High-potency Compounds Research Articles

Ridge regression coupled with a new uninformative variable elimination algorithm as a new descriptor screening method: Application of data reduction in QSAR study of some sulfonated derivatives as c-Met inhibitors

An uninformative variable elimination algorithm was combined with the Ridge regression method. This combination makes the penalized Ridge method, which is essentially incapable of deleting or selecting a variable, an efficient descriptor screening method for screening of descriptors in QSAR studies. The importance of descriptors was used to identify uninformative and redundant descriptors. The descriptor importance was defined as the ratio of the mean coefficients to the standard deviation of the coefficients derived from the leave-one-out (LOO) Ridge models. Then, with an iterative algorithm, among 392 molecular descriptors obtained after initial preprocessing, 358 uninformative descriptors were identified and removed from the data set. The remaining 34 descriptors were used for further variable selection and modeling through the smoothly clipped absolute deviation (SCAD) method. The proposed screening method was used to screen and reduce the size of QSAR data containing 63 compounds as c-Met inhibitors with anti-cancer activity. For comparison, the SCAD models were constructed using original high-dimensional data (SCAD), and the reduced-size data via the UVE-Ridge screening method (UVE-Ridge-SCAD). Both models were used to predict biological activities (pIC50) for compounds in the external test set. The coefficients of determination (R2) and the FIT parameter for the test data predicted using the SCAD model (with 12 selected descriptors) were equal to 0.8042 and 3.78, respectively. The UVE-Ridge-SCAD model (with 9 descriptors) showed R2 and FIT values of 0.9025 and 4.38, respectively. Higher R2 and FIT values indicate the excellent predictive power of the UVE-Ridge-SCAD model. Finally, the UVE-Ridge-SCAD model was used to suggest new high-potency compounds. The accuracy of the proposed compounds was investigated using ligand-receptor interactions.

Protein engineering approach to enhance activity assays of mono-ADP-ribosyltransferases through proximity.

Human mono-ADP-ribosylating PARP enzymes have been linked to several clinically relevant processes and many of these PARPs have been suggested as potential drug targets. Despite recent advances in the field, efforts to discover inhibitors have been hindered by the lack of tools to rapidly screen for high potency compounds and profile them against the different enzymes. We engineered mono-ART catalytic fragments to be incorporated into a cellulosome-based octavalent scaffold. Compared to the free enzymes, the scaffold-based system results in an improved activity for the tested PARPs due to improved solubility, stability and the proximity of the catalytic domains, altogether boosting their activity beyond 10-fold in the case of PARP12. This allows us to measure their activity using a homogeneous NAD+ conversion assay, facilitating its automation to lower the assay volume and costs. The approach will enable the discovery of more potent compounds due to increased assay sensitivity.

Fenofibrate inhibits hypoxia-inducible factor-1 alpha and carbonic anhydrase expression through activation of AMP-activated protein kinase/HO-1/Sirt1 pathway in glioblastoma cells.

Cancer and its associated conditions have significant impacts on public health at many levels worldwide, and cancer is the leading cause of death among adults. Peroxisome proliferator-activated receptor α (PPARα)-specific agonists, fibrates, have been approved by the Food and Drug Administration for managing hyperlipidemia. PPARα-specific agonists exert anti-cancer effects in many human cancer types, including glioblastoma (GBM). Recently, we have reported that the hypoxic state in GBM stabilizes hypoxia-inducible factor-1 alpha (HIF-1α), thus contributing to tumor escape from immune surveillance by activating the expression of the pH-regulating protein carbonic anhydrase IX (CA9). In this study, we aimed to study the regulatory effects of the PPARα agonist fibrate on the regulation of HIF-1α expression and its downstream target protein in GBM. Our findings showed that fenofibrate is the high potency compound among the various fibrates that inhibit hypoxia-induced HIF-1α and CA9 expression in GBM. Moreover, fenofibrate-inhibited HIF-1α expression is mediated by HO-1 activation in GBM cells through the AMP-activated protein kinase (AMPK) pathway. In addition, fenofibrate-enhanced HO-1 upregulation activates SIRT1 and leads to subsequent accumulation of SIRT1 in the nucleus, which further promotes HIF-1α deacetylation and inhibits CA9 expression. Using a protein synthesis inhibitor, cycloheximide, we also observed that fenofibrate inhibited HIF-1α protein synthesis. In addition, the administration of the proteasome inhibitor MG132 showed that fenofibrate promoted HIF-1α protein degradation in GBM. Hence, our results indicate that fenofibrate is a useful anti-GBM agent that modulates hypoxia-induced HIF-1α expression through multiple cellular pathways.

