. 相似文献
10.
Frdric Carrel Sylvain Giraud Olivier Spertini Pierre Vogel 《Helvetica chimica acta》2004,87(5):1048-1070
Wittig olefination of (2S,3R,5S,6R)‐5‐(acetyloxy)‐tetrahydro‐6‐[(methoxymethoxy)methyl]‐3‐(phenylthio)‐ 2H‐pyran‐2‐acetaldehyde ((+)‐ 10 ) with {2‐[(2S,3R,4R,5R,6S)‐tetrahydro‐3,4,5‐tris(methoxymethoxy)‐6‐methyl‐ 2H‐pyran‐2‐yl]ethyl}triphenylphosphonium iodide ((?)‐ 11 ) gave a (Z)‐alkene derivative (+)‐ 12 that was converted into (αR,2R,3S,4R,5R,6S)‐tetrahydro‐α,3‐dihydroxy‐2‐(hydroxymethyl)‐5‐(phenylthio)‐6‐{(2Z)‐4‐[(2S,3S,4R,5S,6S)‐tetrahydro‐3,4,5‐trihydroxy‐6‐methyl‐2H‐pyran‐2‐yl]but‐2‐enyl}2H‐pyran‐4‐acetic acid ( 8 ), (αR,2R,3S,4R,6S)‐tetrahydro‐α,3‐dihydroxy‐2‐(hydroxymethyl)‐6‐{4‐[(2S,3S,4R,5S,6S)‐tetrahydro‐3,4,5‐trihydroxy‐6‐methyl‐2H‐pyran‐2‐yl]butyl}‐2H‐pyran‐4‐acetic acid ( 9 ), and simpler analogues without the hydroxyacetic side chain such as (2S,3S,4R,5S,6S)‐tetrahydro‐6‐methyl‐2‐{(2Z)‐4‐[(2S,3R,5S,6R)‐tetrahydro‐5‐hydroxy‐6‐(hydroxymethyl)‐3‐(phenylthio)‐2H‐pyran‐2‐yl]but‐2‐enyl}‐2H‐pyran‐3,4,5‐triol ( 30 ), (2S,3S,4R,5S,6S)‐tetrahydro‐6‐methyl‐2‐{[(2S,5S,6R)‐tetrahydro‐5‐hydroxy‐6‐(hydroxymethyl)‐2H‐pyran‐2‐yl]butyl}‐2H‐pyran‐3,4,5‐ triol ((?)‐ 41 ) and (2S,3S,4R,5S,6S)‐tetrahydro‐6‐methyl‐2‐{(2Z/E))‐4‐[(2R,5S,6R)‐tetrahydro‐5‐hydroxy‐6‐(hydroxymethyl)‐2H‐pyran‐2‐yl]but‐2‐enyl}‐2H‐pyran‐3,4,5‐triol ( 43 ). The key intermediates (+)‐ 10 and (?)‐ 11 were derived from isolevoglucosenone and from L ‐fucose, respectively. The following IC50 values were measured in a ELISA test for the affinities of sialyl Lewis x tetrasaccharide, 8, 9, 30 , (?)‐ 41 , and 43 toward P‐selectin: 0.7, 2.5–2.8, 7.3–8.0, 5.3–5.9, 5.0–5.2, and 3.4–4.1 mM , respectively. 相似文献
11.
Two new diarylheptanoids, katsumains A ( 1 ) and B ( 2 ), and one new kavalactone, katsumadain ( 3 ), together with the three known compounds (4E,6E)‐1,7‐diphenylhepta‐4,6‐dien‐3‐one ( 4 ), (5R,6E)‐1,7‐diphenyl‐5‐hydroxyhept‐6‐en‐3‐one ( 5 ), and cardamonin ( 6 ), were isolated from the seeds of Alpinia katsumadai Hayata . Their structures were elucidated mainly by spectroscopic methods (1D‐ and 2D‐NMR) and by mass spectrometry (HR‐ESI‐MS). Besides, the erroneous nomenclatures for (+)‐linderatin and (+)‐neolinderatin as given in [10] [11] were corrected to be 2′,4′,6′‐trihydroxy‐3′‐[(3R,4R)‐4‐isopropyl‐1‐methylcyclohex‐1‐en‐3‐yl]dihydrochalcone for (+)‐linderatin and 2′,4′,6′‐trihydroxy‐3′,5′‐bis[(3R,4R)‐4‐isopropyl‐1‐methylcyclohex‐1‐en‐3‐yl]dihydrochalcone for (+)‐neolinderatin, respectively. 相似文献
12.
