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Schistosomiasis is a neglected tropical disease caused by parasitic flatworms. Current treatment relies on just one partially effective drug, praziquantel (PZQ). Schistosoma mansoni Venus Kinase Receptors 1 and 2 (SmVKR1 and SmVKR2) are important for parasite growth and egg production, and are potential targets for combating schistosomiasis. VKRs consist of an extracellular Venus Flytrap Module (VFTM) linked via a transmembrane helix to a kinase domain. Here, we initiated a drug discovery effort to inhibit the activity of the SmVKR2 kinase domain (SmVKR2KD) by screening the GSK published kinase inhibitor set 2 (PKIS2). We identified several inhibitors, of which four were able to inhibit its enzymatic activity and induced phenotypic changes in ex vivoS. mansoni. Our crystal structure of the SmVKR2KD displays an active-like state that sheds light on the activation process of VKRs. Our data provide a basis for the further exploration of SmVKR2 as a possible drug target.

Radioactive iodine isotopes play a pivotal role in radiopharmaceuticals. Large-scale production of multi-patient dose of radioiodinated nuclear medicines requires high concentration of radioiodine. We demonstrate that tetrabutylammonium chloride and methyltrioctylamonium chloride are effective phase transfer reagents to concentrate iodide-124, iodide-125 and iodide-131 from the corresponding commercial water solutions. The resulting concentrated radioiodide, in the presence of either phase transfer reagent, does not hamper the chemical reactivity of aqueous radioiodide in the copper (II)-mediated one-pot three-component click chemistry to produce radioiodinated iodotriazoles.

Tumor cells become resistant to structurally or functionally unrelated chemotherapeutics which is called multidrug resistance (MDR). There are several mechanisms including the impairment of apoptotic pathway resulting in MDR development. NEK6 is a member of NIMA-related kinase family and it is an important mitotic kinase for proper cell cycle progression. Recent studies showed that NEK6 gene expression, protein level, and its kinase activity are increased in variety of cancer cells. We aimed to search the involvement of NEK6 in multidrug resistance and apoptosis in chronic myeloid leukemia. The expression levels of NEK6 and some of the apoptotic pathway genes such as BAX, BCL-2 and SURVIVIN were determined in sensitive and drug resistant subtypes of K652 chronic myeloid leukemia cell lines by RT-PCR method. siRNA silencing studies were performed to examine the effect of expression of NEK6 on apoptotic behavior in parental K-562 cell line. Cell viability assay was performed by XTT method in order to investigate whether NEK6 silencing leads to resistance in parental K-562 cells. NEK6 expression is significantly reduced in imatinib resistant K562 cells. After NEK6 gene is silenced by specific siRNA in parental K562 cell line, the expression levels of some apoptotic genes, such as BAX and SURVIVIN were found similar to drug resistant K562 cells. NEK6 may have potential role in imatinib resistance which may be through apoptotic pathway in chronic myeloid leukemia.

Developing and successfully implementing effective vaccination programs requires understanding the peculiarities of the people’s attitude towards vaccination. The prevalence of indecision regarding vaccination (understood as refusing or postponing vaccination despite the availability of vaccines) among the population can undermine the formation of collective immunity and compromise the effectiveness of vaccination programs. The goal of this work is to analyze the key factors influencing the people’s behavior and attitude towards vaccination. For this purpose, the authors review domestic and foreign studies devoted of the public behavior and attitude towards vaccination. As a result, three large groups of factors of population behavior in relation to vaccination are described: individual, organizational, and contextual. The most important socio-demographic predictors of readiness to be vaccinated are age and level of education. Such psychological features as the presence of cognitive distortions, intuitive thinking style, highly reactive temperament type contribute to indecision regarding vaccination. Other significant determinants of the readiness for vaccination are a high level of trust in the government, political actors, science and health authorities, social and interpersonal trust. In the context of the pandemic, concerns about the safety and effectiveness of vaccines and unknown long-term side effects have become the main reasons for hesitation regarding vaccination. At the same time, awareness about the vaccines and the diseases they prevent, the availability of reliable and transparent information is positively associated with the willingness to get vaccinated. The intention to get vaccinated will be higher if the perceived probability of COVID-19 infection is high and the expected consequences for one's own and others’ health and well-being are assessed as serious. Previous vaccination experience, the presence of those vaccinated against COVID-19 and/or those who have contracted the disease in one’s social environment can act as the incentives for vaccination. The most important organizational factors contributing to a positive attitude and desire to get vaccinated are the availability of vaccination services, high awareness of the vaccines and a positive attitude towards them on the part of medical professionals. At the same time, the short development time of the new vaccines, the novelty of some platforms carrying the COVID-19 vaccine antigen, contribute to indecision regarding vaccination. Contextual factors include historical, political, and socio-cultural factors, as well as the state of the communication and information environment.&nbsp

