共查询到20条相似文献,搜索用时 15 毫秒
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LIU Dan MENG Yan-qiu ZHAO Juan CHEN Li-gong 《高等学校化学研究》2008,24(1):42-46
Ursolic acid was modified at C3 and C28 position to obtain fourteen derivatives including twelve novel compounds, and their chemical structures were characterized by IR, ^1H NMR and MS. Cell growth inhibitory effects of the derivatives against Hela cell were evaluated by MTT assay. All these derivatives were found to have stronger cell growth inhibitory than their parent compound, ursolic acid. The derivatives with a substituted acetyl group at C3 hydroxyl group show better activities than those with an unsubstituted hydroxyl group. 相似文献
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对熊果酸C28位与C3位进行结构修饰得到了24个衍生物, 并利用 1H NMR, 13C NMR, MS及HR-MS对这些化合物进行了结构表征. 进一步通过MTT法, 以内皮细胞HUVEC为主要模型, 研究了24个衍生物抗肿瘤血管生成的活性, 同时以A549, Bel-7402及MCF-7细胞为模型研究了上述衍生物对肿瘤细胞的抑制活性. 研究结果表明, 与熊果酸相比, 化合物5, 9, 12e和14e对HUVEC细胞有较好的选择性, 化合物12a和13h比熊果酸的抗肿瘤血管生成活性略高, 因此通过适当改变熊果酸C28位的结构可以提高其对内皮细胞HUVEC的选择性, 增强抗肿瘤血管生成活性. 本文结果表明, 熊果酸及其衍生物是潜在的具有抗肿瘤血管生成作用的先导化合物, 通过有效的结构优化可能得到新型的抗肿瘤血管生成的化合物. 相似文献
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Synthesis of Novel,Chiral Bicyclo[3.1.0]hex‐2‐ene Amino Acid Derivatives as Useful Synthons in Medicinal Chemistry 下载免费PDF全文
Heinz Stadler 《Helvetica chimica acta》2015,98(9):1189-1201
A short and concise synthesis of novel, chiral bicyclo[3.1.0]hex‐2‐ene amino acid derivatives 13 and 14 has been developed. The key step is a stereo‐ and regioselective allylic amination of exo‐ and endo‐methyl bicyclo[3.1.0]hex‐2‐ene‐6‐carboxylates 8 and 9 , which were prepared from 7,7‐dichlorobicyclo[3.2.0]hept‐2‐en‐6‐one ( 1 ). These amino acid derivatives are useful building blocks in medicinal chemistry and can be prepared as chiral compounds by using either (+)‐ 1 or (?)‐ 1 as starting material. 相似文献
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Anna Wojcicka Edwin Wagner Andrzej Drys Wanda Paulina Nawrocka 《Journal of heterocyclic chemistry》2013,50(4):746-753
New derivatives of 2,7‐naphthyridine‐3‐carboxylic acid were synthesized. We report the hydrolysis, chlorination, alkylation, and amination of the 2,7‐naphthyridine esters 1 , 2 . A series of Schiff's bases 8a , 8b , 8c , 8d , 8e , 8f , 8g , 8h , 8i , 8j , 9a , 9b , 9b' , 9c , 9d , 9e were produced by treating the obtained hydrazides 6 and 7 with aromatic aldehydes. The anticancer activities of the obtained derivatives were examined. Eighteen of the 24 newly synthesized compounds were qualified by the National Cancer Institute NCI (Bethesda, MD, USA) for in vitro screening against 60 different human tumor cell lines. The most active compound 8i was evaluated against a 60‐cell panel at five concentration levels and proved to be most sensitive towards central nervous system cancer (SF‐539), with GI50 = 0.70 µmol, total growth inhibition = 5.41 µmol, and LC50 = 53.7 µmol. 相似文献
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Copper‐Exchanged Tungstophosphoric Acid: An Efficient and Reusable Heteropoly Acid for the Synthesis of 2,3,4,5‐Tetrahydro‐4‐methylidenefuran Derivatives 下载免费PDF全文
Copper‐exchanged tungstophosphoric acid (Cu‐TPA) is found to catalyze efficiently the coupling of propargyl alcohol (prop‐2‐yn‐1‐ol) with (arylmethylidene)malononitriles to afford the corresponding 2,3,4,5‐tetrahydro‐4‐methylidenefuran derivatives in good yields and with high selectivity. The catalyst is recycled and reused for three‐to‐four subsequent runs with a minimal decrease of activity. 相似文献
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Tomoyuki Manaka Shin‐Ichiro Nagayama Wannaporn Desadee Naoki Yajima Takuya Kumamoto Toshiko Watanabe Tsutomu Ishikawa Masatoshi Kawahata Kentaro Yamaguchi 《Helvetica chimica acta》2007,90(1):128-142
