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21.
Zdravko Džambaski Đorđe Toljić Bojan Bondžić Rade Marković Marija Baranac-Stojanović 《Tetrahedron》2013
The reactivity of 2-alkylidene-4-oxothiazolidine S-oxides under the Pummerer reaction conditions, using Ac2O, TFAA, SOCl2 and SOBr2 as initiators, has been examined. Almost all reactions proceeded with absolute regioselectivity yielding α-substituted sulfides or vinyl-chloro derivatives. The mechanism for the formation of the latter products was postulated and proved experimentally. 相似文献
22.
Slobodanka Stankovi Duan Lazar Ljubica Medi‐Mija
evi Katarina Penov‐Gai Marija Saka
Silvana Andri Bruvo Milenko 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o172-o173
The title molecule, C26H30O3, shows a novel chemical rearrangement of the substituents at position 17, i.e. an α‐orientation of the hydroxy group and a β‐orientation of the bulky benzyl moiety. The packing arrangement consists of coils formed by O2?O3 hydrogen bonds along the c axis. The compound shows complete loss of oestrogenic activity, and neither does it exhibit an antagonistic effect. 相似文献
23.
Senka Djakovi Ljubica Glava‐Obrovac Jasmina Lapi Silvija Mara
i Juraj Kirchofer Marija Kneevi Marijana Juki Silvana Rai‐Mali 《应用有机金属化学》2021,35(1)
Mono‐ ( 3a – 3e and 4a – 4e ) and bis‐ferrocene ( 5a – 5e and 6a – 6e ) conjugated 5‐substituted uracil derivatives that are bridged by 1,2,3‐triazole linker were synthesized. The impact of ferrocene unit and spacer between ferrocene and triazole on radical scavenging potency was observed. Bis‐ferrocenyl uracil derivatives exhibited better antiproliferative activities than their mono‐ferrocenyl analogs. Bis‐ferrocenyl methyl‐ ( 5b ) and halogen‐substituted ( 5e , 6c , and 6d ) uracil derivatives showed pronounced and selective cytostatic activities on colon adenocarcinoma (CaCo‐2) and Burkitt lymphoma (Raji) cells, with higher potency and selectivity than the reference drug 5‐fluorouracil. Generation of reactive oxygen species (ROS) in CaCo‐2 and Raji cells when treated with compounds 5b , 5e , and 6d was observed. Bis‐ferrocenyl 5‐chlorouracil 6c induced significant disruption in mitochondrial membrane potential that is accompanied by activation of apoptosis in CaCo‐2, Raji, and acute lymphoblastic leukemia (CCRF‐CEM) cells, while 6d caused mitochondrial dysfunction and apoptosis induction in CaCo‐2 and Raji cells. Potent antiproliferative activity of 6c and 6d could be associated with mitochondrial membrane potential disruption accompanied by apoptosis induction. Our findings highlighted 6c and 6d with potent and selective antiproliferative activity on CaCo‐2, Raji, and CCRF‐CEM cells that may be associated with targeting cancer cell mitochondria, as a molecular target. 相似文献
24.
Ribić Rosana Kodrin Ivan Biljan Ivana Paurević Marija Tomić Srđanka 《Structural chemistry》2019,30(3):743-754
Structural Chemistry - Muropeptides are fragments of polymeric peptidoglycan, unique constituent of bacterial cell walls, acting as immunostimulators (adjuvants). The smallest biologically active... 相似文献
25.
Goran M. Petrović Marija D. Ilić Vesna P. Stankov-Jovanović Gordana S. Stojanović Snežana Č. Jovanović 《Natural product research》2018,32(3):331-334
Phytochemical analysis by GC and GC/MS of the essential oil samples obtained from fresh shoots and flowers of Saponaria officinalis L. allowed the identification of 96 components in total, comprising 94.7% and 86.0% of the total oils compositions, respectively. Regarding the shoots essential oil, the major of 87 identified volatile compounds were phytol (14.1%), tricosane-6,8-dione (13.4%), patchouli alcohol (7.9%) and tricosane (7.2%), whereas patchouli alcohol (20.0%), heneicosane (11.5%) and tricosane (8.4%) were dominant among the 66 volatiles in the flower oil. Nonterpenoid compounds had the highest contribution in S. officinalis shoots essential oil (53.7%), while in the flower oil, constituents were almost evenly distributed between the oxygenated sesquiterpenoid (41.2%) and nonterpenoid compounds (39.5%). 相似文献
26.
Janković Bojan Dodevski Vladimir Stojmenović Marija Krstić Sanja Popović Jasmina 《Journal of Thermal Analysis and Calorimetry》2018,133(1):465-480
Journal of Thermal Analysis and Calorimetry - Raw and pyrolyzed samples of the plane tree seeds (PTS) were tested by various advanced analytical techniques including simultaneous TG-DSC technique,... 相似文献
27.
Adela Štimac Jasmina Lapić Valentino Blasina Marija Lukinac Senka Djaković Ivo Crnolatac Leo Frkanec Ruža Frkanec 《应用有机金属化学》2018,32(2)
A series of homoannularly and heteroannularly substituted adamantyl ferrocene derivatives has been synthesized and their effects on membrane fluidity were investigated using liposomes as the membrane models. The liposome formulations of adamantyl ferrocene derivatives were characterized by using dynamic light scattering, differential scanning calorimetry and fluorescence anisotropy measurements. It was demonstrated that adamantyl ferrocene derivatives incorporated into the liposome significantly affect the structure of the lipid bilayer. The results of the study have revealed that adamantyl ferrocene derivatives, compounds 9 – 12, partition into the hydrophobic/hydrophilic interface of the membrane, causing a significant decrease in membrane fluidity. The antioxidant potential of synthesized compounds was assessed with DPPH method and it was shown that the examined compounds possess certain antioxidant activity. 相似文献
28.
Slobodan??iri?Email authorView authors OrcID profile Violeta?Miti? Sne?ana?Jovanovi? Marija?Ili? Jelena?Nikoli? Gordana?Stojanovi? Vesna?Stankov Jovanovi? 《Mikrochimica acta》2018,185(12):556
The authors report on a novel sorbent (thermally treated natural zeolite; clinoptilolite) for use in dispersive micro-solid phase extraction (D-μ-SPE) of polycyclic aromatic hydrocarbons (PAHs) from water samples. The method was applied to the D-μ-SPE of 16 priority PAHs which then were quantified by gas chromatography with mass spectrometric detection (GC-MS). The method was validated in terms of specificity and selectivity, linearity and linear range, accuracy, precision, uncertainty, limits of detection and quantification. Figures of merit include (a) linear analytical ranges between 2.08 and 208 ppb, and (b) detection limits in the range from 0.01 to 0.92 ppb. The method was successfully applied to the determination of PAHs in river waters. 相似文献
29.
30.
M. Vuković 《Journal of Electroanalytical Chemistry》1982,133(1):25-32
An extension of double-potential-step chronocoulemetry to multiple or cyclic techniques has been developed, and its potential applications in the study of coupled chemical reactions in electrochemistry are discussed. Disproportionation and dimerization mechnisms are considered. Wroking curves have been calculated with the use of the finite difference digital simulation method. It is shown that better resolution for disproportionation and dimerization reactions can be obtained with cyclic chronocoulometry than with double-potential-step chronocoulemetry. The method has been experimentally verified measuring the disproportionation reaction U(V) in 1 mol dm?3 sodium hydrogen carbonate solutions. A rate coefficient of 15.6 dm3 mol?1 was calculated for this reaction. 相似文献