The evaluation of 1-tetralone and 4-chromanone derivatives as inhibitors of monoamine oxidase

Monoamine oxidase (MAO) is of much clinical relevance, and inhibitors of this enzyme are used in the treatment for neuropsychiatric and neurodegenerative disorders such as depression and Parkinson’s disease. The present study synthesises and evaluates the MAO inhibition properties of a series of 33 1-tetralone and 4-chromanone derivatives in an attempt to discover high-potency compounds and to expand on the structure–activity relationships of MAO inhibition by these classes. Among these series, eight submicromolar MAO-A inhibitors and 28 submicromolar MAO-B inhibitors are reported, with all compounds acting as specific inhibitors of the MAO-B isoform. The most potent inhibitor was a 1-tetralone derivative (1h) with IC50 values of 0.036 and 0.0011 µM for MAO-A and MAO-B, respectively. Interestingly, with the reduction of 1-tetralones to the corresponding alcohols, a decrease in MAO inhibition potency is observed. Among these 1-tetralol derivatives, 1p (IC50 = 0.785 μM) and 1o (IC50 = 0.0075 μM) were identified as particularly potent inhibitors of MAO-A and MAO-B, respectively. Potent compounds such as those reported here may act as leads for the future development of MAO-B specific inhibitors.Graphic abstractThe present study describes the MAO inhibitory activities of a series of 1-tetralone and 4-chromanone derivatives. Numerous high-potency MAO-B specific inhibitors were identified.Electronic supplementary materialThe online version of this article (10.1007/s11030-020-10143-w) contains supplementary material, which is available to authorised users.

Synthesis and biological evaluation of Vinpocetine derivatives

A new series of Vinpocetine derivatives were synthesized and evaluated for their inhibitory activity on PDE1A in vitro. Seven compounds with higher inhibitory activity were selected for surface plasmon resonance (SPR) binding experiments. Compared with Vinpocetine, these high potency compounds presented a higher binding affinity with PDE1A, which was consistent with inhibitory activity. After further screening, compounds 5, 7, 21, 34 and Vinpocetine were selected to examine the vasorelaxant effects on endothelium-intact rat thoracic aortic rings. The study suggested that the effects of compounds 7 and 21 were the most significant with the maximum value of 93.46 ± 0.77% and 92.90 ± 0.78% (n = 5) at a concentration of 100 μM respectively. Based on these studies, compounds 7 and 21 were considered for further development as hit compounds.

An Autoinducer Analogue Reveals an Alternative Mode of Ligand Binding for the LasR Quorum-Sensing Receptor

