In Vivo and In Vitro Metabolic Fate and Urinary Detectability of Five Deschloroketamine Derivatives Studied by Means of Hyphenated Mass Spectrometry.

Ketamine derivatives such as deschloroketamine and deschloro-N-ethyl-ketamine show dissociative and psychoactive properties and their abuse as new psychoactive substances (NPSs) has been reported. Though some information is available on the biotransformation of dissociative NPSs, data on deschloro-N-cyclopropyl-ketamine deschloro-N-isopropyl-ketamine and deschloro-N-propyl-ketamine concerning their biotransformation and, thus, urinary detectability are not available. The aims of the presented work were to study the in vivo phase I and II metabolism; in vitro phase I metabolism, using pooled human liver microsomes (pHLMs); and detectability, within a standard urine screening approach (SUSA), of five deschloroketamine derivatives. Metabolism studies were conducted by collecting urine samples from male Wistar rats over a period of 24 h after their administration at 2 mg/kg body weight. The samples were analyzed using liquid chromatography high-resolution tandem mass spectrometry (LC-HRMS/MS) and gas chromatography-mass spectrometry (GC-MS). The compounds were mainly metabolized by N-dealkylation, hydroxylation, multiple oxidations, and combinations of these metabolic reactions, as well as glucuronidation and N-acetylation. In total, 29 phase I and 10 phase II metabolites were detected. For the LC-HRMS/MS SUSA, compound-specific metabolites were identified, and suitable screening targets could be recommended and confirmed in pHLMs for all derivatives except for deschloro-N-cyclopropyl-ketamine. Using the GC-MS-based SUSA approach, only non-specific acetylated N-dealkylation metabolites could be detected.

Nonintuitive Immunogenicity and Plasticity of Alpha-Synuclein Conformers: A Paradigm for Smart Delivery of Neuro-Immunotherapeutics.

Despite the extensive research successes and continuous developments in modern medicine in terms of diagnosis, prevention, and treatment, the lack of clinically useful disease-modifying drugs or immunotherapeutic agents that can successfully treat or prevent neurodegenerative diseases is an ongoing challenge. To date, only one of the 244 drugs in clinical trials for the treatment of neurodegenerative diseases has been approved in the past decade, indicating a failure rate of 99.6%. In corollary, the approved monoclonal antibody did not demonstrate significant cognitive benefits. Thus, the prevalence of neurodegenerative diseases is increasing rapidly. Therefore, there is an urgent need for creative approaches to identifying and testing biomarkers for better diagnosis, prevention, and disease-modifying strategies for the treatment of neurodegenerative diseases. Overexpression of the endogenous α-synuclein has been identified as the driving force for the formation of the pathogenic α-synuclein (α-Syn) conformers, resulting in neuroinflammation, hypersensitivity, endogenous homeostatic responses, oxidative dysfunction, and degeneration of dopaminergic neurons in Parkinson's disease (PD). However, the conformational plasticity of α-Syn proffers that a certain level of α-Syn is essential for the survival of neurons. Thus, it exerts both neuroprotective and neurotoxic (regulatory) functions on neighboring neuronal cells. Furthermore, the aberrant metastable α-Syn conformers may be subtle and difficult to detect but may trigger cellular and molecular events including immune responses. It is well documented in literature that the misfolded α-Syn and its conformers that are released into the extracellular space from damaged or dead neurons trigger the innate and adaptive immune responses in PD. Thus, in this review, we discuss the nonintuitive plasticity and immunogenicity of the α-Syn conformers in the brain immune cells and their physiological and pathological consequences on the neuroimmune responses including neuroinflammation, homeostatic remodeling, and cell-specific interactions that promote neuroprotection in PD. We also critically reviewed the novel strategies for immunotherapeutic delivery interventions in PD pathogenesis including immunotherapeutic targets and potential nanoparticle-based smart drug delivery systems. It is envisioned that a greater understanding of the nonintuitive immunogenicity of aberrant α-Syn conformers in the brain's microenvironment would provide a platform for identifying valid therapeutic targets and developing smart brain delivery systems for clinically effective disease-modifying immunotherapeutics that can aid in the prevention and treatment of PD in the future.

Can a best practice advisory improve anticoagulation prescribing to reduce stroke risk in patients with atrial fibrillation?

