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RSA is a well-known public key cryptosystem in modern-day cryptography. Common prime RSA (CP-RSA) is a variant of RSA which is introduced by Wiener to avoid the small secret exponent attack on RSA. Lattice-based reduction algorithms were successfully used for cryptanalysis for RSA and its variants. In this paper, we mount an attack on CP-RSA by following the Jochemsz and May approach. Jochemsz and May approach is the standard way to construct the lattices for the attacks on RSA and its variants. Our attack improves the bounds of attacks on standard RSA and CP-RSA.

We report a novel blue LED mediated intramolecular C–H functionalization of tryptamine derivatives to generate azepino[4, 5-b]indoles (4) in moderate to good yields. By altering the substitution at the tryptamine nitrogen, intramolecular cyclopropanation is achieved in high yields under the same reactions condition to provide natural product inspired polycyclic indoles (6), which are further transformed to spiropiperidino (5and 8) indoles in decent yields. The mechanism of formation of the compounds was investigated through DFT studies.

The investigation of proton localization at a hydrophobic–hydrophilic interface is an important problem in chemical and materials sciences. In this study, protonated benzene (i.e., benzenium ion) and water clusters [BZH+Wn(where n= 1–6)] are selected as prototype models to understand the interfacial interactions and proton transfer mechanism between a carbonaceous surface and water molecules. The excess protons can localize in the vicinity of the hydrophobic–hydrophilic interface, and these clusters are stabilized by various kinds of noncovalent interactions. Calculations are carried out using ab initio(MP2) and density functional theory B3LYP methods to shed more light on geometries, energetics, and spectral signatures of the protonated species [H+(H2O)n] at the interfaces. These calculations revealed few low-lying isomers, which have not been reported earlier. Scrutiny of the results reveals that proton localization in the hydrophilic environment is more stable than the hydrophobic benzene π-cloud. Furthermore, the occurrence of an O–H+···π hydrogen bond significantly influences the O–H+···O interactions in the water clusters and also intensively affects the vibrational modes of the Eigen cation. Thus, the aromatic π-clouds can stabilize the Eigen cation and at the same time, a twisted form of Eigen (one O–H+···π → two O–H+···π) can enhance the proton transfer through the water chain viaa Grotthuss-typemechanism. The vibrational spectra of these clusters reveal that there is a large red-shifted frequency for the O–H+···O, O–H+···π, and O–H···π modes of interaction. The energetic values and vibrational frequencies obtained from the B3LYP method are in close agreement with the MP2 level and experimental values, respectively.

Isobutyraldehyde underwent auto-oxidation in the presence of molecular oxygen to generate an acyloxy radical under a “metal-free” environment. They were subsequently exploited in situto afford hypervalent iodines with p-anisolyl iodide which generated substituted 1,3,4-oxadiazoles in moderate to excellent yields from N′-arylidene acetohydrazides. The reaction strategy tolerated diverse substitution on the hydrazide substrates. Control experiments and literature precedence supported the formation of an in situiodosylarene complex that facilitates the formation of products.

Blends of π-conjugated polymers and fullerene derivatives are ubiquitous as the active layers of organic solar cells. However, a detailed understanding of the weak noncovalent interactions at the molecular level between the polymer chains and fullerenes is still lacking and could help in the design of more efficient photoactive layers. Here, using a combination of long-range corrected density functional theory calculations and molecular dynamic simulations, we report a thorough characterization of the nature of binding between fullerenes (C60and PC61BM) and poly(benzo[1,2-b:4,5-b′]dithiophene–thieno[3,4-c]pyrrole-4,6-dione) (PBDTTPD) chains. We illustrate the variations in binding strength when the fullerenes dock on the electron-rich vs electron-poor units of the polymer as well as the importance of the role played by the polymer and fullerene side chains and the orientations of the PC61BM molecules with respect to the polymer backbones.

Highly efficient oxidative annulation of alkynes furnished diversely substituted pyran[2,3,4-de]chromene-2-one derivatives and related polycycles in moderate to high yield. The reaction is catalyzed by nontoxic, air-stable, and inexpensive Cp*Co(CO)I2catalyst. The hydroxyl moiety at the substrate acts as the directing group for the C–H bond activation.