Bacteria use a cell-cell communication process called quorum sensing to coordinate collective behaviors. Quorum sensing relies on production and group-wide detection of extracellular signal molecules called autoinducers. Here, we probe the activity of the Pseudomonas aeruginosa LasR quorum-sensing receptor using synthetic agonists based on the structure of the native homoserine lactone autoinducer. The synthetic compounds range from low to high potency, and agonist activity tracks with the ability of the agonist to stabilize the LasR protein. Structural analyses of the LasR ligand binding domain complexed with representative synthetic agonists reveal two modes of ligand binding, one mimicking the canonical autoinducer binding arrangement, and the other with the lactone head group rotated approximately 150°. Iterative mutagenesis combined with chemical synthesis reveals the amino acid residues and the chemical moieties, respectively, that are key to enabling each mode of binding. Simultaneous alteration of LasR residues Thr75, Tyr93, and Ala127 converts low-potency compounds into high-potency compounds and converts ligands that are nearly inactive into low-potency compounds. These results show that the LasR binding pocket displays significant flexibility in accommodating different ligands. The ability of LasR to bind ligands in different conformations, and in so doing, alter their potency as agonists, could explain the difficulties that have been encountered in the development of competitive LasR inhibitors.

Regulation of Pain and Itch by TRP Channels.

Nociception is an important physiological process that detects harmful signals and results in pain perception. In this review, we discuss important experimental evidence involving some TRP ion channels as molecular sensors of chemical, thermal, and mechanical noxious stimuli to evoke the pain and itch sensations. Among them are the TRPA1 channel, members of the vanilloid subfamily (TRPV1, TRPV3, and TRPV4), and finally members of the melastatin group (TRPM2, TRPM3, and TRPM8). Given that pain and itch are pro-survival, evolutionarily-honed protective mechanisms, care has to be exercised when developing inhibitory/modulatory compounds targeting specific pain/itch-TRPs so that physiological protective mechanisms are not disabled to a degree that stimulus-mediated injury can occur. Such events have impeded the development of safe and effective TRPV1-modulating compounds and have diverted substantial resources. A beneficial outcome can be readily accomplished via simple dosing strategies, and also by incorporating medicinal chemistry design features during compound design and synthesis. Beyond clinical use, where compounds that target more than one channel might have a place and possibly have advantageous features, highly specific and high-potency compounds will be helpful in mechanistic discovery at the structure-function level.

YAP Suppresses Lung Squamous Cell Carcinoma Progression via Deregulation of the DNp63-GPX2 Axis and ROS Accumulation.

Lung squamous cell carcinoma (SCC), accounting for approximately 30% of non-small cell lung cancer, is often refractory to therapy. Screening a small-molecule library, we identified digitoxin as a high potency compound for suppressing human lung SCC growth in vitro and in vivo Mechanistic investigations revealed that digitoxin attenuated YAP phosphorylation and promoted YAP nuclear sequestration. YAP activation led to excessive accumulation of reactive oxygen species (ROS) by downregulating the antioxidant enzyme GPX2 in a manner related to p63 blockade. In patient-derived xenograft models, digitoxin treatment efficiently inhibited lung SCC progression in correlation with reduced expression of YAP. Collectively, our results highlight a novel tumor-suppressor function of YAP via downregulation of GPX2 and ROS accumulation, with potential implications to improve precision medicine of human lung SCC. Cancer Res; 77(21); 5769-81. ©2017 AACR.

Flupenthixol versus low-potency first-generation antipsychotic drugs for schizophrenia.

