A Structural Analysis of the FDA Green Book-Approved Veterinary Drugs and Roles in Human Medicine

Machine learning powered CN-coordinated cobalt nanoparticles embedded cellulosic nanofibers to assess meat quality via clenbuterol monitoring

The World Anti-Doping Agency (WADA) has prohibited the use of clenbuterol (CLN) because it induces anabolic muscle growth while potentially causing adverse effects such as palpitations, anxiety, and muscle tremors. Thus, it is vital to assess meat quality because, athletes might have positive test for CLN even after consuming very low quantity of CLN contaminated meat. Numerous materials applied for CLN monitoring faced potential challenges like sluggish ion transport, non-uniform ion/molecule movement, and inadequate electrode surface binding. To overcome these shortcomings, herein we engineered bimetallic zeolitic imidazole framework (BM-ZIF) derived N-doped porous carbon embedded Co nanoparticles (CN-CoNPs), dispersed on conductive cellulose acetate-polyaniline (CP) electrospun nanofibers for sensitive electrochemical monitoring of CLN. Interestingly, the smartly designed CN-CoNPs wrapped CP (CN-CoNPs-CP) electrospun nanofibers offers rapid diffusion of CLN molecules to the sensing interface through amine and imine groups of CP, thus minimizing the inhomogeneous ion transportation and inadequate electrode surface binding. Additionally, to synchronize experiments, machine learning (ML) algorithms were applied to optimize, predict, and validate voltametric current responses. The ML-trained sensor demonstrated high selectivity, even amidst interfering substances, with notable sensitivity (4.7527 μA/μM/cm2), a broad linear range (0.002-8 μM), and a low limit of detection (1.14 nM). Furthermore, the electrode exhibited robust stability, retaining 98.07% of its initial current over a 12-h period. This ML-powered sensing approach was successfully employed to evaluate meat quality in terms of CLN level. To the best of our knowledge, this is the first study of using ML powered system for electrochemical sensing of CLN.

Recent developments in the enzymatic modifications of steroid scaffolds

Steroids are an important family of bioactive compounds. Steroid drugs are renowned for their multifaceted pharmacological activities and are the second-largest category in the global pharmaceutical market. Recent developments in biocatalysis and biosynthesis have led to the increased use of enzymes to enhance the selectivity, efficiency, and sustainability for diverse modifications of steroids. This review discusses the advancements achieved over the past five years in the enzymatic modifications of steroid scaffolds, focusing on enzymatic hydroxylation, reduction, dehydrogenation, cascade reactions, and other modifications for future research on the synthesis of novel steroid compounds and related drugs, and new therapeutic possibilities.

Enabling a novel solvent method on Albendazole solid dispersion to improve the in vivo bioavailability

Albendazole, a vital medication endorsed by the World Health Organization for combating parasitic infections, encounters a challenge stemming from its low solubility, significantly impeding absorption and bioavailability. Albendazole has near-insolubility in most organic solvents, so the solid dispersions of albendazole were predominantly using the fusion method. However, the solvent method could offer the advantage of achieving molecular-level mixing homogeneity. In this investigation, we incorporated the pH adjustment to prepare albendazole solid dispersion using a solvent method, which utilizes trace amounts of HCl in methanol, yielding notably enhanced albendazole solubility. Subsequently, carriers such as PEG6000/Poloxamer 188 (PEG: polyethylene glycol) and PVP K30/Poloxamer 188 (PVP: polyvinylpyrrolidone) were employed to create albendazole solid dispersions. Comprehensive characterization through dissolution rate analysis, PXRD (Powder X-ray diffraction), SEM (Scanning electron microscopy), DSC (differential scanning calorimetry), and pharmacokinetic (PK) studies in mice and rats was conducted. The findings indicate that the solid dispersion effectively transforms the crystalline state of albendazole into an amorphous state, resulting in significantly enhanced in vivo absorption and a 5.9-fold increase in exposure. Besides, the exposure increased 1.64 times of commercial albendazole tablets. Notably, PEG6000/Poloxamer 188 and PVP K30/Poloxamer 188 solid dispersions exhibited superior dissolution rates and pharmacokinetic profiles compared to commercially available albendazole tablets.