BACKGROUND: Atrial fibrillation (AF) is the most common cardiac rhythm disorder and a risk factor for stroke. Randomized trials have demonstrated that anticoagulation can reduce strokes in AF patients. Yet, widespread underutilization of this therapy continues. To address this practice gap, we designed a study to implement and evaluate the effectiveness of a best practice advisory (BPA) for an Atrial Fibrillation Decision Support Tool (AFDST) embedded within our electronic health record. METHODS: Our intervention is provider-facing, focused on decision support. Clinical setting is ambulatory patients being seen by primary care physicians. We prospectively enrolled 608 patients in our health system who are currently receiving less than optimal anticoagulation therapy as determined by the AFDST and randomized them to one of two arms - 1) usual care, in which the AFDST is available for use; or 2) addition of a BPA to the AFDST notifying clinicians that their patient stands to gain significant benefit from a change in current therapy. Primary outcome was effectiveness of the BPA measured by change to "appropriate thromboprophylaxis" based on the AFDST recommendation at 3 months post-enrollment. Secondary endpoints included Reach and Adoption from the RE-AIM (Reach, Effectiveness, Adoption, Implementation, & Maintenance) framework for implementation studies. RESULTS: Among 562 patients with a minimum follow-up of 3 months, addition of a BPA to the AFDST resulted in significant improvement in anticoagulation therapy, 5 % (12/248) versus 11 % (33/314) p = 0.02, odds ratio 2.31 (95 % CI, 1.17-4.87). CONCLUSIONS: A BPA added to an AF decision support tool improved anticoagulation therapy among AF patients in a primary care academic health system setting.

Attenuation of Vanadium-Induced Neurotoxicity in Rat Hippocampal Slices (In Vitro) and Mice (In Vivo) by ZA-II-05, a Novel NMDA-Receptor Antagonist.

Exposure to heavy metals, such as vanadium, poses an ongoing environmental and health threat, heightening the risk of neurodegenerative disorders. While several compounds have shown promise in mitigating vanadium toxicity, their efficacy is limited. Effective strategies involve targeting specific subunits of the NMDA receptor, a glutamate receptor linked to neurodegenerative conditions. The potential neuroprotective effects of ZA-II-05, an NMDA receptor antagonist, against vanadium-induced neurotoxicity were explored in this study. Organotypic rat hippocampal slices, and live mice, were used as models to comprehensively evaluate the compound's impact. Targeted in vivo fluorescence analyses of the hippocampal slices using propidium iodide as a marker for cell death was utilized. The in vivo study involved five dams, each with eight pups, which were randomly assigned to five experimental groups (n = 8 pups). After administering treatments intraperitoneally over six months, various brain regions were assessed for neuropathologies using different immunohistochemical markers. High fluorescence intensity was observed in the hippocampal slices treated with vanadium, signifying cell death. Vanadium-exposed mice exhibited demyelination, microgliosis, and neuronal cell loss. Significantly, treatment with ZA-II-05 resulted in reduced cellular death in the rat hippocampal slices and preserved cellular integrity and morphological architecture in different anatomical regions, suggesting its potential in countering vanadium-induced neurotoxicity.

GluN2A and GluN2B N-Methyl-D-Aspartate Receptor (NMDARs) Subunits: Their Roles and Therapeutic Antagonists in Neurological Diseases.

N-methyl-D-aspartate receptors (NMDARs) are ion channels that respond to the neurotransmitter glutamate, playing a crucial role in the permeability of calcium ions and excitatory neurotransmission in the central nervous system (CNS). Composed of various subunits, NMDARs are predominantly formed by two obligatory GluN1 subunits (with eight splice variants) along with regulatory subunits GluN2 (GluN2A-2D) and GluN3 (GluN3A-B). They are widely distributed throughout the CNS and are involved in essential functions such as synaptic transmission, learning, memory, plasticity, and excitotoxicity. The presence of GluN2A and GluN2B subunits is particularly important for cognitive processes and has been strongly implicated in neurodegenerative diseases like Parkinson's disease and Alzheimer's disease. Understanding the roles of GluN2A and GluN2B NMDARs in neuropathologies provides valuable insights into the underlying causes and complexities of major nervous system disorders. This knowledge is vital for the development of selective antagonists targeting GluN2A and GluN2B subunits using pharmacological and molecular methods. Such antagonists represent a promising class of NMDA receptor inhibitors that have the potential to be developed into neuroprotective drugs with optimal therapeutic profiles.