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between antipsychotic drugs, however, low-potency antipsychotic drugs are sometimes perceived as less efficacious than high-potency compounds by clinicians, and they also seem to differ in their side effects. To review the effects in clinical response of flupenthixol and low-potency antipsychotics for people with schizophrenia. We searched the Cochrane Schizophrenia Group Trials Register (July 2010). Randomised controlled trials that compared flupenthixol with first-generation low-potency antipsychotic drugs for people with schizophrenia or schizophrenia-like psychosis. We extracted data independently. For continuous data, we calculated mean differences (MD) based on a random-effects model. The review currently includes one randomised trial from mainland China with 153 participants that lasted two months and compared flupenthixol with chlorpromazine. The exact methods of sequence generation and allocation concealment were not reported, and medication was provided in an open manner. There were no data on the outcomes that we had a priori selected for a 'Summary of findings' table.There was no significant difference between flupenthixol and chlorpromazine in the participants' general mental state at endpoint as measured by the Brief Psychiatric Rating Scale (BPRS) total score (1 randomised controlled trial (RCT), n = 153, MD 2.20 95% confidence interval (CI) -1.25 to 5.65). Chlorpromazine was associated with significantly less dizziness (1 RCT, n = 153, MD 0.12 95% CI 0.01 to 0.23); dystonia (1 RCT, n = 153, MD 0.29 95% CI 0.13 to 0.45); unsteady gait (1 RCT, n = 153, MD 0.46 95% CI 0.28 to 0.64); reduced facial expression (1 RCT, n = 153, MD 0.27 95% CI 0.09 to 0.45); restlessness (1 RCT, n = 153, MD 0.69 95% CI 0.45 to 0.93); rigidity (elbow) (1 RCT, n = 153, MD 0.48 95% CI 0.28 to 0.68); and tremor (1 RCT, n = 153, MD 0.56 95% CI 0.34 to 0.78). Chlorpromazine produced more dryness of mouth than flupenthixol (1 RCT, n = 153, MD -0.14 95% CI -0.25 to -0.03). The evidence base of flupenthixol versus low-potency first-generation antipsychotics is currently restricted to one randomised comparison with chlorpromazine. The few reported data do not suggest a difference in efficacy, but flupenthixol appeared to produce more movement disorders and dizziness, while chlorpromazine was associated with the anticholinergic side effect - dryness of mouth. More trials are needed to make conclusions about the relative effects of flupenthixol and low-potency antipsychotics.

Haloperidol versus low-potency first-generation antipsychotic drugs for schizophrenia

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between antipsychotic compounds, however, low-potency antipsychotic drugs are often clinically perceived as less efficacious than high-potency compounds, and they also

Fluphenazine versus low-potency first-generation antipsychotic drugs for schizophrenia.

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between any other antipsychotic compounds, however, low-potency antipsychotic drugs are often perceived as less efficacious than high-potency compounds by clinicians, and they also seem to differ in their side effects. This review examined the effects of the high-potency antipsychotic fluphenazine compared to those of low-potency antipsychotics. To review the effects of fluphenazine and low-potency antipsychotics for people with schizophrenia. We searched the Cochrane Schizophrenia Group Trials Register (November 2010). We included all randomised controlled trials (RCTs) comparing fluphenazine with first-generation low-potency antipsychotic drugs for people with schizophrenia or schizophrenia-like psychosis. We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. The review currently includes seven randomised trials and 1567 participants that compared fluphenazine with low-potency antipsychotic drugs. The size of the included studies was between 40 and 438 participants. Overall, sequence generation, allocation procedures and blinding were poorly reported. Fluphenazine was not significantly different from low-potency antipsychotic drugs in terms of response to treatment (fluphenazine 55%, low-potency drug 55%, 2 RCTs, n = 105, RR 1.06 CI 0.75 to 1.50, moderate quality evidence). There was also no significant difference in acceptability of treatment with equivocal numbers of participants leaving the studies early due to any reason (fluphenazine 36%, low-potency antipsychotics 36%, 6 RCTs, n = 1532, RR 1.00 CI 0.88 to 1.14, moderate quality evidence). There was no significant difference between fluphenazine and low-potency antipsychotics for numbers experiencing at least one adverse effect (fluphenazine 70%, low-potency antipsychotics 88%, 1 RCT, n = 65, RR 0.79 CI 0.58 to 1.07, moderate quality evidence). However, at least one movement disorder occurred significantly more frequently in the fluphenazine group (fluphenazine 15%, low-potency antipsychotics 10%, 3 RCTs, n = 971, RR 2.11 CI 1.41 to 3.15, low quality of evidence). In contrast, low-potency antipsychotics produced significantly more sedation (fluphenazine 20%, low-potency antipsychotics 64%, 1 RCT, n = 65, RR 0.31 CI 0.13 to 0.77, high quality evidence). No data were available for the outcomes of death and quality of life. The results of the primary outcome were robust in a number of subgroup and sensitivity analyses.Adverse effects such as akathisia (fluphenazine 15%, low-potency antipsychotics 6%, 5 RCTs, n = 1209, RR 2.28 CI 1.58 to 3.28); dystonia (fluphenazine 5%, low-potency antipsychotics 2%, 4 RCTs, n = 1309, RR 2.66 CI 1.25 to 5.64); loss of associated movement (fluphenazine 20%, low-potency antipsychotics 2%, 1 RCT, n = 338, RR 11.15 CI 3.95 to 31.47); rigor (fluphenazine 27%, low-potency antipsychotics 12%, 2 RCTs, n = 403, RR 2.18 CI 1.20 to 3.97); and tremor (fluphenazine 15%, low-potency antipsychotics 6%, 2 RCTs, n = 403, RR 2.53 CI 1.37 to 4.68) occurred significantly more frequently in the fluphenazine group.For other adverse effects such as dizziness (fluphenazine 8%, low-potency antipsychotics 17%, 4 RCTs, n = 1051, RR 0.49 CI 0.32 to 0.73); drowsiness (fluphenazine 18%, low-potency antipsychotics 25%, 3 RCTs, n = 986, RR 0.67 CI 0.53 to 0.86); dry mouth (fluphenazine 11%, low-potency antipsychotics 18%, 4 RCTs, n = 1051, RR 0.63 CI 0.45 to 0.89); nausea (fluphenazine 4%, low-potency antipsychotics 15%, 3 RCTs, n = 986, RR 0.25 CI 0.14 to 0.45); and vomiting (fluphenazine 3%, low-potency antipsychotics 8%, 3 RCTs, n = 986, RR 0.36 CI 0.18 to 0.72) results favoured fluphenazine with significantly more events occurring in the low-potency antipsychotic group for these outcomes. The results do not show a clear difference in efficacy between fluphenazine and low-potency antipsychotics. The number of included studies was low and their quality moderate. Therefore, further studies would be needed to draw firm conclusions about the relative effects of fluphenazine and low-potency antipsychotics.