Do Pharmaceuticals in the Environment Pose a Risk to Wildlife?

The vast majority of knowledge related to the question "To what extent do pharmaceuticals in the environment pose a risk to wildlife?" stems from the Asian vulture crisis (>99% decline of some species of Old World vultures on the Indian subcontinent related to the veterinary use of the nonsteroidal anti-inflammatory drug [NSAID] diclofenac). The hazard of diclofenac and other NSAIDs (carprofen, flunixin, ketoprofen, nimesulide, phenylbutazone) to vultures and other avian species has since been demonstrated; indeed, only meloxicam and tolfenamic acid have been found to be vulture-safe. Since diclofenac was approved for veterinary use in Spain and Italy in 2013 (home to ~95% of vultures in Europe), the risk of NSAIDs to vultures in these countries has become one of the principal concerns related to pharmaceuticals and wildlife. Many of the other bodies of work on pharmaceutical exposure, hazard and risk to wildlife also relate to adverse effects in birds (e.g., poisoning of scavenging birds in North America and Europe from animal carcasses containing pentobarbital, secondary and even tertiary poisoning of birds exposed to pesticides used in veterinary medicine as cattle dips, migratory birds as a vector for the transfer of antimicrobial and antifungal resistance). Although there is some research related to endocrine disruption in reptiles and potential exposure of aerial insectivores, there remain numerous knowledge gaps for risk posed by pharmaceuticals to amphibians, reptiles, and mammals. Developing noninvasive sampling techniques and new approach methodologies (e.g., genomic, in vitro, in silico, in ovo) is important if we are to bridge the current knowledge gaps without extensive vertebrate testing. Environ Toxicol Chem 2024;43:595-610. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Photoinduced α-Aminoalkylation of Sulfonylarenes with Alkylamines

α-Aminoalkylation of sulfonylarenes with alkylamines was found to be induced by photoirradiation. Here various types of alkylamines, such as trialkylamines, dialkylamines, N,N-dialkylanilines and N-alkylanilines as well as sulfonylarenes containing an azole, azine, heterole or benzene ring are available. The reaction proceeds through a homolytic aromatic substitution (HAS) process consisting of addition of an α-aminoalkyl radical to a sulfonylarene and elimination of the sulfonyl radical to give the α-arylalkylamine, where photoirradiation is considered to induce homolysis of sulfonylarenes leading to the generation of α-aminoalkyl radicals that make a radical chain operative.

Photoelectrochemical aptasensing of lincomycin based on a AgI-carboxylated multiwalled carbon nanotubes-BiOI Z-scheme heterojunction

Lincomycin (LIN) is a common antibiotic that is widely used in animal husbandry and other fields, and the residual problem caused by its abuse has attracted widespread attention. Herein, a novel AgI-carboxylated multiwalled carbon nanotubes (cMWCNT)-BiOI Z-scheme heterojunction material was synthesized via a one-pot hydrothermal method, modified on a fluorine-doped tin oxide (FTO) electrode surface, and used for detecting LIN. The photocurrent on the AgI-cMWCNT-BiOI/FTO photoelectrode is 4.6 times that on the control AgI-BiOI/FTO photoelectrode. An amino-functionalized LIN aptamer was fixed on the AgI-cMWCNT-BiOI/FTO photoelectrode by the cross-linking reaction between chitosan and glutaraldehyde, and then Ru(NH3)63+ was electrostatically attached to the LIN aptamer to increase the photocurrent response to the LIN binding. When LIN binds competitively with Ru(NH3)63+ to the aptamer, the photocurrent signal can be quantitatively decreased. Under optimized conditions, the anodic photocurrent at 0 V vs KCl-saturated calomel electrode in 0.1 M phosphate buffer (pH 7.0) containing 0.100 M ascorbic acid was linear with the common logarithm of LIN concentration from 10.0 pM to 500 nM, with a limit of detection of 2.8 pM (S/N = 3). Satisfactory recovery results were obtained in the analysis of cow milk samples.