Implementing a Health Utility Assessment Platform to Acquire Health Utilities in a Hemodialysis Outpatient Setting: Feasibility Study.

BACKGROUND: Patients with end-stage kidney disease (ESKD) wait roughly 4 years for a kidney transplant. A potential way to reduce wait times is using hepatitis C virus (HCV)-viremic kidneys. OBJECTIVE: As preparation for developing a shared decision-making tool to assist patients with ESKD with the decision to accept an HCV-viremic kidney transplant, our initial goal was to assess the feasibility of using The Gambler II, a health utility assessment tool, in an ambulatory dialysis clinic setting. Our secondary goals were to collect health utilities for patients with ESKD and to explore whether the use of race-matched versus race-mismatched exemplars impacted the knowledge gained during the assessment process. METHODS: We used The Gambler II to elicit utilities for the following ESKD-related health states: hemodialysis, kidney transplant with HCV-unexposed kidney, and transplantation with HCV-viremic kidney. We created race exemplar video clips describing these health states and randomly assigned patients into the race-matched or race-mismatched video arms. We obtained utilities for these 3 health states from each patient, and we evaluated knowledge about ESKD and HCV-associated health conditions with pre- and postintervention knowledge assessments. RESULTS: A total of 63 patients with hemodialysis from 4 outpatient Dialysis Center Inc sites completed the study. Mean adjusted standard gamble utilities for hemodialysis, transplant with HCV-unexposed kidney, and transplantation with HCV-viremic kidney were 82.5, 89, and 75.5, respectively. General group knowledge assessment scores improved by 10 points (P<.05) following utility assessment process. The use of race-matched exemplars had little effect on the results of the knowledge assessment of patients. CONCLUSIONS: Using The Gambler II to collect utilities for patients with ESKD in an ambulatory dialysis clinic setting proved feasible. In addition, educational information about health states provided as part of the utility assessment process tool improved patients' knowledge and understanding about ESKD-related health states and implications of organ transplantation with HCV-viremic kidneys. A wide variation in patient health state utilities reinforces the importance of incorporating patients' preferences into decisions regarding use of HCV-viremic kidneys for transplantation.

Electronic health record-embedded decision support to reduce stroke risk in patients with atrial fibrillation - Study protocol.

BACKGROUND: Atrial fibrillation (AF) is the most common significant cardiac rhythm disorder and is a powerful common risk factor for stroke. Randomized trials have demonstrated that anticoagulation can reduce the risk of stroke in patients with AF. Yet, there continues to be widespread underutilization of this therapy. To address this practice gap locally and improve efforts to reduce the risk of stroke for patients with AF in our health system, we have designed a study to implement and evaluate the effectiveness of an Atrial Fibrillation Decision Support Tool (AFDST) embedded within our electronic health record. METHODS: Our intervention is provider-facing and focused on decision support. The clinical setting is ambulatory patients being seen by primary care physicians. Patients include those with both incident and prevalent AF. This randomized, prospective trial will enroll 800 patients in our University of Cincinnati Health System who are currently receiving less than optimal anticoagulation therapy as determined by the AFDST. Patients will be randomized to one of two arms - 1) usual care, in which the AFDST is available for use; 2) addition of a best practice advisory (BPA) to the AFDST notifying the clinician that their patient stands to gain a significant benefit from a change in their current thromboprophylactic therapy. RESULTS: The primary outcome is effectiveness of the BPA measured by change to "appropriate thromboprophylaxis" based on the AFDST recommendation at 3 months post randomization. Secondary endpoints include Reach and Adoption, from the RE-AIM framework for implementation studies. Sample size is based upon an improvement from inappropriate to appropriate anticoagulation therapy estimated at 4% in the usual care arm and ≥10% in the experimental arm. CONCLUSION: Our goal is to examine whether addition of a BPA to an AFDST focused on primary care physicians in an ambulatory care setting will improve "appropriate thromboprophylaxis" compared with usual care. Results will be examined at 3 months post randomization and at the end of the study to evaluate durability of changes. We expect to complete patient enrollment by the end of June 2022. TRIAL REGISTRATION: Clinicaltrials.gov NCT04099485.

