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91.
Noor Shahina Begum D. E. Vasundhara C. R. Girija M. Narendra Mallya Gopalpur Nagendrappa 《Journal of chemical crystallography》2008,38(7):547-551
Abstract The crystal and molecular structure of cis-1-chloro-2-amino-1-trimethylsilylcycloheptane picrate (cis-CATP) is determined and discussed along with its spectroscopy. The crystal structure of this compound (C10H23SiClN+ C6H2N3O7−) consists of ammonium cycloheptane cation and picrate anion stabilized by interionic N–H···O and C–H···O interactions leading
to extended hydrogen bonded network structure. Apart from the less common syn addition of nitrosylchloride to 1-trimethylsilylcycloheptene ring, an interesting and unexpected reversal of regiochemistry
of addition is revealed.
Index Abstract The preparation of cis-1-chloro-2-ammonium-1-trimethylsilylcycloheptane picrate is described and its crystal structure is determined and discussed.
相似文献
92.
Farrah Syazana Khattulanuar Mahendran Sekar Shivkanya Fuloria Siew Hua Gan Nur Najihah Izzati Mat Rani Subban Ravi Kumarappan Chidambaram M. Yasmin Begum Abul Kalam Azad Srikanth Jeyabalan Arulmozhi Dhiravidamani Lakshmi Thangavelu Pei Teng Lum Vetriselvan Subramaniyan Yuan Seng Wu Kathiresan V. Sathasivam Neeraj Kumar Fuloria 《Molecules (Basel, Switzerland)》2022,27(3)
Cardiovascular disorders (CVDs) are the leading risk factor for death worldwide, and research into the processes and treatment regimens has received a lot of attention. Tilianin is a flavonoid glycoside that can be found in a wide range of medicinal plants and is most commonly obtained from Dracocephalum moldavica. Due to its extensive range of biological actions, it has become a well-known molecule in recent years. In particular, numerous studies have shown that tilianin has cardioprotective properties against CVDs. Hence, this review summarises tilianin’s preclinical research in CVDs, as well as its mechanism of action and opportunities in future drug development. The physicochemical and drug-likeness properties, as well as the toxicity profile, were also highlighted. Tilianin can be a natural lead molecule in the therapy of CVDs such as coronary heart disease, angina pectoris, hypertension, and myocardial ischemia, according to scientific evidence. Free radical scavenging, inflammation control, mitochondrial function regulation, and related signalling pathways are all thought to play a role in tilianin’s cardioprotective actions. Finally, we discuss tilianin-derived compounds, as well as the limitations and opportunities of using tilianin as a lead molecule in drug development for CVDs. Overall, the scientific evidence presented in this review supports that tilianin and its derivatives could be used as a lead molecule in CVD drug development initiatives. 相似文献
93.
94.
Numerical calculations have been done of the viscosity of the soft-sphere liquid, using a new molecular dynamics technique. It is based on a formulation of hydrodynamics which is discrete in space and time, and exactly renormalizable. The present data turn out to be sufficient to estimate the viscosity, but determination of the full equations of motion (and therefore renormalization) requires further calculations using a smaller discrete time interval; these are presently under way. The present results indicate that this method is more than 100 times more efficient than previous (Green-Kubo or nonequilibrium molecular dynamics) methods. This suggests that the discrete formulation is the most natural way to approach hydrodynamics. 相似文献
95.
Ohne Zusammenfassung 相似文献
96.
Etmina Ahmed Sultanuddin Ahmed Afroza Begum Abul Khair Ashim K. Roy 《Transition Metal Chemistry》1986,11(7):271-273
Summary Oxygenation of [Co(pd)2(H2O)2] (Hpd = 2,4-pentanedione) in the presence of triphenylphosphine forms [Co(pd)3] and a peroxo-complex that shows strong v(O-O) at 865 cm–1. The mechanism of Co-pd cleavage and the concomitant formation of [Co(pd)3] are discussed. With guanidine carbonate the title compound forms a carbonato-complex, (CH5N3H)2-[Co(CH5N3)(CO3)2] · H2O, which is the violet component of the so-called blue-violet pair of the complexes of the general formula [CoA2(CO3)2]2– (A2 = ethylenediamine or 2NH3). The carbonato-complex is assigned either a square-pyramidal geometry with monodentate CH5N3 or a polymeric octahedral structure with a bridging CH5N3 group. 相似文献
97.
