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81.
Two novel hydroquinone derivatives, named guttaquinol A and B (1, 2), together with fifteen known compounds (3–17), were isolated from the roots of Arnebia guttata Bge.. Spectroscopic methods, including NMR, HR-MS, ECD, and data from the literature were used to determine the chemical structures (including the absolute configurations) of the compounds. The chemotaxonomic significance of the isolated compounds was also discussed. 相似文献
82.
Babar Khan Shuangshuang Zhao Zhiyang Wang Yonghao Ye Nasir Ahmed Rajput Wei Yan 《化学与生物多样性》2021,18(4):e2000949
Three new eremophilane sesquiterpenes phomadecalins G−I ( 1 – 3 ) and two new benzene derivatives microdiplzenes A and B ( 12 and 13 ), together with nine known eremophilane sesquiterpenes ( 4 – 11 and 14 ) were isolated from an endophytic fungus, Microdiplodia sp. WGHS5. Their structures were elucidated by the interpretation of HR-ESI-MS and NMR data; meanwhile, the absolute configurations of new compounds were determined on the base of ECD calculations. All compounds were evaluated for the antimicrobial activities and antiproliferative effect on human gastric cancer cell lines (BGC-823). 相似文献
83.
84.
Manuel Medarde Ana B.S. Maya Concepción Pérez-Melero 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):521-540
Synthesis and evaluation of new combretastatin analogues with varied modifications on the bridge and the aromatic rings, have shown that the 2-naphthyl moiety is a good surrogate for the 3-hydroxy-4-methoxyphenyl (B-ring) of combretastatin A-4. Other bicyclic systems, such as 6(7)-quinolyl and 5-indolyl, can replace the B-ring, but they produce less potent analogues in the cytotoxicity and tubulin polymerization inhibition assays. Other modifications are detrimentral for the potency of the studied analogues. The 2-naphthyl combretastatin 53 and the related 6-quinolyl combretastatin 106 analogues are the most potent among the derivatives of this type, whereas 92 and 95 are the most potent among the naphthalene derivatives with a heterocycle in the bridge. Previous and new results in this family of combretastatin analogues are discussed. 相似文献
85.
86.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):545-551
Aminopeptidase N (APN/CD13) over expressed on tumour cells, plays a critical role in tumour invasion, metastasis and tumour angiogenesis. In this article, we described the design, synthesis and preliminary activity studies of novel 3-amino-2-hydroxyl-3-phenylpropanoic acid derivatives as APN inhibitors. The in vitro enzymatic inhibitions on APN from porcine kidney showed that compound 7e had the most potent inhibitory activity against APN with the IC50 value to 1.26?±?0.01 μM, which is better than that of bestatin (IC50?=?2.55?±?0.11 μM). In addition, compound 7e also showed better inhibitory activity against APN on human ovary clear cell carcinoma cell ES-2 than bestatin with the IC50 value to 30.19?±?1.02 μM versus 60.61?±?0.1 μM. Compound 7e could be used as the lead compound in the future for anti-cancer agent research. 相似文献
87.
Fabrice Pagniez Hiam Abdala-Valencia Pascal Marchand Marc Le Borgne Guillaume Le Baut Sylvie Robert-Piessard 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):277-283
Two 3-(α-azolylbenzyl)indoles were evaluated against Leishmania amastigotes. Both compounds proved to be very active against intracellular and axenic amastigotes. The IC50 values of the imidazole derivative, PM17, and the triazole analogue, PM19, against L. mexicana axenic amastigotes, were 4.4 ± 0.1 and 6.4 ± 0.1 μM, respectively. Against intracellular amastigotes, PM17 produced a 66% decrease of leishmanial burden at 1 μM and PM19 had an IC50 of 1.3 μM. In a Balb/c mice model of L. major leishmaniasis, administration of PM17 led to a clear-cut parasite burden reduction: 98.9% in the spleen, 79.0% in the liver and 49.9% in the popliteal node draining the cutaneous lesion. As anticipated, it was brought to the fore that PM17 decreases ergosterol biosynthesis leading to membrane fungal cell alterations. Moreover it was proved that this imidazole antifungal agent induces a parasite burden-correlated decrease in interleukine-4 production both in the splenocyte and the popliteal node of the mouse. 相似文献
88.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):812-817
A series of benzoic acid derivatives 1–10 have been synthesised by two different methods. Compounds 1–6 were synthesised by a facile procedure for esterification using N,N’-dicyclohexylcarbodiimide (DCC) as a coupling agent, methylene chloride as a solvent system and dimethylaminopyridine (DMAP). While 7–10 were synthesised by converting benzoic acid into benzoyl chloride by treating with thionyl chloride in the presence of benzene and performing a further reaction with amine in dried benzene. The structures of all the synthesised derivatives of benzoic acid (1–10) were assigned on the basis of extensive NMR studies. All of them showed inhibitory potential against tyrosinase. Among them, compound 7 was found to be the most potent (1.09 μM) when compared with the standard tyrosinase inhibitors of kojic acid (16.67 μM) and L-mimosine (3.68 μM). Finally in this paper, we have discussed the structure–activity relationships of the synthesised molecules. 相似文献
89.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):1080-1087
In this study, the synthesis and potential enzyme interactions of new Pyrrolo[2,3-d]pyrimidine derivatives along with their inhibitory activity against SFK enzymes such as Fyn, Lyn, Hck, and c-Src were reported. The results indicated that compounds were slightly active of tested SFK enzymes in comparison with PP2 for Fyn, A-419259 for Lyn and CGP77675 for c-Src. Compound N-((2-amino-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)methyl)-4-(3,4-dimethoxyphenyl)butanamide (5) was identified as a non-selective slight inhibitor against Fyn, Lyn and c-Src. However, compounds did not show any inhibitory effects on Hck. Docking studies were performed to analyze the binding mode of compounds against SFKs. The best interaction was obtained between compound 5 and the active site of Fyn and c-Src enzymes in comparison with reference compounds PP2 and CGP77675, respectively. 相似文献
90.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):1162-1170
The α-glucosidase inhibitory activities of bergenin derivatives were evaluated. Bergenin derivatives were synthesized from bergenin which is a characteristic compound of B. ligulata. A new bergenin derivative, 11-O-(3′,4′-dimethoxybenzoyl)-bergenin showed the highest potent inhibitory activity among those of bergenin derivatives. The presence of substituents at 3′,4′-position in bergenin derivatives altered the α-glucosidase inhibitory activity. 11-O-(3′,4′-dimethoxybenzoyl)-bergenin was noncompetitive inhibitor for α-glucosidase. The present study reveals that bergenin derivatives could be classified as a new group of α-glucosidase inhibitors. 相似文献