Unraveling racial disparities in asthma emergency department visits using electronic healthcare records and machine learning.

OBJECTIVE: Hospital emergency department (ED) visits by asthmatics differ based on race and season. The objectives of this study were to investigate season- and race-specific disparities for asthma risk, and to identify environmental exposure variables associated with ED visits among more than 42,000 individuals of African American (AA) and European American (EA) descent identified through electronic health records (EHRs). METHODS: We examined data from 42,375 individuals (AAs = 14,491, EAs = 27,884) identified in EHRs. We considered associated demographic (race, age, gender, insurance), clinical (smoking status, ED visits, FEV1%), and environmental exposures data (mold, pollen, and pollutants). Machine learning techniques, including random forest (RF), extreme gradient boosting (XGB), and decision tree (DT) were used to build and identify race- and -season-specific predictive models for asthma ED visits. RESULTS: Significant differences in ED visits and FEV1% among AAs and EAs were identified. ED visits by AAs was 32.0% higher than EAs and AAs had 6.4% lower FEV1% value than EAs. XGB model was used to accurately classify asthma patients visiting ED into AAs and EAs. Pollen factor and pollution (PM2.5, PM10) were the key variables for asthma in AAs and EAs, respectively. Age and cigarette smoking increase asthma risk independent of seasons. CONCLUSIONS: In this study, we observed racial and season-specific disparities between AAs and EAs asthmatics for ED visit and FEV1% severity, suggesting the need to address asthma disparities through key predictors including socio-economic status, particulate matter, and mold.

Racial and sex differences in optimizing anticoagulation therapy for patients with atrial fibrillation.

Study objective: Atrial fibrillation (AF) is the most common cardiac rhythm disorder, responsible for 15 % of strokes in the United States. Studies continue to document underuse of anticoagulation therapy in minority populations and women. Our objective was to compare the proportion of AF patients by race and sex who were receiving non-optimal anticoagulation as determined by an Atrial Fibrillation Decision Support Tool (AFDST). Design setting and participants: Retrospective cohort study including 14,942 patients within University of Cincinnati Health Care system. Data were analyzed between November 18, 2020, and November 20, 2021. Main outcomes and measures: Discordance between current therapy and that recommended by the AFDST. Results: In our two-category analysis 6107 (41 %) received non-optimal anticoagulation therapy, defined as current treatment category ≠ AFDST-recommended treatment category. Non-optimal therapy was highest in Black (42 % [n = 712]) and women (42 % [n = 2668]) and lower in White (39 % [n = 4748]) and male (40 % [n = 3439]) patients. Compared with White patients, unadjusted and adjusted odds ratios of receiving non-optimal anticoagulant therapy for Black patients were 1.13; 95 % CI, 1.02-1.30, p = 0.02; and 1.17; 95%CI, 1.04-1.31, p = 0.01; respectively, and 1.10; 95 % CI 1.03-1.18, p = 0.005; and 1.36; 95 % CI, 1.25-1.47, p < 0.001; for females compared with males. Conclusions and relevance: In patients with atrial fibrillation in the University of Cincinnati Health system, Black race and female sex were independently associated with an increased odds of receiving non-optimal anticoagulant therapy.

Incorporating Patients' Values and Preferences Into Decision Making About Transplantation of HCV-Naïve Recipients With Kidneys From HCV-Viremic Donors: A Feasibility Study.

Introduction. While use of (hepatitis C virus) HCV-viremic kidneys may result in net benefit for the average end-stage kidney disease (ESKD) patient awaiting transplantation, patients may have different values for ESKD-related health states. Thus, the best decision for any individual may be different depending on the balance of these factors. Our objective was to explore the feasibility of sampling health utilities from hemodialysis patients in order to perform patient-specific decision analyses considering various transplantation strategies. Study Design. We assessed utilities on a convenience sample of hemodialysis patients for health states including hemodialysis, and transplantation with either an HCV-uninfected kidney or an HCV-viremic kidney. We performed patient-specific decision analyses using each patient's age, race, gender, dialysis vintage, and utilities. We used a Markov state transition model considering strategies of continuing hemodialysis, transplantation with an HCV-unexposed kidney, and transplantation with an HCV-viremic kidney and HCV treatment. We interviewed 63 ESKD patients from four dialysis centers (Dialysis Clinic Inc., DCI) in the Cincinnati metropolitan area. Results. Utilities for ESKD-related health states varied widely from patient to patient. Mean values were highest for -transplantation with an HCV-uninfected kidney (0.89, SD: 0.18), and were 0.825 (SD: 0.231) and 0.755 (SD: 0.282), respectively, for hemodialysis and transplantation with an HCV-viremic kidney. Patient-specific decision analyses indicated 37 (59%) of the 63 ESKD patients in the cohort would have a net gain in quality-adjusted life years from transplantation of an HCV-viremic kidney, while 26 would have a net loss. Conclusions. It is feasible to gather dialysis patients' health state utilities and perform personalized decision analyses. This approach could be used in the future to guide shared decision-making discussions about transplantation strategies for ESKD patients.

