27 research outputs found
Role of Metal Ions and Hydrogen Bond Acceptors in the Tautomeric Equilibrium of Nitro-9[(Alkylamino)Amino]-Acridine Drugs
3-nitro-9-[2-(dialkylamino)ethyl)]aminoacridines (alkyl = methyl or ethyl) have been used as ligands
towards platinum(If). The end product is a complex in which the acridine acts as a tridentate ligand
contributing the two exocyclic nitrogen atoms and one of the two peri carbons. The metallation takes place
predominantly at the peri position of the unsubstituted ring. The coordinated acridine is in the imino
tautomeric form although, in the free state, it occurs exclusively in the amino form (both in the solid state and
in solution). The imino tautomer is considered to be the biologically active form. In the platinated species the
N(10)H of the acridine can be involved in strong hydrogen bonding with a chloride ion leading to formation
of an association complex, the formation constant has been found to be 1.4±103 M−1. The N(10)H┄CI
interaction can influence the tautomeric equilibrium of the acridine dye also in the uncoordinated species,
however, the shift in favor of the imino tautomer is not complete
Inhibition pattern of sulfamide-related compounds in binding to carbonic anhydrase isoforms I, II, VII, XII and XIV
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Seismic noise cross-correlation in the urban area of Benevento city (Southern Italy)
This article has been accepted for publication in Geophysical Journal International ©: The Authors 2019. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. Uploaded in accordance with the publisher's self-archiving policy.In the last decade the use of passive methods has become appealing in reconstructing the properties of the propagation medium by seismic ambient noise data, without the use of localized natural or artificial sources. A temporary seismic network was installed in the urban area of Benevento (southern Italy) in order to characterize the shallow structure of the city using stable methods for the analysis of the seismic noise continuously acquired by stations. The city of Benevento is one of the italian areas with highest seismic hazard, and at present the region is affected by low energy swarms and sparse events (Ml ≤ 4.1). It has been struck by several destructive historical earthquakes, the strongest of which occurred in 1456, 1688, 1805 with associated MCS intensity up to X–XI. We used the sixteen seismic stations installed in Benevento to record ambient noise for about 1 month. The stations were equipped with different seismic instruments: (i) digitizers Quanterra Q330 connected to Le3d-5 s short-period sensors; (ii) Nanometrics Centaur digitizers coupled with Trillium Compact 120s broad-band velocimeters; (iii) one station with Episensor force balance accelerometer connected to a D6BB-DIN Staneo digitizer. Interstations Green's functions were reconstructed by the cross-correlation of continuous ambient noise data, and surface waves signals were extracted from Green's Functions (GFs) for investigating the elastic properties of the subsurface structure. In this regard, we performed the beamforming analysis to test the hypothesis of isotropy distribution of noise sources on which the cross-correlation method is based, and the particle motion analysis to confirm the presence of surface Rayleigh waves in the GFs. We analysed the temporal stability of the cross-correlated signals and the results show that 2 weeks of continuous measurements are sufficient to stabilize the surface waves signal extracted from the GFs. The phase velocity dispersion curves are computed for 115 station pairs through the use of a far-field representation of the surface-wave GFs and an image transformation technique. Our strategy based on cross-correlation analysis provides robust phase-velocity dispersion curves that vary approximately from 1.4 km s–1 at 0.7 Hz to 0.6 km s–1 at 5 Hz. Different pairs were selected for the inversion of phase-velocity dispersion curves aimed to derive 1-D shear-wave velocity (Vs) profiles (up to a maximum depth of about 500 m) representative of some areas of the city characterized by different soil deposits.Published1524–15425T. Sismologia, geofisica e geologia per l'ingegneria sismicaJCR Journa
Inhibition pattern of sulfamide-related compounds in binding to carbonic anhydrase isoforms I, II, VII, XII and XIV
A set of sulfamides and sulfamates were synthesized and tested against several isoforms of carbonic anhydrase: CA I, CA II, CA VII, CA XII and CA XIV. The biological assays showed a broad range of inhibitory activity, and interesting results were found for several compounds in terms of activity (Ki <1μm) and selectivity: some aromatic sulfamides are active against CA I, CA II and/or CA VII; while they are less active in CA XII and CA XIV. On the other hand, bulky sulfamides are selective to CA VII. To understand the origin of the different inhibitory activity against each isozyme we used molecular modeling techniques such as docking and molecular dynamic simulations.Facultad de Ciencias Exacta
Complexes of osazones with palladium(II) and platinum(II): Isomerization, oxidation, and ortho-metallation of the co-ordinated ligands
The preparation, properties, and reactions of a series of complexes of general formula [MCl2(L)] are described for the first time (M = Pt) or reinvestigated (M = Pd) [L = Ph(H)N·N:[graphic omitted]:N·N(H)Ph (L1), Ph(H)N·N:C(Me)·C(Me):N·N(H)Ph (L2), and Ph(Me)N·N:C(Me)·C(Me):N·N(Me)Ph (L3)]. On treatment with base, complexes of L1 and L2 readily undergo hydrogen-chloride elimination to give species of formula [{MCl(L - H)}x] which contain a covalent M-N bond. These complexes in solution undergo further transformation with loss of a hydrogen molecule and formation of ortho-metallated diazoalkene derivatives, [M(L - 3H)Cl]. The complex [PtCl2(L3)], on treatment with silica gel or refluxing in nitromethane, affords, as the palladium analogue, the cyclometallated species [PtCl(L3 - H)]. The reactivities of the ligands with palladium and platinum fire compared