Haloperidol versus low-potency first-generation antipsychotic drugs for schizophrenia.

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between antipsychotic compounds, however, low-potency antipsychotic drugs are often clinically perceived as less efficacious than high-potency compounds, and they also seem to differ in their side-effects. To review the effects in clinical response of haloperidol and low-potency antipsychotics for people with schizophrenia. We searched the Cochrane Schizophrenia Group Trials Register (July 2010). We included all randomised trials comparing haloperidol with first-generation low-potency antipsychotic drugs for people with schizophrenia or schizophrenia-like psychosis. We extracted data independently. For dichotomous data, we calculated risk ratios (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. For continuous data, we calculated mean differences (MD), again based on a random-effects model. The review currently includes 17 randomised trials and 877 participants. The size of the included studies was between 16 and 109 participants. All studies were short-term with a study length between two and 12 weeks. Overall, sequence generation, allocation procedures and blinding were poorly reported. We found no clear evidence that haloperidol was superior to low-potency antipsychotic drugs in terms of clinical response (haloperidol 40%, low-potency drug 36%, 14 RCTs, n = 574, RR 1.11, CI 0.86 to 1.44 lowquality evidence). There was also no clear evidence of benefit for either group in acceptability of treatment with equivocal difference in the number of participants leaving the studies early due to any reason (haloperidol 13%, low-potency antipsychotics 17%, 11 RCTs, n = 408, RR 0.82, CI 0.38 to 1.77, low quality evidence). Similar equivocal results were found between groups for experiencing at least one adverse effect (haloperidol 70%, low-potency antipsychotics 35%, 5 RCTs n = 158, RR 1.97, CI 0.69 to 5.66, very low quality evidence ). More participants from the low-potency drug group experienced sedation (haloperidol 14%, low-potency antipsychotics 41%, 2 RCTs, n = 44, RR 0.30, CI 0.11 to 0.82, moderate quality evidence), orthostasis problems (haloperidol 25%, low-potency antipsychotics 71%, 1 RCT, n = 41, RR 0.35, CI 0.16 to 0.78) and weight gain (haloperidol 5%, low-potency antipsychotics 29%, 3 RCTs, n = 88, RR 0.22, CI 0.06 to 0.81). In contrast, the outcome 'at least one movement disorder' was more frequent in the haloperidol group (haloperidol 72%, low-potency antipsychotics 41%, 5 RCTs, n = 170, RR 1.64, CI 1.22 to 2.21, low quality evidence). No data were available for death or quality of life. The results of the primary outcome were robust in several subgroup and sensitivity analyses. The results do not clearly show a superiority in efficacy of haloperidol compared with low-potency antipsychotics. Differences in adverse events were found for movement disorders, which were more frequent in the haloperidol group, and orthostatic problems, sedation and weight gain, which were more frequent in the low-potency antipsychotic group. The quality of studies was low, and the quality of evidence for the main outcomes of interest varied from moderate to very low, so more newer studies would be needed in order to draw a definite conclusion about whether or not haloperidol is superior or inferior to low-potency antipsychotics.