New cytotoxic compounds from the leaves of Caesalpinia benthamiana (Baill.) Herend. & Zarucchi (Fabaceae).

OBJECTIVE: The incidence of multi-drug resistant cancer and the adverse effects associated with available chemotherapy have necessitated the search for new drug candidates. This study investigates the cytotoxic activity of Caesalpinia benthamiana. MATERIALS AND METHODS: Column chromatography (CC) and preparative thin layer chromatography (PTLC) were used to isolate compounds. Structural elucidation was done by spectroscopic analysis. MTT assay was used to evaluate cytotoxicity of the compounds against three human adenocarcinoma cells, using methotrexate and dimethyl sulfoxide (DMSO) as positive and negative controls, respectively. CyQuant direct cell proliferation and caspase-3/7 green detection assays were used to investigate the dichloromethane fraction. IC50 values of isolated compounds were determined from sigmoidal dose-response curve. RESULTS: Four new cytotoxic compounds, benthamianoate (2), benthamiacone (3), benthamianin (5) and benthamianol (6), and two known compounds, methyl gallate (1) and 2-methoxyacrylic acid (4) were identified. All the compounds were active with the new monoterpenoid characterized as benthamiacone exhibiting the highest activity (IC50 13.23-21.97 µg/ml) across cancer cell lines investigated. CyQuant direct cell proliferation assay showed significant reduction in the number of live carcinoma cells, while caspase-3/7 green detection assay showed significant increase in the number of dead carcinoma cells. CONCLUSION: This study revealed potential cytotoxic compounds which are here reported for the first time from C. benthamiana.

Chemistry and Pharmacology of Alkylamides from Natural Origin.

Interest in alkylamide, as a class of compound, has grown tremendously in recent years. This interest is due to the many presumed benefits in food, cosmetics, and medicine. This review focuses on the different alkylamides naturally occurring in many plant species. Several methods have been employed for their identification as well as isolation and several in vitro and in vivo studies have revealed their therapeutic effects in various diseases. In general, alkylamides have been reported to have several biological activities and pharmacological effects which include immunomodulatory, antithrombotic, antimicrobial, antiviral, antioxidant, anti-inflammatory, analgesic, anticancer, antidiabetic, and antiprotozoal activities. Moreover, many studies have reported on their mechanisms of action, structure-activity relationship, pharmacokinetics, and toxicity. We herein present an updated report on the chemistry and pharmacology of alkylamides of natural origin.

Automated Tool for Health Utility Assessments: The Gambler II.

Background. The Gambler II is a web-based utility assessment tool supporting visual analogue scale (VAS), standard gamble (SG), and time trade-off (TTO) utility assessments. It contains novel features, including an easy to use project development authoring tool and use of multimedia clips for health state descriptions. Objectives. Evaluate the usability and understandability of the patient-facing side of The Gambler. Investigate the feasibility of using The Gambler and evaluate its impact on patient knowledge regarding the relevant health states. Materials and Methods. We used The Gambler to assess utilities on a convenience sample of 55 users for common long-term complications of type 2 diabetes mellitus: diabetic neuropathy, diabetic retinopathy, and diabetic foot infection requiring transmetatarsal amputation. Using VAS, SG, and TTO, we collected metadata, such as time spent on each assessment and the entire assessment process. We evaluated usability with an adaptation of the System Usability Scale survey and understandability. We evaluated impact on knowledge gained through knowledge assessments about these complications before and after use of The Gambler. Results. Overall satisfaction with The Gambler was high, 4.02 on a 5-point scale. Usability rated highly at 84.93 on a normalized scale between 0 and 100. Knowledge scores increased significantly following use of The Gambler from pretest mean of 68% to posttest mean of 76% (P < 0.01). Average time using the software: ∼7½ minutes. Conclusions. The Gambler is an easy to use and understand computer-based tool for utility assessment. It is feasible to use within clinical encounters to support shared decision making, and it has unique features that make it a powerful tool for investigators interested in research on health utilities.