We present a group contribution method (SoluteGC) and a machine learning model (SoluteML) to predict the Abraham solute parameters, as well as a machine learning model (DirectML) to predict solvation free energy and enthalpy at 298 K. The proposed group contribution method uses atom-centered functional groups with corrections for ring and polycyclic strain while the machine learning models adopt a directed message passing neural network. The solute parameters predicted from SoluteGC and SoluteML are used to calculate solvation energy and enthalpy via linear free energy relationships. Extensive data sets containing 8366 solute parameters, 20,253 solvation free energies, and 6322 solvation enthalpies are compiled in this work to train the models. The three models are each evaluated on the same test sets using both random and substructure-based solute splits for solvation energy and enthalpy predictions. The results show that the DirectML model is superior to the SoluteML and SoluteGC models for both predictions and can provide accuracy comparable to that of advanced quantum chemistry methods. Yet, even though the DirectML model performs better in general, all three models are useful for various purposes. Uncertain predicted values can be identified by comparing the three models, and when the 3 models are combined together, they can provide even more accurate predictions than any one of them individually. Finally, we present our compiled solute parameter, solvation energy, and solvation enthalpy databases (SoluteDB, dGsolvDBx, dHsolvDB) and provide public access to our final prediction models through a simple web-based tool, software packages, and source code. ispartof: JOURNAL OF CHEMICAL INFORMATION AND MODELING vol:62 issue:3 pages:433-446 ispartof: location:United States status: published

The nasal epithelium is an important target for drug delivery to the nose and secondary organs such as the brain via the olfactory bulb. For both topical and brain delivery, the targeting of specific nasal regions such as the olfactory epithelium (brain) is essential, yet challenging. In this study, a numerical model was developed to predict the regional dose as mass per surface area (for an inhaled mass of 2.5 mg), which is the biologically most relevant dose metric for drug delivery in the respiratory system. The role of aerosol diameter (particle diameter: 1 nm to 30 µm) and inhalation flow rate (4, 15 and 30 L/min) in optimal drug delivery to the vestibule, nasal valve, olfactory and nasopharynx is assessed. To obtain the highest doses in the olfactory region, we suggest aerosols with a diameter of 20 µm and a medium inlet air flow rate of 15 L/min. High deposition on the olfactory epithelium was also observed for nanoparticles below 1 nm, as was high residence time (slow flow rate of 4 L/min), but the very low mass of 1 nm nanoparticles is prohibitive for most therapeutic applications. Moreover, high flow rates (30 L/min) and larger micro-aerosols lead to highest doses in the vestibule and nasal valve regions. On the other hand, the highest drug doses in the nasopharynx are observed for nano-aerosol (1 nm) and fine microparticles (1-20 µm) with a relatively weak dependence on flow rate. Furthermore, using the 45 different inhalation scenarios generated by numerical models, different machine learning models with five-fold cross-validation are trained to predict the delivered dose and avoid partial differential equation solvers for future predictions. Random forest and gradient boosting models resulted in R2 scores of 0.89 and 0.96, respectively. The aerosol diameter and region of interest are the most important features affecting delivered dose, with an approximate importance of 42% and 47%, respectively. ispartof: PHARMACEUTICALS vol:16 issue:1 ispartof: location:Switzerland status: published