Electrochemical Direct α-Arylation of Alkylamines with Sulfonylarenes

The electrochemical α-arylation of alkylamines with sulfonylarenes has been developed. Here, diverse trialkylamines and aryl(dimethyl)amines are applicable to the α-arylation with sulfonylarenes having an azole, azine, and benzene nucleus. The α-arylation was scaled up using an electrolysis flow cell. Mechanistic studies show that anodic oxidation of an alkylamine with a sulfinate as a mediator followed by deprotonation gives an α-aminoalkyl radical, which undergoes homolytic aromatic substitution (HAS) on a sulfonylarene to give the corresponding α-arylalkylamine.

Visible-light-induced nickel-catalyzed α-hydroxytrifluoroethylation of alkyl carboxylic acids: Access to trifluoromethyl alkyl acyloins

A visible-light-induced nickel-catalyzed cross coupling of alkyl carboxylic acids with N-trifluoroethoxyphthalimide is described. Under purple light irradiation, an α-hydroxytrifluoroethyl radical generated from a photoactive electron donor-acceptor complex between Hantzsch ester and N-trifluoroethoxyphthalimide was subsequently engaged in a nickel-catalyzed coupling reaction with in situ-activated alkyl carboxylic acids. This convenient protocol does not require photocatalysts and metal reductants, providing a straightforward and efficient access to trifluoromethyl alkyl acyloins in good yields with broad substrate compatibility. The complex bioactive molecules were also compatible with this catalytic system to afford the corresponding products.

Total Synthesis of abeo-Steroids via Cycloaddition Strategy

ConspectusSteroids continue to play a significant role in organic chemistry, medicinal chemistry, and drug discovery due to their important biological activities and diverse intriguing structures. Although synthetic organic chemists have successfully constructed and elaborated the classical [6-6-6-5] tetracyclic steroid skeleton for nearly a century, synthesis of the unusual rearranged steroids, particularly abeo-steroids with a medium-sized ring, remains a challenge in the synthetic community. Furthermore, the structures of abeo-steroids are complex and diverse, containing a seven-membered ring embedded in the fused or bridged A/B ring system and possessing numerous stereogenic centers. Besides their structural complexity, various abeo-steroids have shown remarkable biological activities. However, the relative scarcity of abeo-steroids in natural sources has impeded the systematic evaluation of their biological activities. In addition, direct strategies to build the core structures of abeo-steroids are very rare, partially because of the high ring-strain energies of their rearranged A/B ring systems. Therefore, the development of direct and efficient synthetic approaches to these complex molecules is highly desired.Our long-standing interest in the total synthesis of abeo-steroids and the development of new cycloaddition reactions for streamlining complex molecule synthesis have led us to develop a series of unique and powerful intramolecular cycloaddition strategies to access a diverse array of highly strained abeo-steroids. These strategies include Ru-catalyzed [5 + 2] cycloaddition, acid-promoted type I [5 + 2] cycloaddition, Rh-catalyzed [2 + 2 + 1] cycloaddition, and type II [5 + 2] cycloaddition. Since 2018, we have accomplished the first total syntheses of five synthetically challenging abeo-steroids, i.e., bufogargarizins A and B, phomarol, bufospirostenin A, and cyclocitrinol, thus facilitating the evaluation of their pharmacological potentials. In this Account, we summarize our laboratory's systematic efforts in the total synthesis of these abeo-steroids via cycloaddition strategies. We highlight the efficiency and versatility of each cycloaddition strategy for constructing structurally complex abeo-steroid cores by forming the A/B ring system. The evolution of each strategy and key lessons learned from the synthetic journey are also discussed. We believe that our unique perspective in this field will promote advances in the total synthesis of abeo- and related steroids.