Bicycloheptylamine-Doxorubicin Conjugate: Synthesis and Anticancer Activities in σ2 Receptor-Expressing Cell Lines.

BACKGROUND: Novel bicycloheptylamines were designed and synthesized. These compounds were found to be selective for sigma-2 receptors. These receptors have been found to be up to 10 fold over-expressed in certain cancer cell lines, leading to investigation of possible uses as a biomarker in diagnosis and/or treatment especially in cancers with poor prognosis. OBJECTIVES: The aim was to conjugate a novel sigma-2 receptor ligand to doxorubicin to examine anticancer activities, with and without conjugation, and therefore possibilities in drug delivery. METHODS: Conjugation was conducted using N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide HCl as a coupling agent. Affinity towards the sigma-2 receptor was tested using ligand-receptor binding studies. Anticancer activities against cancer cell lines were carried out using cell viability assays. Caspase dependency was tested using Z-VAD-FMK, a pan-caspase inhibitor, to begin to investigate mechanisms of action. RESULTS: The target compound retained affinity towards the sigma-2 receptor and exhibited potent anticancer activities on cancer cell lines expressing the sigma-2 receptor. The potencies exceeded those of doxorubicin, the lead sigma-2 receptor ligand, as well as non-covalent combination of both drugs. The activity was also found to be caspase-dependent. CONCLUSION: The conjugation of target bicycloheptylamines with cytotoxic moieties may yield potent and selective molecules for detection and/or treatment of certain cancers.

Pharmacological characterizations of the 'legal high' fluorolintane and isomers.

1,2-Diarylethylamines represent a class of molecules that have shown potential in the treatment of pain, epilepsy, neurodegenerative disease and depression. Examples include lefetamine, remacemide, and lanicemine. Recently, several 1,2-diarylethylamines including the dissociatives diphenidine, methoxphenidine and ephenidine as well as the opioid MT-45, have appeared as 'research chemicals' or 'legal highs'. Due to their recent emergence little is known about their pharmacology. One of these, 1-[1-(2-fluorophenyl)-2-phenylethyl]pyrrolidine (fluorolintane, 2-F-DPPy), is available for purchase with purported dissociative effects intended to resemble phencyclidine (PCP) and ketamine. To better understand this emerging class, pharmacological investigations were undertaken for the first time on fluorolintane and its five aryl-fluorine-substituted isomers. In vitro binding studies revealed high affinity for N-methyl-D-aspartate (NMDA) receptors with fluorolintane (Ki = 87.92 nM) with lesser affinities for related compounds. Additional affinities were seen for all compounds at several sites including norepinephrine (NET), serotonin (SERT) and dopamine (DAT) transporters, and sigma receptors. Notably high affinities at DAT were observed, which were in most cases greater than NMDA receptor affinities. Additional functional and behavioral experiments show fluorolintane inhibited NMDA receptor-induced field excitatory postsynaptic potentials in rat hippocampal slices and inhibited long-term potentiation induced by theta-burst stimulation in rat hippocampal slices with potencies consistent with its NMDA receptor antagonism. Finally fluorolintane inhibited prepulse inhibition in rats, a measure of sensorimotor gating, with a median effective dose (ED50) of 13.3 mg/kg. These findings are consistent with anecdotal reports of dissociative effects of fluorolintane in humans.

Syntheses and analytical characterizations of the research chemical 1-[1-(2-fluorophenyl)-2-phenylethyl]pyrrolidine (fluorolintane) and five of its isomers.