Trifluoperazine versus low-potency first-generation antipsychotic drugs for schizophrenia.

Antipsychotic drugs are the core treatment for schizophrenia. Treatment guidelines state that there is no difference in efficacy between any other antipsychotic compounds, however, low-potency antipsychotic drugs are often perceived as less efficacious than high-potency compounds by clinicians, and they also seem to differ in their side-effects. To review the effects in response to treatment of trifluoperazine and low-potency antipsychotics for people with schizophrenia. We searched the Cochrane Schizophrenia Group's Trials Register (November 2010). We included all randomised trials comparing trifluoperazine with first-generation low-potency antipsychotic drugs for people with schizophrenia or schizophrenia-like psychosis. We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. The review currently includes seven randomised trials involving 422 participants that compared trifluoperazine with low-potency antipsychotic drugs. The size of the included studies was between 20 and 157 participants with a study length between four and 52 weeks. Overall, sequence generation, allocation procedures and blinding were poorly reported. Trifluoperazine was not significantly different from low-potency antipsychotic drugs in terms of response to treatment (trifluoperazine 26%, low-potency drug 27%, 3 RCTs, n = 120, RR 0.96 CI 0.59 to 1.56, moderate quality evidence). There was also no significant difference in acceptability of treatment with equivocal number of participants leaving the studies early due to any reason (trifluoperazine 20%, low-potency antipsychotics 16%, 3 RCTs, n = 239, RR 1.25, CI 0.72 to 2.17,low quality evidence). There was no significant difference in numbers with at least one adverse effect (trifluoperazine 60%, low-potency antipsychotics 38%, 1 RCT, n = 60, RR 1.60, CI 0.94 to 2.74, moderate quality evidence). However, at least one movement disorder was significantly more frequent in the trifluoperazine group (trifluoperazine 23%, low-potency antipsychotics 13%, 2 RCTs, n = 123, RR 2.08 CI 0.78 to 5.55, very low quality evidence) as well as incoordination (trifluoperazine 20%, low-potency antipsychotics 5%, 1 RCT, n = 60, RR 7.00, CI 1.60 to 30.66) and rigor (trifluoperazine 45%, low-potency antipsychotics 10%, 1 RCT, n = 60, RR 4.50, CI 1.58 to 12.84). No data were available for other outcomes of interest death, sedation and quality of life. The results did not show a difference in efficacy between trifluoperazine and low-potency antipsychotics. Trifluoperazine produced more movement disorders. The number of randomised studies as well as their quality is low, the quality of evidence for outcomes of interest ranged from moderate to very low quality, so more, newer studies would be needed for conclusions about the relative effects of trifluoperazine and low-potency antipsychotics.