meta-Selective C-H arylation of phenols via regiodiversion of electrophilic aromatic substitution

Electrophilic aromatic substitution is among the most widely used mechanistic manifolds in organic chemistry. Access to certain substitution patterns is, however, precluded by intrinsic and immutable substituent effects that ultimately restrict the diversity of the benzenoid chemical space. Here we demonstrate that the established regioselectivity of electrophilic aromatic substitution can be overcome simply by diverting the key σ-complex intermediate towards otherwise inaccessible substitution products. This 'regiodiversion' strategy is realized through the development of a general and concise method for the meta-selective C-H arylation of sterically congested phenols. Consisting of a Bi(V)-mediated electrophilic arylation and a subsequent aryl migration/rearomatization, our process is orthogonal to conventional C-H activation and cross-coupling approaches, and does not require prefunctionalization of the substrate. Mechanistically informed applications in synthesis showcase its utility as a versatile and enabling route to highly functionalized, contiguously substituted aromatic building blocks that defy synthesis via existing methods.

DrugCentral 2023 extends human clinical data and integrates veterinary drugs

DrugCentral monitors new drug approvals and standardizes drug information. The current update contains 285 drugs (131 for human use). New additions include: (i) the integration of veterinary drugs (154 for animal use only), (ii) the addition of 66 documented off-label uses and iii) the identification of adverse drug events from pharmacovigilance data for pediatric and geriatric patients. Additional enhancements include chemical substructure searching using SMILES and 'Target Cards' based on UniProt accession codes. Statistics of interests include the following: (i) 60% of the covered drugs are on-market drugs with expired patent and exclusivity coverage, 17% are off-market, and 23% are on-market drugs with active patents and exclusivity coverage; (ii) 59% of the drugs are oral, 33% are parenteral and 18% topical, at the level of the active ingredients; (iii) only 3% of all drugs are for animal use only; however, 61% of the veterinary drugs are also approved for human use; (iv) dogs, cats and horses are by far the most represented target species for veterinary drugs; (v) the physicochemical property profile of animal drugs is very similar to that of human drugs. Use cases include azaperone, the only sedative approved for swine, and ruxolitinib, a Janus kinase inhibitor.

Electrochemical Synthesis of gem-Difluoro- and γ-Fluoro-Allyl Boronates and Silanes

The electrochemical synthesis of fluorinated allyl silanes and boronates was disclosed. The addition of electrogenerated boryl or silyl radicals onto many α-trifluoromethyl or α-difluoromethylstyrenes in an undivided cell allowed the formation of a large panel of synthetically useful gem-difluoro and γ-fluoroallyl boronates and silanes (64 examples, from 31 % to 95 % yield). In addition, a scale up of the reactions under continuous flow was showcased using an electrochemical reactor with promising volumetric productivity (688 g.L-1 .h-1 and 496 g.L-1 .h-1 ). Moreover, the synthetic utility of these building blocks was highlighted through versatile transformations. Finally, plausible reaction mechanisms were suggested to explain the formation of the products.

Zambrano-Rodríguez P. The Use of Peptides in Veterinary Serodiagnosis of Infectious Diseases: A Review

Peptides constitute an alternative and interesting option to develop treatments, vaccines, and diagnostic tools as they demonstrate their scope in several health aspects; as proof of this, commercial peptides for humans and animals are available on the market and used daily. This review aimed to know the role of peptides in the field of veterinary diagnosis, and include peptide-based enzyme-linked immunosorbent assay (pELISA), lateral flow devices, and peptide latex agglutination tests that have been developed to detect several pathogens including viruses and bacteria of health and production relevance in domestic animals. Studies in cattle, small ruminants, dogs, cats, poultry, horses, and even aquatic organisms were reviewed. Different studies showed good levels of sensitivity and specificity against their target, moreover, comparisons with commercial kits and official tests were performed which allowed appraising their performance. Chemical synthesis, recombinant DNA technology, and enzymatic synthesis were reviewed as well as their advantages and drawbacks. In addition, we discussed the intrinsic limitations such as the small size or affinity to polystyrene membrane and mention several strategies to overcome these problems. The use of peptides will increase in the coming years and their utility for diagnostic purposes in animals must be evaluated.