A number of substances based on the 1,2-diarylethylamine template have been investigated for various potential clinical applications whereas others have been encountered as research chemicals sold for non-medical use. Some of these substances have transpired to function as NMDA receptor antagonists that elicit dissociative effects in people who use these substances recreationally. 1-[1-(2-Fluorophenyl)-2-phenylethyl]pyrrolidine (fluorolintane, 2-F-DPPy) has recently appeared as a research chemical, which users report has dissociative effects. One common difficulty encountered by stakeholders confronting the appearance of new psychoactive substances is the presence of positional isomers. In the case of fluorolintane, the presence of the fluorine substituent on either the phenyl and benzyl moieties of the 1,2-diarylethylamine structure results in a total number of six possible racemic isomers, namely 2-F-, 3-F-, and 4-F-DPPy (phenyl ring substituents) and 2"-F-, 3"-F-, and 4"-F-DPPy (benzyl ring substituents). The present study reports the chemical syntheses and comprehensive analytical characterizations of the two sets of three positional isomers. These studies included various low- and high-resolution mass spectrometry platforms, gas- and liquid chromatography (GC and LC), nuclear magnetic resonance (NMR) spectroscopy and GC-condensed phase and attenuated total reflection infrared spectroscopy analyses. The differentiation between each set of three isomers was possible under a variety of experimental conditions including GC chemical ionization triple quadrupole tandem mass spectrometric analysis of the [M + H - HF]+ species. The latter MS method was particularly helpful as it revealed distinct formations of product ions for each of the six investigated substances.

Syntheses, analytical and pharmacological characterizations of the 'legal high' 4-[1-(3-methoxyphenyl)cyclohexyl]morpholine (3-MeO-PCMo) and analogues.

New psychoactive substances (NPS) are commonly referred to as 'research chemicals', 'designer drugs' or 'legal highs'. One NPS class is represented by dissociative anesthetics, which include analogues of the arylcyclohexylamine phencyclidine (PCP), ketamine and diphenidine. A recent addition to the NPS market was 4-[1-(3-methoxyphenyl)cyclohexyl]morpholine (3-MeO-PCMo), a morpholine analogue of 3-MeO-PCP. Although suspected to have dissociative effects in users, information about its pharmacological profile is not available. From clinical and forensic perspectives, detailed analytical data are needed for identification, especially when facing the presence of positional isomers, as these are frequently unavailable commercially. This study presents the analytical and pharmacological characterization of 3-MeO-PCMo along with five additional analogues, namely the 2- and 4-MeO-PCMo isomers, 3,4-methylenedioxy-PCMo (3,4-MD-PCMo), 3-Me-PCMo and PCMo. All six arylcyclohexylmorpholines were synthesized and characterized using chromatographic, mass spectrometric and spectroscopic techniques. The three positional isomers could be differentiated and the identity of 3-MeO-PCMo obtained from an internet vendor was verified. All six compounds were also evaluated for affinity at 46 central nervous system receptors including the N-methyl-d-aspartate receptor (NMDAR), an important target for dissociative anesthetics such as PCP and ketamine. In vitro binding studies using (+)-[3-3 H]-MK-801 in rat forebrain preparations revealed moderate affinity for NMDAR in the rank order of 3-Me >3-MeO > PCMo >3,4-MD > 2-MeO > 4-MeO-PCMo. 3-MeO-PCMo was found to have moderate affinity for NMDAR comparable to that of ketamine, and had an approximate 12-fold lower affinity than PCP. These results support the anecdotal reports of dissociative effects from 3-MeO-PCMo in humans.

Developing selective histone deacetylases (HDACs) inhibitors through ebselen and analogs.

Histone deacetylases (HDACs) are key regulators of gene expression in cells and have been investigated as important therapeutic targets for cancer and other diseases. Different subtypes of HDACs appear to play disparate roles in the cells and are associated with specific diseases. Therefore, substantial effort has been made to develop subtype-selective HDAC inhibitors. In an effort to discover existing scaffolds with HDAC inhibitory activity, we screened a drug library approved by the US Food and Drug Administration and a National Institutes of Health Clinical Collection compound library in HDAC enzymatic assays. Ebselen, a clinical safe compound, was identified as a weak inhibitor of several HDACs, including HDAC1, HDAC3, HDAC4, HDAC5, HDAC6, HDAC7, HDAC8, and HDAC9 with half maximal inhibitory concentrations approximately single digit of µM. Two ebselen analogs, ebselen oxide and ebsulfur (a diselenide analog of ebselen), also inhibited these HDACs, however with improved potencies on HDAC8. Benzisothiazol, the core structure of ebsulfur, specifically inhibited HDAC6 at a single digit of µM but had no inhibition on other HDACs. Further efforts on structure-activity relationship based on the core structure of ebsulfur led to the discovery of a novel class of potent and selective HDAC6 inhibitors with RBC-2008 as the lead compound with single-digit nM potency. This class of histone deacetylase inhibitor features a novel pharmacophore with an ebsulfur scaffold selectively targeting HDAC6. Consistent with its inhibition on HDAC6, RBC-2008 significantly increased the acetylation levels of α-tubulin in PC-3 cells. Furthermore, treatment with these compounds led to cell death of multiple tumor cell lines in a dose-dependent manner. These results demonstrated that ebselen and ebsulfur analogs are inhibitors of HDACs, supporting further preclinical development of this class of compounds for potential therapeutic applications.