Nucleophilic ring‐opening reactions of 3‐aryl‐1‐benzylaziridine‐2‐carboxylates were examined by using O‐nucleophiles and aromatic C‐nucleophiles. The stereospecificity was found to depend on substrates and conditions used. Configuration inversion at C(3) was observed with O‐nucleophiles as a major reaction path in the ring‐opening reactions of aziridines carrying an electron‐poor aromatic moiety, whereas mixtures containing preferentially the syn‐diastereoisomer were generally obtained when electron‐rich aziridines were used (Tables 1–3). In the reactions of electron‐rich aziridines with C‐nucleophiles, SN2 reactions yielding anti‐type products were observed (Table 4). Reductive ring‐opening reaction by catalytic hydrogenation of (+)‐trans‐(2S,3R)‐3‐(1,3‐benzodioxol‐5‐yl)aziridine‐2‐carboxylate (+)‐trans‐ 3c afforded the corresponding α‐amino acid derivative, which was smoothly transformed into (+)‐tert‐butyl [(1R)‐2‐(1,3‐benzodioxol‐5‐yl)‐1‐methylethyl]carbamate((+)‐ 14 ) with high retention of optical purity (Scheme 6). 相似文献
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Synthesis of New C2‐Symmetric Chiral Bisamides from (1S,2S)‐Cyclohexane‐1,2‐dicarboxylic Acid 下载免费PDF全文
A series of new C2‐symmetric (1S,2S)‐cyclohexane‐1,2‐dicarboxamides was synthesized from (1S,2S)‐cyclohexane‐1,2‐dicarbonyl dichloride and N‐benzyl‐substituted aromatic amines, which were prepared from 2‐aminopyridine, 2‐chloroaniline, and 2‐aminophenol via imine formation with benzaldehyde and subsequent reduction with NaBH4. (1S,2S)‐N,N′‐Dibenzyl‐N,N′‐bis[2‐(benzyloxy)phenyl]cyclohexane‐1,2‐dicarboxamide was converted to (1S,2S)‐N,N′‐dibenzyl‐N,N′‐bis(2‐hydroxyphenyl)cyclohexane‐1,2‐dicarboxamide via hydrogenolysis in the presence of Pd(OH)2 on active carbon powder. 相似文献
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Preparation of 4‐butylaniline‐bonded silica gel for the solid‐phase extraction of flavone glycosides 下载免费PDF全文
To extract flavone glycosides efficiently, a new extraction material based on 4‐butylaniline‐bonded silica gel was prepared using a two‐step grafting method including a ring‐opening reaction and synchronous hydrolysis. Preparation of the silica‐based material was easily achieved under mild conditions, and the material was characterized by Fourier transform infrared spectroscopy, elemental analysis, and scanning electron microscopy. The material was used in solid‐phase extraction, and the extraction can be performed in neutral conditions without regard to ionic strength. Selectivity tests of 14 compounds on the extraction cartridge showed that the material has a high affinity to flavone glycosides in contrast to octadecyl silica, and the extraction yields for four flavone glycosides were found to be >93%. Selectivity tests further reveal that the adsorption on its surface is likely attributed to multiple interactions, including hydrophobic interactions, π–π interactions, and hydrogen bonding. To explore the applicability of 4‐butylaniline‐bonded silica gel, naringin and hesperidin from Simotang oral liquid were extracted, and the extraction yields were >90%, which is distinguished from <28% on octadecyl silica cartridge. 相似文献
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A new series of 2,3‐disubstituted quinazolin‐4(3H)‐one derivatives was synthesized by nucleophilic attack at C(2) of the corresponding key starting material 2‐propyl‐4H‐3,1‐benzoxazin‐4‐one (Scheme 2). The reaction proceeded via amidinium salt formation (Scheme 3) rather than via an N‐acylanthranilimide. The structure of the prepared compounds were elucidated by physical and spectral data like FT‐IR, 1H‐NMR, and mass spectroscopy. 相似文献