AZ-4217: A High Potency BACE Inhibitor Displaying Acute Central Efficacy in Different In Vivo Models and Reduced Amyloid Deposition in Tg2576 Mice

Aβ, the product of APP (amyloid precursor protein), has been implicated in the pathophysiology of Alzheimer's disease (AD). β-Site APP cleaving enzyme1 (BACE1) is the enzyme initiating the processing of the APP to Aβ peptides. Small molecule BACE1 inhibitors are expected to decrease Aβ-peptide generation and thereby reduce amyloid plaque formation in the brain, a neuropathological hallmark of AD. BACE1 inhibition thus addresses a key mechanism in AD and its potential as a therapeutic target is currently being addressed in clinical studies. Here, we report the discovery and the pharmacokinetic and pharmacodynamic properties of BACE1 inhibitor AZ-4217, a high potency compound (IC50 160 pM in human SH-SY5Y cells) with an excellent in vivo efficacy. Central efficacy of BACE1 inhibition was observed after a single dose in C57BL/6 mice, guinea pigs, and in an APP transgenic mouse model of cerebral amyloidosis (Tg2576). Furthermore, we demonstrate that in a 1 month treatment paradigm BACE1 inhibition of Aβ production does lower amyloid deposition in 12-month-old Tg2576 mice. These results strongly support BACE1 inhibition as concretely impacting amyloid deposition and therefore potentially an important approach for therapeutic intervention in AD.

TargetHunter: An In Silico Target Identification Tool for Predicting Therapeutic Potential of Small Organic Molecules Based on Chemogenomic Database

Target identification of the known bioactive compounds and novel synthetic analogs is a very important research field in medicinal chemistry, biochemistry, and pharmacology. It is also a challenging and costly step towards chemical biology and phenotypic screening. In silico identification of potential biological targets for chemical compounds offers an alternative avenue for the exploration of ligand-target interactions and biochemical mechanisms, as well as for investigation of drug repurposing. Computational target fishing mines biologically annotated chemical databases and then maps compound structures into chemogenomical space in order to predict the biological targets. We summarize the recent advances and applications in computational target fishing, such as chemical similarity searching, data mining/machine learning, panel docking, and the bioactivity spectral analysis for target identification. We then described in detail a new web-based target prediction tool, TargetHunter (http://www.cbligand.org/TargetHunter). This web portal implements a novel in silico target prediction algorithm, the Targets Associated with its MOst SImilar Counterparts, by exploring the largest chemogenomical databases, ChEMBL. Prediction accuracy reached 91.1% from the top 3 guesses on a subset of high-potency compounds from the ChEMBL database, which outperformed a published algorithm, multiple-category models. TargetHunter also features an embedded geography tool, BioassayGeoMap, developed to allow the user easily to search for potential collaborators that can experimentally validate the predicted biological target(s) or off target(s). TargetHunter therefore provides a promising alternative to bridge the knowledge gap between biology and chemistry, and significantly boost the productivity of chemogenomics researchers for in silico drug design and discovery.

ChemInform Abstract: How Do the Fine Chemical, Pharmaceutical and Related Industries Approach Green Chemistry and Sustainability?

AbstractReview: 12 refs.

How do the fine chemical, pharmaceutical, and related industries approach green chemistry and sustainability?

Developing manufacturing processes for active pharmaceutical ingredients and intermediates often involves complex chemistry. All companies now aim to uphold the principles of green chemistry and sustainability as far as possible, but how effective are they in achieving this and how much variation is there from company to company? This perspective discusses the results of a survey carried out with 24 companies, including 11 “big pharma” companies and 6 “other pharma” companies. Companies from outside the pharma sector were also included to give a comparison with other areas of the fine chemical industry. These included two fine chemical manufacturers, one agrochemical manufacturer, and one flavour and fragrance company. The survey covered organisational aspects of green chemistry and sustainability, such as corporate policy and policy implementation, green chemistry and technologies, process metrics, and how the application of green issues changes through the various stages of development and whether there are different standards for low volume and/or high potency compounds.