Du‐Qiang Luo Yuan Gao Xiao‐Long Yang Jian‐Guo Tang Li‐Yan Zhao Ji‐Kai Liu 《Helvetica chimica acta》2007,90(6):1112-1116
Two new highly oxidized humulane sesquiterpenes, mitissimols F ( 1 ) and G ( 2 ), were isolated from the fruiting bodies of Lactarius mitissimus. Their structures were elucidated by using extensive spectroscopic techniques including 1D‐ and 2D‐NMR experiments. The absolute configuration of mitissimol F ( 1 ) was determined by 1H‐NMR resolution of its diastereoisomeric α‐methoxy‐α‐(trifluoromethyl)benzeneacetates (MTPA). It was shown to be (1S,3E,6S,8R,9R,10S,11R)‐8,9 : 10,11‐diepoxy‐1,6‐dihydroxyhumul‐3‐en‐5‐one (=(1S,2R,4R,6S,8E,11S,12R)‐6,11‐dihydroxy‐1,6,10,10‐tetramethyl‐3,13‐dioxatricyclo[10.1.0.02,4]tridec‐8‐en‐7‐one). 相似文献
13.
Zhiping Wu Yu Chen Xu Feng Bing Xia Ming Wang Yunfa Dong 《Chemistry of Natural Compounds》2009,45(6):829-833
Two new ceramides were isolated from the bulbs of Zephyranthes candida. Their structures were established as (2S,3S,4R,13E)-1,3,4-trihydroxy-2-[(2′R)-2′-hydroxytetracosanoylamino]-13-octadecene, named zephyranamide A (1) and (2S,3S,4R)-1,3,4-trihydroxy-2-octacosanoylaminohexadecene, named zephyranamide B (2). The structures of the new compounds were elucidated by spectral techniques including 1H NMR, 13C NMR, as well as HSQC, HMBC, DEPT, and COSY. 相似文献
14.
Paecilomycines A and B,Novel Diterpenoids,Isolated from Insect‐Pathogenic Fungi Paecilomyces sp. ACCC 37762
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Kun Zhou Xiao‐Ling Zhao Li‐Ping Han Meng‐Meng Cao Chuan Chen Bao‐Zhong Shi Du‐Qiang Luo 《Helvetica chimica acta》2015,98(5):642-649
Two new diterpenoids, named paecilomycine A ( 1 ) and paecilomycine B ( 2 ), including a novel skeleton with a five‐membered lactone ring, together with three known labdane diterpenoids, rel‐(1R,3S,4aS,5R,8aS)‐5‐[(3E)‐4‐carboxy‐3‐methylbut‐3‐en‐1‐yl]decahydro‐3‐hydroxy‐1,4a‐dimethyl‐6‐methylidenenaphthalene‐1‐carboxylic acid ( 3 ), botryosphaerin E ( 4 ), and agathic acid ( 5 ), were isolated from solid culture of the insect pathogenic fungi strain Paecilomyces sp. The structures of all compounds were established on the basis of comprehensive spectroscopic studies. The relative configurations of 1 and 2 were determined by single‐crystal X‐ray diffraction analyses. 相似文献
15.
Guang‐Wen Zhang Xiang‐Quan Ma Cui‐Xian Zhang Jing‐Yu Su Wen‐Cai Ye Xiao‐Qi Zhang Xin‐Sheng Yao Long‐Mei Zeng 《Helvetica chimica acta》2005,88(4):885-890
A new 4‐sulfated ceramide, ircisulfamide (=N‐[(1S*,2S*,3R*)‐2‐hydroxy‐1‐(hydroxymethyl)‐3‐(sulfooxy)heptadecyl]hexadecanamide; 1 ), and a new glycosphingolipid, ircicerebroside (=(2R*)‐N‐{(1S*,2R*,3E,7E)‐1‐[(β‐D ‐glucopyranosyloxy)methyl]‐2‐hydroxy‐8‐methylheptadeca‐3,7‐dienyl}‐2‐hydroxyeicosanamide; 2 ), were isolated from the aqueous EtOH extract of the marine sponge Ircinia fasciculata (Pallas ). The structures of the new compounds were elucidated on the basis of spectroscopic analysis and by means of chemical methods. 相似文献
16.
