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71.
Fidelia Ijeoma Uche James McCullagh Timothy W.D. Claridge Alan Richardson Wen-Wu Li 《Bioorganic & medicinal chemistry letters》2018,28(9):1652-1656
Our previous studies demonstrated that cycleanine, a macrocyclic bisbenzylisoquinoline (BBIQ) alkaloid, showed potent anti-ovarian cancer activity via apoptosis induction. Here, we synthesized two novel (aminoalkyl)cycleanine analogues (2 and 3) through a simple and efficient two-step reaction starting from cycleanine isolated from Triclisia subcordata Oliv. These analogues showed greater potency than the unmodified cycleanine in three human ovarian cancer cell lines. Both 2 and 3 induced apoptosis in ovarian cancer cells by activations of caspases 3/7, cleavage of PARP, increase in subG1 cell cycle phase and in the percentage of apoptotic cells. Further confocal fluorescence microscopy analysis confirmed the cellular uptake of alkaloids in ovarian cancer cells by using the unique (alkynyl)cycleanine (3) via click chemistry reaction. Our results suggest that cycleanine could be a hit compound for the future development in attacking ovarian cancer. 相似文献
72.
Chada Raji Reddy Amol Gorgile Tukaram Siddique Z. Mohammed Uredi Dilipkumar Bathini Nagendra Babu Sumana Chakravarty Dwaipayan Bhattacharya Pranav C. Joshi René Grée 《Bioorganic & medicinal chemistry letters》2018,28(4):673-676
Longanlactone analogues were synthesized using a route featuring Friedel-Crafts acylation, Sonogashira coupling and 1,3-dipolar cycloaddition reactions. Structure–activity relationships were investigated for neurotrophic activity. Compound 6 was found to have the most potent neurotrophic activity among all the synthesized analogues in Neuro2a cells as evidenced by a battery of in vitro/cell based assays for assessment of neurogenic and potential neurotrophic activity including neurite outgrowth assay and real time PCR for popular markers of augmented neurotrophic activity. Compound 6 might serve as a template for further development of highly effective neurotrophic molecules. 相似文献
73.
Binding affinity and in vitro cytotoxicity of harmaline targeting different motifs of nucleic acids: An ultimate drug designing approach
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Paromita Bhattacharjee Tapas Ghosh Sarita Sarkar Prateek Pandya Kakali Bhadra 《Journal of molecular recognition : JMR》2018,31(4)
The work focuses towards interaction of harmaline, with nucleic acids of different motifs by multispectroscopic and calorimetric techniques. Findings of this study suggest that binding constant varied in the order single‐stranded (ss) poly(A) > double‐stranded calf thymus (CT) DNA > double‐stranded poly(G)·poly(C) > clover leaf tRNAPhe. Prominent structural changes of ss poly(A), CT DNA, and poly(G)· poly(C) with concomitant induction of optical activity in the bound achiral alkaloid molecule was observed, while with tRNAPhe, very weak induced circular dichroism perturbation was seen. The interaction was predominantly exothermic, enthalpy driven, and entropy favored with CT DNA and poly(G)·poly(C), while it was entropy driven with poly(A) and tRNAPhe. Intercalated state of harmaline inside poly(A), CT DNA, and poly(G)·poly(C) was shown by viscometry, ferrocyanide quenching, and molecular docking. All these findings unequivocally pointed out preference of harmaline towards ss poly(A) inducing self‐structure formation. Furthermore, harmaline administration caused a significant decrease in proliferation of HeLa and HepG2 cells with GI50 of 28μM and 11.2μM, respectively. Nucleic acid fragmentation, cellular ultramorphological changes, decreased mitochondrial membrane potential, upregulation of p53 and caspase 3, generation of reactive oxygen species, and a significant increase in the G2/M population made HepG2 more prone to apoptosis than are HeLa cells. 相似文献
74.