Indoleamine 2,3-dioxygenase is the anticancer target for a novel series of potent naphthoquinone-based inhibitors.

Indoleamine 2,3-dioxygenase (IDO) is emerging as an important new therapeutic target for the treatment of cancer, chronic viral infections, and other diseases characterized by pathological immune suppression. While small molecule inhibitors of IDO exist, there remains a dearth of high-potency compounds offering in vivo efficacy and clinical translational potential. In this study, we address this gap by defining a new class of naphthoquinone-based IDO inhibitors exemplified by the natural product menadione, which is shown in mouse tumor models to have similar antitumor activity to previously characterized IDO inhibitors. Genetic validation that IDO is the critical in vivo target is demonstrated using IDO-null mice. Elaboration of menadione to a pyranonaphthoquinone has yielded low nanomolar potency inhibitors, including new compounds which are the most potent reported to date (K(i) = 61-70 nM). Synthetic accessibility of this class will facilitate preclinical chemical-genetic studies as well as further optimization of pharmacological parameters for clinical translation.

Spread of resistance to anticoagulant rodenticides in Germany

Resistance to anticoagulant rodenticides in Rattus norvegicus is now estimated to cover an area of roughly 26 000 km2 in northwest Germany. The chemical compounds involved are warfarin, coumatetralyl, bromadiolone and, to a lesser extent, difenacoum. Recent investigations revealed that the resistance area is extending considerably further east than was previously recorded. The easternmost populations containing resistant individuals are now present in the city of Hannover, whereas it seems that on the southern edge the urbanised Ruhr Basin remains mostly unaffected by resistance problems. Reported control failures with house mice (Mus musculus/domesticus) suggest that resistance to high potency compounds may occur, but these await scientific confirmation. We propose that molecular genetic testing methodology should be exploited to improve monitoring of anticoagulant resistance and provide more accurate information to users of rodenticides.

The effects of JWB1-84-1 on memory-related task performance by amyloid Aβ transgenic mice and by young and aged monkeys

JWB1-84-1 is one of 50 tertiary amine analogs of choline synthesized with expectation that they would be high potency compounds for cytoprotection. As one of the more potent analogs in this regard, JWB1-84-1, a piperazine derivative, was selected for testing as a cognition-enhancing agent. The compound was evaluated for efficacy in Alzheimer's disease transgenic mice (B6C3-Tg(APPswe, PSEN1dE9)85Dbo/J). A separate cohort of mice (AD Tg) were first subjected to a behavioral test battery in which the transgenic strain was compared with the wild-type strain. AD Tg mice were shown to exhibit specific deficits in the acquisition of a working memory (5-trial/session radial arm water maze, RAWM) task at a time when the animals exhibited maximal cerebral amyloid burden. JWB1-84-1 produced a dose-dependent decrease in the number of errors made by well trained AD-Tg mice the RAWM task that was maximal after the 20 μg/kg dose. Aged macaques (20–32 y) were trained to proficiency in their performance of a computer-assisted delayed matching-to-sample task. Vehicle (normal saline) or JWB1-84-1 (5–150 μg/kg, i.m.) was administered 10 min before the initiating of testing. On average, JWB1-84-1 treatment significantly improved task accuracy after all but the lowest dose. The maximal degree of improvement was attained after animals received the 100 μg/kg dose. The drug's effects were restricted primarily to Medium and Long delay trials – the most difficult portions of the task, which were improved by up to 18% above control. In young macaques JWB1-84-1 treatment also significantly reversed the decrements in task accuracy associated with the random presentation of a task distractor. Thus JWB1-84-1exhibits the potential for treating the cognitive symptoms associated with neurodegenerative diseases and attention deficit disorders. Its cytoprotective action might also work to slow the progression of Alzheimer's disease.