Pharmacological Investigations of the Dissociative 'Legal Highs' Diphenidine, Methoxphenidine and Analogues.

1,2-Diarylethylamines including lanicemine, lefetamine, and remacemide have clinical relevance in a range of therapeutic areas including pain management, epilepsy, neurodegenerative disease and depression. More recently 1,2-diarylethylamines have been sold as 'legal highs' in a number of different forms including powders and tablets. These compounds are sold to circumvent governmental legislation regulating psychoactive drugs. Examples include the opioid MT-45 and the dissociative agents diphenidine (DPH) and 2-methoxy-diphenidine (2-MXP). A number of fatal and non-fatal overdoses have been linked to abuse of these compounds. As with many 'legal highs', little is known about their pharmacology. To obtain a better understanding, the effects of DPH, 2-MXP and its 3- and 4-MeO- isomers, and 2-Cl-diphenidine (2-Cl-DPH) were investigated using binding studies at 46 central nervous system receptors including the N-methyl-D-aspartate receptor (NMDAR), serotonin, dopamine, norepinephrine, histamine, and sigma receptors as well as the reuptake transporters for serotonin, dopamine and norepinephrine. Reuptake inhibition potencies were measured at serotonin, norepinephrine and dopamine transporters. NMDAR antagonism was established in vitro using NMDAR-induced field excitatory postsynaptic potential (fEPSP) experiments. Finally, DPH and 2-MXP were investigated using tests of pre-pulse inhibition of startle (PPI) in rats to determine whether they reduce sensorimotor gating, an effect observed with known dissociative drugs such as phencyclidine (PCP) and ketamine. The results suggest that these 1,2-diarylethylamines are relatively selective NMDAR antagonists with weak off-target inhibitory effects on dopamine and norepinephrine reuptake. DPH and 2-MXP significantly inhibited PPI. DPH showed greater potency than 2-MXP, acting with a median effective dose (ED50) of 9.5 mg/kg, which is less potent than values reported for other commonly abused dissociative drugs such as PCP and ketamine.

Syntheses and analytical characterizations of N-alkyl-arylcyclohexylamines.

The rise in new psychoactive substances that are available as 'research chemicals' (RCs) remains a significant forensic and legislative challenge. A number of arylcyclohexylamines have attracted attention as RCs and continue to be encountered, including 3-MeO-PCP, 3-MeO-PCE and 3-MeO-PCPr. These compounds are commonly perceived as ketamine-like dissociative substances and are believed to act predominantly via antagonism of the N-methyl-D-aspartate (NMDA) receptor. To aid in the identification of newly emerging substances of abuse, the current studies were performed. The syntheses of fifteen N-alkyl-arylcyclohexylamines are described. Analytical characterizations were performed via gas chromatography and high performance liquid chromatography coupled to multiple forms of mass spectrometry as well as nuclear magnetic resonance spectroscopy, ultraviolet diode array detection and infrared spectroscopy. The series consisted of the N-alkyl derivatives (N-methyl, N-ethyl, N-propyl) of phenyl-substituted and isomeric 2-, 3- and 4-methoxy phenylcyclohexylamines, as well as the N-alkyl derivatives obtained from 3-methylphenyl and 2-thienyl moieties. In addition to the presentation of a range of previously unreported data, it was also found that positional isomers of aryl methoxyl-substituted arylcyclohexylamines were readily distinguishable under a variety of analytical conditions. Copyright © 2015 John Wiley & Sons, Ltd.