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91.
Enantiopurity analysis of new types of acyclic nucleoside phosphonates by capillary electrophoresis with cyclodextrins as chiral selectors
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Veronika Šolínová Martin Maxmilián Kaiser Miloš Lukáč Zlatko Janeba Václav Kašička 《Journal of separation science》2014,37(3):295-303
CE methods have been developed for the chiral analysis of new types of six acyclic nucleoside phosphonates, nucleotide analogs bearing [(3‐hydroxypropan‐2‐yl)‐1H‐1,2,3‐triazol‐4‐yl]phosphonic acid, 2‐[(diisopropoxyphosphonyl)methoxy]propanoic acid, or 2?(phosphonomethoxy)propanoic acid moieties attached to adenine, guanine, 2,6‐diaminopurine, uracil, and 5‐bromouracil nucleobases, using neutral and cationic cyclodextrins as chiral selectors. With the exception of the 5‐bromouracil‐derived acyclic nucleoside phosphonate with a 2‐(phosphonomethoxy)propanoic acid side chain, the R and S enantiomers of the other five acyclic nucleoside phosphonates were successfully separated with sufficient resolutions, 1.51–2.94, within a reasonable time, 13–28 min, by CE in alkaline BGEs (50 mM sodium tetraborate adjusted with NaOH to pH 9.60, 9.85, and 10.30, respectively) containing 20 mg/mL β‐cyclodextrin as the chiral selector. A baseline separation of the R and S enantiomers of the 5‐bromouracil‐derived acyclic nucleoside phosphonate with 2‐(phosphonomethoxy)propanoic acid side chain was achieved within a short time of 7 min by CE in an acidic BGE (20:40 mM Tris/phosphate, pH 2.20) using 60 mg/mL quaternary ammonium β‐cyclodextrin chiral selector. The developed methods were applied for the assessment of the enantiomeric purity of the above acyclic nucleoside phosphonates. The preparations of all these compounds were found to be synthesized in pure enantiomeric forms. Using UV absorption detection at 206 nm, their concentration detection limits were in the low micromolar range. 相似文献
92.
A. V. Belyankin A. R. Khomutov Yu. N. Zhukov O. N. Kartasheva R. M. Khomutov 《Russian Chemical Bulletin》1997,46(1):133-136
The reaction of aryl and aralkyl aldoximes with hypophosphorous acid resulted in aminophosphinic acids, which were oxidized
into the corresponding aminophosphonic acids.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 137–140, January, 1997. 相似文献
93.
R. M. Zolotar' A. I. Bykhovets V. L. Survilo N. V. Kovganko 《Chemistry of Natural Compounds》2002,38(5):439-442
Structural analogs of ecdysteroids were screened for insecticidal activity for larvae of the Colorado beetle Leptinotarsa decemlineata using a contact-feed method. High activity was found for compounds 3, 6b, 7a, and 9a. 相似文献
94.
The reaction of lanthanide shift reagents with the heterocyclic analogs of substituted 2'-alkoxychalcones was studied. It was shown that the coordination of Eu(fod)3 and Yb(fod)3 with them takes place in different ways. The former forms mainly adducts of the chelate type with participation of the oxygen atoms of the carbonyl and alkoxyl groups in coordination, while from the latter only the adduct at the carbonyl group is obtained. For this reason it was concluded that there are some limitations to the use of the reagents for conformational analysis of organic compounds. It was shown that they can only be used to study the conformational movements of the molecules not affecting the complexation process. 相似文献
95.
A series of novel daphneolone analogs was designed and synthesized on the basis of natural product 1,5-diphenyl-2-penten-1-one(I) from Stellera chamaejasme L. as lead compound, whereby 2,6-dimethylmorpholine moiety was introduced to replace 1-phenyl group. Their structures were confirmed by IR,1H NMR, and HRMS(ESI) or elemental analysis,13 C NMR for some representative compounds. The two isomers of target compounds were separated and identified by NOESY technique and chemical method.All of the synthesized compounds have been evaluated for anti-plant pathogenic fungi activities. The results showed that some compounds exhibited moderate to good antifungal activities against tested fungi at the concentration of 50 mg/L. Among them, compound 7d, with a 4-bromine-substituted phenyl group and cis-2,6-dimethylmorpholine moiety, displayed best activity with an EC50 of 23.87 mmol/L against Valsa mali, superior to lead compound I. In addition, preliminary structure–activity relationship analysis indicated that, between two isomers of target compounds, the antifungal activities of the isomer with cis-2,6-dimethylmorpholine were better than the trans-isomer. 相似文献
96.