Introduction:P-selectin is a cell adhesion molecule that contributes to vaso-occlusive crises (VOCs) in sickle cell disease (SCD). Inclacumab is a recombinant, fully human, immunoglobulin G4 monoclonal antibody that selectively binds to P-selectin to prevent binding with P-selectin glycoprotein ligand-1. Inclacumab was previously evaluated by Roche in clinical trials with healthy participants and patients with cardiovascular disease and is now being developed as a potential treatment to reduce the frequency of VOCs in individuals with SCD. Changes in the manufacturing of inclacumab have resulted in 3 formulations/drug materials: Roche v0.1, Roche v0.2, and Global Blood Therapeutics (GBT). GBT-manufactured inclacumab utilizes a similar formulation and the same cell line as Roche v0.2 (Roche v0.1 utilizes a different cell line), and analytical and nonclinical comparability between Roche v0.2 and GBT inclacumab have been demonstrated (Mihaila et al. Expert Opin Biol Ther 2022). Here we report results from a population pharmacokinetic (PopPK) model developed to compare the pharmacokinetics (PK) of different formulations using data from 4 phase 1 clinical studies in healthy participants administered Roche v0.1, Roche v0.2, or GBT inclacumab. The objectives were to develop a PopPK model to describe inclacumab PK in healthy adult participants and to quantify potential differences in inclacumab PK associated with different formulations/drug materials.

An operationally simple mechanochemical reaction between iminoiodinanes with numerous cyclic 2°‐amines such as morpholine, piperidine, pyrrolidine, thiomorpholine, N‐Boc diazepine and N‐Boc piperazine has been reported to afford N‐sulfonyl amidines in moderate to excellent yield. The N‐sulfonyl transfer reaction happens in a ball mill apparatus (RETSCH 400™) with three 5 mm stainless steel (ss) balls in a 5 mL stainless steel (ss) reaction jar with 2‐methyl tetrahydrofuran as liquid assisted grinding auxiliary (LAG). This metal catalyst‐base free synthesis with minimal solvents (as LAGs) demonstrated an efficient N‐sulfonyl transfer reaction from iminoiodinanes. N‐sulfonyl amidines are ubiquitous building blocks present in natural products and drug intermediates. Control experiments and computational studies based on density functional theory (DFT) calculations were performed to gain deeper insight into the mechanism. The mechanochemical synthesis of diverse sulfonyl amidines from iminoiodinanes is an efficient and environmentally friendly approach to access a wide range of valuable compounds.

Due to their low-temperature processing properties and inherent mechanical flexibility, conjugated polymer field-effect transistors (FETs) are promising candidates for enabling flexible electronic circuits and displays. Much progress has been made on materials performance; however, there remain significant concerns about operational and environmental stability, particularly in the context of applications that require a very high level of threshold voltage stability, such as active-matrix addressing of organic light-emitting diode displays. Here, we investigate the physical mechanisms behind operational and environmental degradation of high-mobility, p-type polymer FETs and demonstrate an effective route to improve device stability. We show that water incorporated in nanometre-sized voids within the polymer microstructure is the key factor in charge trapping and device degradation. By inserting molecular additives that displace water from these voids, it is possible to increase the stability as well as uniformity to a high level sufficient for demanding industrial applications.

Donor–acceptor organic solar cells often show high quantum yields for charge collection, but relatively low open-circuit voltages (VOC) limit power conversion efficiencies to around 12%. We report here the behavior of a system, PIPCP:PC61BM, that exhibits very low electronic disorder (Urbach energy less than 27 meV), very high carrier mobilities in the blend (field-effect mobility for holes >10–2cm2V–1s–1), and a very low driving energy for initial charge separation (50 meV). These characteristics should give excellent performance, and indeed, the VOCis high relative to the donor energy gap. However, we find the overall performance is limited by recombination, with formation of lower-lying triplet excitons on the donor accounting for 90% of the recombination. We find this is a bimolecular process that happens on time scales as short as 100 ps. Thus, although the absence of disorder and the associated high carrier mobility speeds up charge diffusion and extraction at the electrodes, which we measure as early as 1 ns, this also speeds up the recombination channel, giving overall a modest quantum yield of around 60%. We discuss strategies to remove the triplet exciton recombination channel.

We propose a new methodology for the first-principles description of the electronic properties relevant for charge transport in organic molecular crystals. This methodology, which is based on the combination of a nonempirical, optimally tuned range-separated hybrid functional with the polarizable continuum model, is applied to a series of eight representative molecular semiconductor crystals. We show that it provides ionization energies, electron affinities, and transport gaps in very good agreement with experimental values, as well as with the results of many-body perturbation theory within the GW approximation at a fraction of the computational costs. Hence, this approach represents an easily applicable and computationally efficient tool to estimate the gas-to-crystal phase shifts of the frontier-orbital quasiparticle energies in organic electronic materials.