Background The molecular chaperone, Hsp90, is a key player in the protein quality control system that maintains homeostasis under cellular stress conditions. It is a homodimer with ATP-dependent activity, and is a prominent member of the chaperone machinery that stabilizes, matures and (re)folds an extensive list of client proteins. Hsp90 occurs as four isoforms, cytosolic Hsp90α and Hsp90β, mitochondrial TRAP1 and Grp94 present in the endoplasmic reticulum. An aberrant role of Hsp90 has been attributed to several cancers and neurodegenerative disorders. Consequently, Hsp90 has emerged as an attractive therapeutic target. However, pan-Hsp90 inhibition often leads to detrimental dose-limiting toxicities. Novel strategies for Hsp90-targeted therapy intend to avoid this by using isoform-specific Hsp90 inhibition. In this respect, the radiosynthesis of carbon-11 labeled SNX-ab was developed and [11C]SNX-ab was evaluated as a Hsp90α,β isoform-selective PET probe, which could potentially allow to quantify in vivo Hsp90α,β expression. Results [11C]SNX-ab was synthesized with excellent radiochemical yields of 45% and high radiochemical purity (> 98%). In vitro autoradiography studies on tissue slices of healthy mouse brain, mouse B16.F10 melanoma and U87 glioblastoma using homologous (SNX-ab, SNX-0723) and heterologous (Onalespib and PU-H71) Hsp90 inhibitors demonstrated only limited reduction of tracer binding, indicating that the binding of [11C]SNX-ab was not fully Hsp90-specific. Similarly, [11C]SNX-ab binding to U87 cells was not efficiently inhibited by Hsp90 inhibitors. Ex vivo biodistribution studies in healthy mice revealed limited brain exposure of [11C]SNX-ab and predominantly hepatobiliary clearance, which was confirmed by in vivo full-body dynamic µPET studies. Conclusion Our results suggest that [11C]SNX-ab is not an ideal probe for in vivo visualization and quantification of Hsp90α/β expression levels in tumour and brain. Future research in the development of next-generation Hsp90 isoform-selective PET tracers is warranted to dissect the role played by each isoform towards disease pathology and support the development of subtype-specific Hsp90 therapeutics.

Abstract: Some novel triazole-bearing ketone and oxime derivatives were synthesized from Ibuprofen. In vitro cytotoxic activities of all synthesized molecules against five cancer lines (human breast cancer MCF-7, human lung cancer A549, human prostate cancer PC-3, human cervix cancer HeLa, and human chronic myelogenous leukemia K562 cell lines) were evaluated by MTT assay. In addition, mouse embryonic fibroblast cells (NIH/3T3) were also evaluated to determine the selectivity. Compounds 18, 36, and 45 were found to be the most cytotoxic, and their IC50 values were in the range of 17.46–68.76 µM, against the tested cancer cells. According to the results, compounds 7 and 13 demonstrated good anti-inflammatory activity against the microsomal enzyme prostaglandin E2 synthase-1 (mPGES-1) enzyme at IC50 values of 13.6 and 4.95 µM. The low cytotoxicity and non-mutagenity of these compounds were found interesting. Also, these compounds significantly prevented tube formation in angiogenesis studies. In conclusion, the anti-inflammatory and angiogenesis inhibitory activities of these compounds without toxicity suggested that they may be promising agents in anti-inflammatory treatment and they may be supportive agents for the cancer treatment. Graphical abstract: [Figure not available: see fulltext.].