The reaction of 1‐(trimethylsilyloxy)cyclopentene ( 9 ) with (±)‐1,3,5‐triisopropyl‐2‐(1‐(RS)‐{[(1E)‐2‐methylpenta‐1,3‐dienyl]oxy}ethyl)benzene ((±)‐ 4a ) in SO2/CH2Cl2 containing (CF3SO2)2NH, followed by treatment with Bu4NF and MeI gave a 3.0 : 1 mixture of (±)‐(2RS)‐2{(1RS,2Z,4SR)‐2‐methyl‐4‐(methylsulfonyl)‐1‐[(RS)‐1‐(2,4,6‐triisopropylphenyl)ethoxy]pent‐2‐en‐1‐yl}cyclopentanone ((±)‐ 10 ) and (±)‐(2RS)‐2‐{(1RS,2Z)‐2‐methyl‐4‐[(SR)‐methylsulfonyl]‐1‐[(SR)‐1‐(2,4,6‐triisopropylphenyl)ethoxy]pent‐2‐en‐1‐yl}cyclopentanone ((±)‐ 11 ). Similarly, enantiomerically pure dienyl ether (−)‐(1S)‐ 4a reacted with 1‐(trimethylsilyloxy)cyclohexene ( 12 ) to give a 14.1 : 1 mixture of (−)‐(2S)‐2‐{(1S,2Z,4R)‐2‐methyl‐4‐(methylsulfonyl)‐1‐[(S)‐1‐(2,4,6‐triisopropylphenyl)ethoxy]pent‐2‐enyl}cyclohexanone ((−)‐ 13a ) and its diastereoisomer 14a with (1S,2R,4R) or (1R,2S,4S) configuration. Structures of (±)‐ 10 , (±)‐ 11 , and (−)‐ 13a were established by single‐crystal X‐ray crystallography. Poor diastereoselectivities were observed with the (E,E)‐2‐methylpenta‐1,3‐diene‐1‐ylethers (+)‐ 4b and (−)‐ 4c bearing ( 1 S )‐1‐phenylethyl and (1S)‐1‐(pentafluorophenyl)ethyl groups instead of the Greene's auxiliary ((1S)‐(2,4,6‐triisopropylphenyl)ethyl group). The results demonstrate that high α/β‐syn and asymmetric induction (due to the chiral auxiliary) can be obtained in the four‐component syntheses of the β‐alkoxy ketones. The method generates enantiomerically pure polyfunctional methyl sulfones bearing three chiral centers on C‐atoms and one (Z)‐alkene moiety. 相似文献
17.
MichaelJ. Dobner ErnstP. Ellmerer Stefan Schwaiger Odonchimeg Batsugkh Samdan Narantuya Michaela Stütz Hermann Stuppner 《Helvetica chimica acta》2003,86(3):733-738
Three new compounds, including a benzofuran, 1‐{(2R*,3S*)‐3‐(β‐D ‐glucopyranosyloxy)‐2,3‐dihydro‐2‐[1‐(hydroxymethyl)vinyl]‐1‐benzofuran‐5‐yl}ethanone ( 1 ), a lignan, [(2S,3R,4R)‐4‐(3,4‐dimethoxybenzyl)‐2‐(3,4‐dimethoxyphenyl)tetrahydrofuran‐3‐yl]methyl (2E)‐2‐methylbut‐2‐enoate ( 2 ), and a silphiperfolene‐type sesquiterpene, [(1S,2Z,3aS,5aS,6R,8aR)‐1,3a,4,5,5a,6,7,8‐octahydro‐1,3a,6‐trimethylcyclopenta[c]pentalen‐2‐yl]methyl acetate ( 3 ), together with the known coumarins obliquin ( 4 ) and its 5‐methoxy derivative 5 were isolated from the roots of Leontopodium alpinum. Another known coumarin derivative, 5‐hydroxyobliquin ( 6 ), was isolated from the roots of L. leontopodioides. The structures of these compounds were established by spectroscopic studies. 相似文献
18.