A. Giri S. Banerjee P. S. Ahuja C. C. Giri 《In vitro cellular & developmental biology. Plant》1997,33(4):280-284
Summary A method for the production of hairy roots of Aconitum heterophyllum wall. is reported for the first time. Embryogenic callus cultures were successfully transformed using Agrobacterium rhizogenes strains viz. LBA 9402, LBA 9360, and A4 for the induction of hairy roots. The transgenic nature of hairy roots was confirmed
by mannopine assay using paper electrophoresis. Best growth of transformed roots was obtained on 1/4 MS (Murashige and Skoog,
1962) medium with 3% sucrose. Total alkaloid (aconites) content of transformed roots was 2.96%, which was 3.75 times higher
compared to 0.79% in the nontransformed (control) roots. Thin layer chromatography (TLC) analysis of the components of aconites
in the transformed roots revealed the presence of heteratisine, atisine, and hetidine. 相似文献
75.
A new alkaloid, scholaricine, has been isolated to which structure 2 (demethylscholarine) has been assigned. 相似文献
76.
Ammodendrine, together with seven other known lupin alkaloids, was isolated from Thermopsis lupinoides. (+)-Lupanine (+)-17-oxolupanine occurred together with (?)anagyrine, (?)-baptifoline, (?)-cytisine, (?)-N-methylcytisine (?)N-formylcytisine. These alkaloids have the opposite stereochemistry to that of (+)-lupanine and (+)-17-oxolupanine. The distribution of alkaloids in fresh flowers, leaves, stems roots of this plant was also examined. 相似文献
77.
78.
伊贝母组织培养中次生代谢产物的研究 总被引:6,自引:0,他引:6
以组织培养和细胞液印迹直接荧光观察法相结合,建立了伊贝母组织培养生物合成高含量贝母碱的技术,并通过薄层层析和薄层扫描对贝母生物碱的组成进行了比较分析。结果表明,不论是组织培养物还是栽培贝母中都含有母碱的主要成分-西贝素。但根中贝母碱的成分要比其它组织或器官中更为复杂,含量和活性也较高。继代培养8代的不定芽和不定根中贝母碱的含量分别高于栽培5年贝母根的0.01%和0.02%。 相似文献
79.
Five compounds were isolated from Buxus microphylla Sieb. et Zucc. Based on the physico-chemical constants and spectral analysis (IR, MS, 1H-NMR and 13C-NMR), they were identified as cycloprotobuxinamine ( Ⅰ ), buxmicrophylline A ( Ⅱ ), buxtauine M ( Ⅲ ), isoscopoletin (Ⅳ) and epi-lupeol ( Ⅴ ). ( Ⅰ ) and ( Ⅱ ) were new compounds. The structure of buxmicrophylline ( Ⅱ ) was confirmed by X-ray crystallographic analysis. 相似文献
80.
Ryo Nakabayashi Noriko Takeda-Kamiya Yutaka Yamada Tetsuya Mori Mai Uzaki Takashi Nirasawa Kiminori Toyooka Kazuki Saito 《Plant Biotechnology》2021,38(3):305
Plants release specialized (secondary) metabolites from their roots to communicate with other organisms, including soil microorganisms. The spatial behavior of such metabolites around these roots can help us understand roles for the communication; however, currently, they are unclear because soil-based studies are complex. Here, we established a multimodal metabolomics approach using imaging mass spectrometry (IMS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to spatially assign metabolites under laboratory conditions using agar. In a case study using Catharanthus roseus, we showed that 58 nitrogen (N)-containing metabolites are released from the roots into the agar. For the metabolite assignment, we used 15N-labeled and non-labeled LC-MS/MS data, previously reported. Four metabolite ions were identified using authentic standard compounds as derived from monoterpene indole alkaloids (MIAs) such as ajmalicine, catharanthine, serpentine, and yohimbine. An alkaloid network analysis using dot products and spinglass methods characterized five clusters to which the 58 ions belong. The analysis clustered ions from the indolic skeleton-type MIAs to a cluster, suggesting that other communities may represent distinct metabolite groups. For future chemical assignments of the serpentine community, key fragmentation patterns were characterized using the 15N-labeled and non-labeled MS/MS spectra. 相似文献