Khan KM Saify ZS Begum S Noor F Khan MZ Hayat S Choudhary MI Perveen S Atta-Ur-Rahman Zia-Ullah 《Natural product research》2003,17(2):115-125
7-Hydroxy-4-methyl-2H-chromen-2-one (2), 7-hydroxy-4,5-dimethyl-2H-chromen-2-one (15) and their some derivatives were synthesized for exploring selected biological screening. The compounds 9 and 13 had shown high degree of cytotoxic activity. Three compound 9, 10 and 13 showed high degree of bactericidal activity amongst the present series. 相似文献
98.
The rearrangement of the actin cytoskeleton has been shown to play a critical role in the development of transformation and malignant phenotype of cancer cells. Rho family GTPases regulate the arrangement of the actin cytoskeleton. By wound-healing assay, we have found that NIH 3T3 fibroblast cells move towards the wound- gaps by extending filopodial and lamellipdial structures at the leading edge of the moving cells. We have inactivated the function of Rho GTPases of v-Ras transformed NIH 3T3 cells by overexpressing Rho GTPase-activating (RhoGAP) domain of RhoGAP of p190. We have observed that inactivation of Rho, Rac and Cdc42 GTPases by overexpressing RHG causes inhibition of: (i) polymerization of actin to form filaments, (ii) formation of lamellipodia, filopodia and stress fibres, (iii) cell motility, (iv) cell spreading and (v) cell-to-cell adhesions. These results further strengthen the current knowledge on the role of Rho, Rac and Cdc42 GTPases in the regulation of the rearrangement of actin cytoskeleton. Our results, for the first time, demonstrate that RhoGAP domain of RhoGAP could be used to study the molecular mechanism of Ras-mediated signalling in growth, differentiation and carcinogenesis. 相似文献
99.
Three pentacyclic triterpenoids including one new guajavanoic acid (2) and two known obtusinin (1) and goreishic acid I (3) have been isolated from the leaves of Psidium guajava. The new constituent 2 has been characterized as 2alpha-hydroxy-3beta-p-E-coumaroyloxyurs-12, 18-dien-28-oic acid through 1H-NMR and 13C-NMR (broad band and DEPT). This is the first report of isolation of compound 1 and 3 from the genus Psidium. 相似文献
100.
Noorjahan Begum Mohammad Islam Dalia Rokhsana 《Journal of organometallic chemistry》2004,689(16):2633-2640
The valence saturated benzothiazolide triosmium cluster [Os3(CO)10(μ-η2-C7H4NS)(μ-H)] (1) reacts with tetramethylthiourea in refluxing toluene to give [Os3(CO)8(μ-η2-C7H4NS)(η2-SCNMe2NMeCH2)(μ-H)2] (5), which exists as a mixture of two isomers in solution, whereas the electron-deficient cluster [Os3(CO)9(μ3-η2-C7H4NS)(μ-H)] (2) reacts with tetramethylthiourea in refluxing cyclohexane to give two new compounds [Os3(CO)8(μ-η2-C7H4NS)(η2-SCNMe2NMeCH2)(μ-H)2] (6) and [Os3(CO)9(μ-η2-C7H4NS)(η1-SC(NMe2)2)(μ-H)] (7). In contrast, the reaction of [Os3(CO)9(μ3-η2-C7H3(2-CH3)NS)(μ-H)](3) with tetramethylthiourea in refluxing cyclohexane at 81 °C, gives only [Os3(CO)9(μ-η2-C7H3(2-CH3)NS)(η1-SC(NMe2)2)(μ-H)] (8) in 15% yield. Compound 7 converts into 6 in refluxing toluene whereas a similar thermolysis of 8 results non-specific decomposition. All the compounds have been characterized by elemental analysis, IR, 1H NMR and mass spectroscopic data together with single crystal X-ray diffraction analysis for 5 and 7. Both compounds 5 and 6 contain a cyclometallated tetramethylthiourea ligand which is chelating at the rear osmium atom and are structurally very similar. In 5, the benzothiazolide ligand is coordinated to Os3 triangle via the nitrogen lone pair and C(2) carbon atom of the heterocyclic ring whereas in 6 the ligand is coordinated to the Os3 triangle via the nitrogen lone pair and the C(7) carbon atom of carbocyclic ring. In 7 and 8, the tetramethylthiourea ligand is coordinated at an equatorial site of the osmium atom which is also bound to the nitrogen atom of the benzothiazolide ligand. 相似文献