Long polymethines are well-known experimentally to symmetry-break, which dramatically modifies their linear and nonlinear optical properties. Computational modeling could be very useful to provide insight into the symmetry-breaking process, which is not readily available experimentally; however, accurately predicting the crossover point from symmetric to symmetry-broken structures has proven challenging. Here, we benchmark the accuracy of several density functional theory approaches relative to CCSD(T) geometries. In particular, we compare analogous hybrid and long-range-corrected (LRC) functionals to clearly show the influence of the functional exchange term. Although both hybrid and LRC functionals can be tuned to reproduce the CCSD(T) geometries, the LRC functionals are better performing at reproducing the geometry evolution with chain length and provide a finite upper limit for the gas-phase crossover point; these methods also provide good agreement with the experimental crossover points for more complex polymethines in polar solvents. Using an approach based on LRC functionals, a reduction in the crossover length is found with increasing medium dielectric constant, which is related to localization of the excess charge on the end groups. Symmetry breaking is associated with the appearance of an imaginary frequency of b2symmetry involving a large change in the degree of bond-length alternation. Examination of the IR spectra shows that short, isolated streptocyanines have a mode at ∼1200 cm–1involving a large change in bond-length alternation; as the polymethine length or the medium dielectric increases, the frequency of this mode decreases before becoming imaginary at the crossover point.

We present a versatile approach for tuning the surface functionality of an atomically precise 25 atom gold cluster using specific host–guest interactions between β-cyclodextrin (CD) and the ligand anchored on the cluster. The supramolecular interaction between the Au25cluster protected by 4-(t-butyl)benzyl mercaptan, labeled Au25SBB18, and CD yielding Au25SBB18∩CDn(n= 1, 2, 3, and 4) has been probed experimentally using various spectroscopic techniques and was further analyzed by density functional theory calculations and molecular modeling. The viability of our method in modifying the properties of differently functionalized Au25clusters is demonstrated. Besides modifying their optoelectronic properties, the CD moieties present on the cluster surface provide enhanced stability and optical responses which are crucial in view of the potential applications of these systems. Here, the CD molecules act as an umbrella which protects the fragile cluster core from the direct interaction with many destabilizing agents such as metal ions, ligands, and so on. Apart from the inherent biocompatibility of the CD-protected Au clusters, additional capabilities acquired by the supramolecular functionalization make such modified clusters preferred materials for applications, including those in biology.

ABSTRACTTo further optimize the voriconazole dosing in the pediatric population, a population pharmacokinetic analysis was conducted on pooled data from 112 immunocompromised children (2 to <12 years), 26 immunocompromised adolescents (12 to <17 years), and 35 healthy adults. Different maintenance doses (i.e., 3, 4, 6, 7, and 8 mg/kg of body weight intravenously [i.v.] every 12 h [q12h]; 4 mg/kg, 6 mg/kg, and 200 mg orally q12h) were evaluated in these children. The adult dosing regimens (6 mg/kg i.v. q12h on day 1, followed by 4 mg/kg i.v. q12h, and 300 mg orally q12h) were evaluated in the adolescents. A two-compartment model with first-order absorption and mixed linear and nonlinear (Michaelis-Menten) elimination adequately described the voriconazole data. Larger interindividual variability was observed in pediatric subjects than in adults. Deterministic simulations based on individual parameter estimates from the final model revealed the following. The predicted total exposure (area under the concentration-time curve from 0 to 12 h [AUC0-12]) in children following a 9-mg/kg i.v. loading dose was comparable to that in adults following a 6-mg/kg i.v. loading dose. The predicted AUC0-12s in children following 4 and 8 mg/kg i.v. q12h were comparable to those in adults following 3 and 4 mg/kg i.v. q12h, respectively. The predicted AUC0-12in children following 9 mg/kg (maximum, 350 mg) orally q12h was comparable to that in adults following 200 mg orally q12h. To achieve voriconazole exposures comparable to those of adults, dosing in 12- to 14-year-old adolescents depends on their weight: they should be dosed like children if their weight is <50 kg and dosed like adults if their weight is ≥50 kg. Other adolescents should be dosed like adults.

Compost water extracts (compost teas) are gaining popularity among organic growers, largely because of their disease suppressive activity when applied to foliage or soil. Production methods often include addition of supplemental constituents, particularly molasses, to stimulate plant-beneficial microbial populations. We have found that molasses amendments also favor regrowth of human pathogenic bacteria, raising public health concerns about potential contamination of treated crops, particularly produce intended for fresh consumption. Using disease outbreak strains marked with green fluorescent protein(GFP) and spontaneous antibiotic-resistance, we found that regrowth of Salmonella entericaserovar Thompson and Escherichia coliO157:H7 was positively correlated with molasses concentration. For Salmonella, regrowth was also dependent on the type of starter compost material used. Salmonellapopulations increased from 1 at time 0 to over 1000 CFU ml−1in dairy manure compost tea with 1% molasses, and from 1 at time 0 to over 350,000 CFU ml−1in chicken manure compost tea by 72 h. E. colipopulations increased from 1 at time 0 to approximately 1000 CFU ml−1in both types of tea by 72 h. Pathogen regrowth did not occur when molasses was eliminated or kept to 0.2%.