The use of the concept of privileged structures significantly accelerates the search for new leads and their optimization. 6-(methylsulfonyl)-8-(4-methyl-4-1,2,4-triazol-3-yl)-2-(5-nitro-2-furoyl)-2,6-diazaspiro[3.4]octane has been identified as a lead, with MICs of 0.
View Article and Find Full Text PDFA series of 13 new 3-substituted 5-(5-nitro-2-furyl)-1,2,4-oxadiazoles was synthesized from different aminonitriles. All compounds were screened in the disc diffusion test at a 100 μg/mL concentration to determine the bacterial growth inhibition zone presence and diameter, and then the minimum inhibitory concentrations (MICs) were determined for the most active compounds by serial dilution. The compounds showed antibacterial activity against ESKAPE bacteria, predominantly suppressing the growth of 5 species out of the panel.
View Article and Find Full Text PDFA series of 21 new 7'H-spiro[azetidine-3,5'-furo [3,4-d]pyrimidine]s substituted at the pyrimidine ring second position were synthesized. The compounds showed high antibacterial in vitro activity against . Two compounds had lower minimum inhibitory concentrations against (H37Rv strain) compared with isoniazid.
View Article and Find Full Text PDFVacuum ultraviolet (VUV) photodissociation of N molecules is a source of reactive N atoms in the interstellar medium. In the energy range of VUV optical excitation of N, the N-N triple bond cleavage leads to three types of atoms: ground-state N(S) and excited-state N(P) and N(D). The latter is the highest reactive and it is believed to be the primary participant in reactions with hydrocarbons in Titan's atmosphere.
View Article and Find Full Text PDFA series of eight 5-nitrofuran-tagged oxazolyl tetrahydropyrazolopyridines (THPPs) has been prepared in six stages with excellent regioselectivity. The testing of these compounds against pathogens of the ESKAPE panel showed a good activity of lead compound 1-(2-methoxyethyl)-5-(5-nitro-2-furoyl)-3-(1,3-oxazol-5-yl)-4,5,6,7-tetrahydro-1-pyrazolo[4,3-c] pyridine (), which is superior to nitrofurantoin. These results confirmed the benefit of combining a THPP scaffold with a nitrofuran warhead.
View Article and Find Full Text PDFRecent developments in the field of nanomedicine have introduced a wide variety of nanomaterials that are capable of recognizing and killing tumor cells with increased specificity. A major limitation preventing the widespread introduction of nanomaterials into the clinical setting is their fast clearance from the bloodstream via the mononuclear phagocyte system (MPS). One of the most promising methods used to overcome this limitation is the MPS-cytoblockade, which forces the MPS to intensify the clearance of erythrocytes by injecting allogeneic anti-erythrocyte antibodies and, thus, significantly prolongs the circulation of nanoagents in the blood.
View Article and Find Full Text PDFMulti-state electronic dynamics at higher excitation energies is needed for the understanding of a variety of energy rich situations, including chemistry under extreme conditions, vacuum ultraviolet (VUV) induced astrochemistry, and attochemistry. It calls for an understanding of three stages, energy acquisition, dynamical propagation, and disposal. It is typically not possible to identify a basis of uncoupled quantum states that is sufficient for the three stages.
View Article and Find Full Text PDFA small set of twelve compounds of a nitrofuran carboxamide chemotype was elaborated from a readily available 2,6-diazaspiro[3.4]octane building block, exploring diverse variants of the molecular periphery, including various azole substituents. The in vitro inhibitory activities of the synthesized compounds were assessed against H37Rv.
View Article and Find Full Text PDFThe synthesis of novel fluoroquinolones, congeners of ciprofloxacin, which was inspired by earlier work on spirocyclic ciprofloxacin, is described. An antibacterial evaluation of the 11 fluoroquinolone compounds synthesized against the ESKAPE panel of pathogens in comparison with ciprofloxacin revealed that the more compact spirocycles in the fluoroquinolone periphery resulted in active compounds, while larger congeners gave compounds that displayed no activity at all. In the active cohort, the level of potency was comparable to that of ciprofloxacin.