The soluble epoxide hydrolase (sEH) has been suggested as a pharmacological target for the treatment of several diseases, including pain-related disorders. Herein, we report further medicinal chemistry around new benzohomoadamantane-based sEH inhibitors (sEHI) in order to improve the drug metabolism and pharmacokinetics properties of a previous hit. After an extensive in vitro screening cascade, molecular modeling, and in vivo pharmacokinetics studies, two candidates were evaluated in vivo in a murine model of capsaicin-induced allodynia. The two compounds showed an anti-allodynic effect in a dose-dependent manner. Moreover, the most potent compound presented robust analgesic efficacy in the cyclophosphamide-induced murine model of cystitis, a well-established model of visceral pain. Overall, these results suggest painful bladder syndrome as a new possible indication for sEHI, opening a new range of applications for them in the visceral pain field., Spanish Government SAF2017-82771-R RTI2018-093955-B-C21 PGC2018-102192-B-I00 RTI2018-101032-J-I00 Spanish MCIN/AEI, ERDF A way of making Europe - MCIN/AEI PID2020-118127RB-I00, PID2019-106285RB, ERDF A way of making Europe, Xunta de Galicia, European Commission ED431G 2019/02, ED431C 2018/21, Fundacio Bosch i Gimpera, Universitat de Barcelona (F2I grant) Generalitat de Catalunya 2017 SGR 106 2017 SGR 1707, European Research Council (ERC) European Commission ERC-2015-StG-679001-NetMoDEzyme European Commission MSCA-IF-2014-EF661160-MetAccembly, Universitat de Barcelona (APIF grant), Spanish Society of Medicinal Chemistry (SEQT) and Lilly FWO 12Y0720N, Ministry of Science and Innovation, Spain (MICINN) Spanish Government RYC2020-029552-I, United States Department of Health & Human Services, National Institutes of Health (NIH) - USA R35 ES03443 P42 ES004699, United States Department of Health & Human Services National Institutes of Health (NIH) - USA NIH National Institute of Neurological Disorders & Stroke (NINDS) R01 DK107767 United States Department of Health & Human Services National Institutes of Health (NIH) - USA NIH National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK) R01 DK103616

Serum albümin, kan plazmasında en yaygın bulunan proteinlerden biridir. Ozmotik basıncın ayarlanması,kan pH’nın belirlenmesi ve serbest radikallerin azaltılması gibi birçok farklı fizyolojik görevlerinin yanı sırakanda bulunan endojen ve eksojen maddelerin (yağ asitleri, ilaçlar ve metabolitler vb.) taşınmasında birincilişlevi olan çok fonksiyonlu ve önemli bir proteindir. İlaçlar hedeflerine ulaşmak için kan plazmasındataşınırken kaçınılmaz olarak serum albümin ile etkileşime girmektedirler. Serum albümin ile ilaç etkileşimiilacın terapötik etkisi hakkında bilgi vermektedir. Bu etkileşimlerin incelenmesi ilaç kimyasında, tıpta,biyoteknolojide ve biyokimyada önemli bir araştırma alanıdır. Sığır serum albümin (BSA), 582 amino asitkalıntısından oluşan ve insan serum albümini ile %76 benzerliği olan bir proteindir. Düşük maliyetli olması,yaygın olarak bulunabilmesi ve saflaştırma işleminin kolay olması nedeniyle BSA, araştırmacılar tarafındanligandların proteine bağlanma çalışmaları için sıklıkla tercih edilen, protein-ilaç etkileşimleri ve bağlanmamekanizmalarının belirlenmesi için model olan bir taşıma sistemidir. Kumarinler bir benzen halkası ilebir α-piron halkasının kaynaşması sonucu oluşan benzopiron adı verilen bir bileşik sınıfının üyesidirler.Doğal olarak bitkilerde bulunabildiği gibi sentetik olarak da elde edilebilmektedir. Kumarinlerin sahipoldukları konjuge çift halka sistemleri, onları farklı araştırma alanları için ilginç moleküller haline getirmiştir.Kumarin türevleri geniş bir biyolojik aktivite yelpazesi sergilemektedirler. Bunlar arasında anti-oksidan,anti-enflamatuar, anti-bakteriyel, anti-viral, anti-tümör ve anti-koagülan özellikleri öne çıkmaktadır.Kumarinler tıpta ve özellikle ilaç endüstrisinde yaygın olarak kullanılmaktadırlar. Çalışmamızda uygunEmilim, Dağılım, Metabolizma ve Atılım (ADME) özelliklerine göre farmakokinetik ve farmakodinamiketkileri iyi olan daha önceden sentezlenmiş ve karakterize edilmiş kumarin türevlerinin BSA’ya bağlanmalarıve taşınmaları in silico ve in vitro yöntemlerle araştırılmıştır. In silico çalışmalarda moleküler yerleştirme(moleküler docking) ve in vitro çalışmalarda UV-vis absorbans, floresans gibi multi-spektroskopik yöntemlerkullanılmıştır. BSA ile kumarin türevlerinin etkileşimleri in silico ve in vitro yöntemlerle aydınlatılmıştır. Insilico çalışmalar sonucunda kumarinlerin bağlanma enerjileri, ligand verimliliği değerleriyle birlikte proteinligandetkileşimleri ve konformasyonları belirlenmiştir. Ayrıca in vitro multi-spektroskopik analizlerindeğerlendirilmesiyle; bileşikler BSA’nın floresans şiddetinde, absorbansında ve ikincil yapısında değişikliklerizlenmiş, kuençleşme mekanizmaları, bağlanma sabitleri ve bağlanma bölgelerinin sayıları belirlenmiştir.