The pseudopterosins are marine natural products that display significant anti-inflammatory and wound healing properties. We describe the synthesis of six structural analogs of the seco-pseudopterosin-like core that are devoid of all but one of the stereocenters found in the carbocyclic core of the natural products. Our targets were selected in an attempt to identify the minimal pharmacophore for the pseudopterosins and their seco analogs. A deliberate effort was made to utilize a conservative synthetic approach based upon the use of well-established reactions, which enabled us to develop routes that proved to be efficient, practical, and easy to implement. The results of several bioassays, including an assessment of the ability to inhibit phagocytosis and to competitively bind to the adenosine receptor A2A, demonstrate that greatly simplified structural analogs of the pseudopterosins and their seco forms are capable of maintaining several of the important bioactivities that characterize the natural products, and do so with comparable efficacy. Those systems bearing two rather than one oxygen atom appended directly to the aromatic ring are the more effective binding agents. This observation may provide a significant clue regarding the key structural features of the minimal pharmacophore. 相似文献
97.
Jia Rong Li Li Jun Zhang Xi Quan Yang Qing Li Dong Wang Chun Xia Wang Da Xin Shi Qi Zhang 《中国化学快报》2008,19(1):15-18
Two different skeletons of heterocyclic compounds, quinoline and quinazolinone analogs could be obtained by a novel one-pot synthesis from substituted 3-amino- 1H-benzo[f]chromene-2-carbonitrile derivatives and cyclohexanone in DMF in the catalyst of anhydrous Zinc chloride under reflux. A plausible mechanism was proposed. 2007 Jia Rong Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 相似文献
98.
S. P. Gromov A. I. Vedernikov E. N. Ushakov M. V. Alfimov 《Russian Chemical Bulletin》2008,57(4):793-801
The results of the comprehensive study of novel supramolecular donor-acceptor complexes of bis(crown)stilbenes and bis(crown)azobenzene
with viologen analogs are generalized. The original methodology for self-assembling of the organic donor-acceptor complexes
possessing a very high thermodynamic stability is described. The hydrogen bonds between the peripheral fragments of the donor
and acceptor play the key role in the self-assembling. The influence of different structural factors on the thermodynamic
stability of the supramolecular donor-acceptor complexes and the efficiency of charge-transfer interactions between the donor
and acceptor are discussed. The driving forces of the reaction leading to exotic trimolecular charge-transfer complexes are
considered.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 779–787, April, 2008. 相似文献
99.
《Mendeleev Communications》2023,33(4):469-471
Thz-Phe-D-Trp-Lys-Thr-DOTA, a conjugate of the DOTA chelator and the Thz-Phe-D-Trp-Lys-Thr pentapeptide, was labeled with 152Eu and 161Tb radionuclides, where 161Tb has decay characteristics suitable for its use in cancer therapy. For the [152Eu]Eu-Thz-Phe-D-Trp-Lys-Thr-DOTA complex, the biodistribution in nude mice bearing IMR-32 tumors was evaluated for the first time. It was shown that the complexes of the conjugate demonstrate accumulation in the tumor at the level of DOTA-TATE, another peptide conjugate widely used in nuclear medicine for the diagnosis and therapy of neuroendocrine tumors, which allows Thz-Phe-D-Trp-Lys-Thr-DOTA to be considered as a potential biological vector for radiopharmaceuticals. 相似文献
100.
Si Yan Liao Li Qian Jin Can Chen Hai Liang Lu Kang Cheng Zheng 《International journal of quantum chemistry》2008,108(8):1380-1390
Two‐dimensional (2D) and three‐dimensional (3D) quantitative structure–activity relationships (QSARs) of 22 thiazolidine analogs with antiproliferative activity expressed as pIC50, which is defined as the negative value of the logarithm of necessary molar concentration of these compounds to cause 50% growth inhibition against melanoma cell lines WM‐164, have been studied by using a combined method of the DFT, MM2 and statistics for 2D, as well as the comparative molecular field analysis (CoMFA) method for 3D. The established 2D‐QSAR model in training set comprised of random 18 compounds shows not only significant statistical quality, but also predictive ability, with the square of adjusted correlation coefficient (R = 0.832) and the square of the cross‐validation coefficient (q2 = 0.803). The same model was further applied to predict pIC50 values of the four compounds in the test set, and the resulting R reaching 0.784, further confirms that this 2D‐QSAR model has high predictive ability. The 3D‐QSAR model also shows good correlative and predictive capabilities in terms of R2 (0.956) and q2 (0.615) obtained from CoMFA model. Further, the robustness of the CoMFA model was verified by bootstrapping analysis (100 runs) with R (0.979) and SDbs (0.056). It is very interesting to find that the results from 2D‐ and 3D‐QSAR analyses accord with each other, and they all show that the steric interaction plays a crucial role in determining the cytotoxicities of the compounds, and that selecting a moderate‐size or appropriate‐hydrophobicity substituent R as well as increasing the negative charges of C4 on phenyl ring at the same time are advantageous to improving the cytotoxicity. Such results can offer some useful theoretical references for directing the molecular design and understanding the action mechanism of this kind of compound with antiproliferative activity. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 相似文献