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Bin Huang Pei‐Gang Huang Shou‐Ri Sheng Qiu‐Ying Wang Lei Guo Shao‐Hua Jiang 《中国化学会会志》2007,54(3):575-578
An efficient liquid‐phase synthesis of 2‐methyl‐2‐aryloxypropanoic acid derivatives with good yields and high purity on soluble polyethylene glycol (PEG) has been developed by treatment of PEG‐bound 2‐bromo‐2‐methylpropanoate with phenoxides in the presence of a catalytic amount of NBu4I and KI, and subsequent cleavage from the PEG. 相似文献
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Synthesis of (S)-2-Ethoxy-3-Phenylpropanoic Acid Derivatives and Their Insulin-Sensitizing Activity 总被引:1,自引:0,他引:1
A series of (S)-2-ethoxy-3-phenylpropanoic acid derivatives were synthesized and their insulin-sensitizing activities were evaluated in 3T3-L1 cells. Compounds 1b, 1d, 1e and 1f exhibited more potent insulin-sensitizing activity than rosiglitazone. 相似文献
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Xiang Li Xiaojin Zhang Haopeng Sun Lei Zhang Yuan Gao Jinxin Wang Qinglong Guo Qidong You 《中国化学》2012,30(5):1083-1091
Gambogic acid (GA, 1 ), the most prominent representative of Garcinia natural products, has been reported to be a promising anti‐tumor agent. In order to further explore the structure‐activity relationship of GA and discover novel GA derivatives as anti‐tumor agents, 17 novel C‐37 modified derivatives of GA were synthesized and evaluated for their in vitro anti‐tumor activities against A549, HCT‐116, BGC‐823, HepG2 and MCF‐7 cancer cell lines. Among them, 11 compounds were found to be more potent than GA against some cancer cell lines. Notably, compound 8 was almost 5–10 folds more active than GA against A549 and BGC‐823 cell lines with the IC50 values of 0.12 µmol·L?1 and 0.57 µmol·L?1, respectively. Chemical modification at C‐37 position of GA by introducing of hydrophilic amines could lead to increased activity and improved drug‐like properties. These findings will enhance our understanding of the structure‐activity relationship (SAR) of GA and lead to the discovery of novel GA derivatives as potential anti‐tumor agents. 相似文献
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Naser Foroughifar Akbar Mobinikhaledi Sattar Ebrahimi Mohammad Ali Bodaghi Fard Hassan Moghanian 《中国化学会会志》2009,56(5):1043-1047
Some new and optically active 1,2,4‐triazolo thiadiazoles bearing N‐phthaloyl‐l ‐amino acids were synthesized by reaction of 4‐amino‐5‐(3‐ or 4‐)pyridyl‐3‐mercapto‐(4H)‐1,2,4‐triazoles with N‐phthaloyl‐l ‐amino acids in the presence of phosphorus oxychloride. All the newly synthesized compounds were confirmed by IR, 1H NMR, 13C NMR and elemental analysis. 相似文献
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Magnetic graphene oxide functionalized with sulfonic acid (Fe3O4‐GO‐SO3H) was used as a new recyclable nanocatalyst for one‐pot synthesis of N‐aryl‐2‐amino‐1,6‐naphthyridine derivatives under solvent free conditions. The catalyst could be easily recovered from the reaction mixture by an external magnet and reused without significant decrease in activity even after 4 runs. This nanocatalyst exhibited better activities to other commercially available sulfonic acid catalysts. 相似文献
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Jui‐Chi Tsai Sie‐Rong Li Liang‐Yeu Chen Po‐Yuan Chen Jia‐Ying Joung Chung‐Jung Shu Yu‐Fuan Lo Chun‐Nan Lin Eng‐Chi Wang 《中国化学会会志》2008,55(6):1317-1321
In this paper, the synthesis of 3‐aryl‐2,5‐dihydro‐1‐benzoxepines is described. While the reaction was started from phenol and based on the sequential reactions such as Claisen rearrangement, O‐alkylation, Wittig reaction, and ring‐closing metathesis (RCM), a series of new 3‐aryl‐1‐benzoxepines were prepared in good overall yields. 相似文献