1,2-Diamines as the Amine Sources in Amidation and Rhodium-Catalyzed Asymmetric Reductive Amination Cascade Reactions

The sturdy chelation of 1,2-diamines and transition-metals would retard or even interrupt the routine catalytic cycles. In the amidation and asymmetric reductive amination (ARA) cascade reactions of diamines and ketoesters, we deployed sets of additives to ensure a smooth transformation catalyzed by the complexes of rhodium and versatile and highly modular phosphoramidite-phosphine ligands. The tunability of the ligands was fully exploited to accommodate various diamines and α-ketoesters for the efficient synthesis of chiral 3,4-dihydroquinoxalinones.

Phenols in Pharmaceuticals: Analysis of a Recurring Motif

Phenols and phenolic ethers are significant scaffolds recurring both in nature and among approved small-molecule pharmaceuticals. This compendium presents the first comprehensive compilation and analysis of the structures of U.S. FDA-approved molecules containing phenol or phenolic ether fragments. This dataset comprises 371 structures, which are strongly represented by natural products. A total of 55 of the compounds described here are on the World Health Organization's list of essential medicines. Structural analysis reveals significant differences in the physicochemical properties imparted by phenols versus phenol ethers, each having benefits and drawbacks for drug developability. Despite trends over the past decade to increase the fraction of sp³ centers in drug leads, thereby "escaping flatland", phenols and phenolic ethers are represented in 62% of small-molecule drugs approved in 2020, suggesting that this aromatic moiety holds a special place in drugs and natural products.

Catalytic Enantioselective Access to Dihydroquinoxalinones via Formal α-Halo Acyl Halide Synthon in One Pot

An enantioselective one-pot catalytic strategy to dihydroquinoxalinones, featuring novel 1-phenylsulfonyl-1-cyano enantioenriched epoxides as masked α-halo acyl halide synthons, followed by a domino ring-opening cyclization (DROC), is documented. A popular quinine-derived urea served as the catalyst in two out of the three steps performed in the same solvent using commercially available aldehydes, (phenylsulfonyl)acetonitrile, cumyl hydroperoxide and 1,2-phenylendiamines. Medicinally relevant 3-aryl/alkyl-substituted heterocycles are isolated in generally good to high overall yield and high enantioselectivity (up to 99 % ee). A rare example of excellent reusability of an organocatalyst at higher scale, subjected to oxidative conditions, is demonstrated. Mechanistically, labile α-ketosulfone has been detected as the intermediate involved in the DROC process. Theoretical calculations on the key epoxidation step rationalize the observed stereocontrol, highlighting the important role played by the sulfone group.

What's in a Name? Drug Nomenclature and Medicinal Chemistry Trends using INN Publications

The World Health Organization assigns international nonproprietary names (INN), also known as common names, to compounds upon request from drug developers. Structures of INNs are publicly available and represent a source, albeit underused, to understand trends in drug research and development. Here, we explain how a common drug name is composed and analyze chemical entities from 2000 to 2021. In the analysis, we describe some changes that intertwine chemical structure, newer therapeutic targets (e.g., kinases), including a significant increase in the use of fluorine and of heterocycles, and some other evolutionary modifications, such as the progressive increase in molecular weight. Alongside these, small signs of change can be spotted, such as the rise in spirocyclic scaffolds and small rings and the emergence of unconventional structural moieties that might forecast the future to come.