View Article and Find Full Text PDFJ Chem Theory Comput
February 2023
Unraveling the density matrix of a non-stationary quantum state as an explicit function of a few observables provides a complementary view of quantum dynamics. We have recently developed a practical way to identify the minimal set of the dominant observables that govern the quantal dynamics even in the case of strong non-adiabatic effects and large anharmonicity [Komarova et al., 204110 ()].
View Article and Find Full Text PDFStarting from a screening hit, a set of analogs was synthesized based on a 4-(2-aminoethyl)piperidine core not associated previously with trace amine-associated receptor 1 (TAAR1) modulation in the literature. Several structure-activity relationship generalizations have been drawn from the observed data, some of which were corroborated by molecular modeling against the crystal structure of TAAR1. The four most active compounds (EC for TAAR1 agonistic activity ranging from 0.
View Article and Find Full Text PDFWe introduce a practical method for compacting the time evolution of the quantum state of a closed physical system. The density matrix is specified as a function of a few time-independent observables where their coefficients are time-dependent. The key mathematical step is the vectorization of the surprisal, the logarithm of the density matrix, at each time point of interest.
View Article and Find Full Text PDFWe report on fully quantum electronic-nuclear dynamics following sudden ionization from the neutral in the three lowest electronic states of the CH and CD cations. There is a strong Jahn-Teller effect in the Franck-Condon region, and we employ two nuclear degrees of freedom that span the internal coordinates involved in the Jahn-Teller coupling. The initial state results from tunneling ionization by a strong IR field which coherently pumps the three lowest states of the cation, D, D, and D.
View Article and Find Full Text PDFAtto- and sub-femto-photochemistry enables preparation of molecules in a coherent superposition of several electronic states. Recently [Ajay et al., Proc.
View Article and Find Full Text PDFProgress toward quantum technologies continues to provide essential new insights into the microscopic dynamics of systems in phase space. This highlights coherence effects whether these are due to ultrafast lasers whose energy width spans several states all the way to the output of quantum computing. Surprisal analysis has provided seminal insights into the probability distributions of quantum systems from elementary particle and also nuclear physics through molecular reaction dynamics to system biology.
View Article and Find Full Text PDFOur quantum device is a solid-state array of semiconducting quantum dots that is addressed and read by 2D electronic spectroscopy. The experimental ultrafast dynamics of the device is well simulated by solving the time-dependent Schrödinger equation for a Hamiltonian that describes the lower electronically excited states of the dots and three laser pulses. The time evolution induced in the electronic states of the quantum device is used to emulate the quite different nonequilibrium vibrational dynamics of a linear triatomic molecule.
View Article and Find Full Text PDFThe chiroptical properties of multi-chromophoric systems are governed by the intermolecular arrangement of the monomeric units. We report on a computational and experimental study of the linear optical properties and supramolecular structure of a rhodamine heterodimer assembled on a DNA scaffold. The experimental absorption and circular dichroism (CD) profiles confirm the dimer formation.
View Article and Find Full Text PDFComb Chem High Throughput Screen
August 2020
Introduction: A variety of organic compounds has been reported to have antibacterial activity. However, antimicrobial resistance is one of the main problems of current anti-infective therapy, and the development of novel antibacterials is one of the main challenges of current drug discovery.
Methods: Using our previously developed dual-reporter High-Throughput Screening (HTS) platform, we identified a series of furanocoumarins as having high antibacterial activity.
The time evolution of a vacuum ultraviolet excited N molecule is followed all the way from an ultrafast excitation to dissociation by a quantum mechanical simulation. The primary aim is to discern the role of the excitation by a pulse short compared to the vibrational period, to discern the different coupling mechanisms between different electronic states, nonadiabatic, spin orbit, and to analyze the origin of any isotopic effect. We compare the picture in the time and energy domains.
View Article and Find Full Text PDFThe present report describes our efforts to identify new structural classes of compounds having promising antibacterial activity using previously published double-reporter system pDualrep2. This semi-automated high-throughput screening (HTS) platform has been applied to perform a large-scale screen of a diverse small-molecule compound library. We have selected a set of more than 125,000 molecules and evaluated them for their antibacterial activity.
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