Guy‐Bertrand Djigoue Michel Simard Lucie‐Carolle Kenmogne Donald Poirier 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(6):o231-o234
The title compounds, (3R,5S,5′R,8R,9S,10S,13S,14S)‐10,13‐dimethyl‐5′‐(2‐methylpropyl)tetradecahydro‐6′H‐spiro[cyclopenta[a]phenanthrene‐3,2′‐[1,4]oxazinane]‐6′,17(2H)‐dione, C26H41NO3, (I), and methyl (2R)‐2‐[(3R,5S,8R,9S,10S,13S,14S)‐10,13‐dimethyl‐2′,17‐dioxohexadecahydro‐3′H‐spiro[cyclopenta[a]phenanthrene‐3,5′‐[1,3]oxazolidin‐3′‐yl]]‐4‐methylpentanoate, C28H43NO5, (II), possess the typical steroid shape (A–D rings), but they differ in their extra E ring. The azalactone E ring in (I) shows a half‐chair conformation, while the carbamate E ring of (II) is planar. The orientation of the E‐ring substituent is clearly established and allows a rationalization of the biological results obtained with such androsterone derivatives. 相似文献
19.
Yogesh P. Bharitkar N.S. Apoorva Poduri Anirban Ash Prakas R. Maulik Nirup B. Mondal 《Natural product research》2015,29(3):253-261
Aervalanata possesses various useful medicinal and pharmaceutical activities. Phytochemical investigation of the plant has now led to the isolation of a new 2α,3α,15,16,19-pentahydroxy pimar-8(14)-ene diterpenoid (1) together with 12 other known compounds identified as β-sitosterol (2), β-sitosterol-3-O-β-D-glucoside (3), canthin-6-one (4), 10-hydroxycanthin-6-one (aervine, 5), 10-methoxycanthin-6-one (methylaervine, 6), β-carboline-1-propionic acid (7), 1-O-β-D-glucopyranosyl-(2S,3R,8E)-2-[(2′R)-2-hydroxylpalmitoylamino]-8-octadecene-1,3-diol (8), 1-O-(β-D-glucopyranosyl)-(2S,3S,4R,8Z)-2-[(2′R)-2′-hydroxytetracosanoylamino]-8(Z)-octadene-1,3,4-triol (9), (2S,3S,4R,10E)-2-[(2′R)-2′-hydroxytetracosanoylamino]-10-octadecene-1,3,4-triol (10), 6′-O-(4″-hydroxy-trans-cinnamoyl)-kaempferol-3-O-β-D-glucopyranoside (tribuloside, 11), 3-cinnamoyltribuloside (12) and sulfonoquinovosyldiacylglyceride (13). Among these, six compounds (8–13) are reported for the first time from this plant. Cytotoxicity evaluation of the compounds against five cancer cell lines (CHO, HepG2, HeLa, A-431 and MCF-7) shows promising IC50 values for compounds 4, 6 and 12. 相似文献
20.
Two new polar lignans, i.e., squadinorlignoside (= 4‐[(1E)‐1‐(hydroxymethyl)‐3‐(4‐hydroxyphenyl)prop‐1‐en‐1‐yl]phenyl β‐D ‐glucopyranoside; 1 ) and (6R,7R,8S)‐7a‐[(β‐D ‐glucopyranosyl)oxy]‐1‐methoxyisolariciresinol ( 2 ) were isolated from the stems of Annona squamosa, together with eight known lignans and five known neolignans (compounds 3 – 15 ; Fig. 1). All of these constituents are reported for the first time from the genus Annona. The structures, absolute configurations, and selected conformational aspects of the new compounds were elucidated spectroscopically. Compound 1 is the first example of a 7,9′‐dinorlignan natural product. 相似文献