Nitrik oksit (NO), gaz halinde bulunan bir sinyal molekülüdür. Nitrik oksit sentazlar (NOS) ise, arjininden nitrik oksit sentezleyen enzimlerdir. Nitrik oksit sentazın (NOS) insanda 3 izoformu bulunmaktadır. Bunlardan nöronal nitrik oksit sentaz (nNOS) ve endotelyal nitrik oksit sentaz (eNOS) NO üretimi üzerinde etkili iken, indüklenebilir nitrik oksit sentaz (iNOS) ise patojenlere karşı bağışıklık işlemlerinde etkili olurlar.Bu üç enzimde birbirine çok yakın bir yapıya sahiptir. Bu yüzden seçimli inhibitörlerin belirlenebilmesi için farklı ligandlar kullanılarak enzimlerin aktif bölgelerindeki farkları incelemek gerekmektedir. Nöronal nitrik oksit sentazın seçimli inhibisyonu, sinir sistemi üzerinde etkili olan Parkinson ve Alzheimer gibi hastalıklara karşı umut verici tedavi yaklaşımı olarak ortaya çıkmaktadır.Kumarinler, 1,2-benzopiron (C9H6O2) olarak karakterize edilen ve yaygın olarak bitkilerde bulunan doğal ürünlerdir. Ayrıca, bitkiler dışında sentetik olarak üretilmekte olup, bazı bakteri ve mantar türlerinde bulunurlar. Kumarinler, geniş bir yelpazede farklı farmakolojik özellikler göstermektedir. Literatürde kumarin türevlerinin; anti-koagülanlar, anti-HIV ajanları, anti-oksidanlar, anti-tümörler ve serbest radikal temizleyicileri olarak farmakolojik olarak yararlı olduğu ve endüstriyel alanlarda geniş uygulamalara sahip olduğu bilinmektedir. Bu çalışmamızda çeşitli kumarin bileşiklerin nitrik oksit sentaz izoenzimleri üzerindeki etkilerinin moleküler doking yoluyla in siliko olarak incelenmiştir. Ayrıca bu çalışmada kullanılan kumarin bileşiklerinin Emilim, Dağılım, Metabolizma ve Atılım (ADME) özellikleri ve Lipinski 5 kuralına uygunluğu da araştırılmıştır. Bu duruma uygun olan kumarin bileşikleri protein veri bankasından indirilen enzimlerle moleküler doking çalışmaları gerçekleştirilmiş ve bu enzimlere bağlanma durumları incelenmiştir. Moleküler doking sonucunda nNOS enzimine bağlanma afinitesi güçlü olan kumarin türevleri ileride Parkinson ve Alzheimer gibi sinir sistemini etkileyen hastalıklara karşı yeni ilaçların geliştirilmesinde katkıda bulunabileceği düşünülmektedir.

The scientific report presents the results of a study of various approaches to the construction of modern quality management systems in medical organizations. Trends in the development of healthcare systems in the world and in the Russian Federation are analyzed, it is shown what role, on the one hand, the development of the infrastructure of medical care for the population, the staff of medical organizations, and on the other hand, the satisfaction of patients with the quality of the services provided to them by the medical organization, plays.

Ten-eleven translocation dioxygenases (TETs) are the erasers of 5-methylcytosine (mC), the central epigenetic regulator of mammalian DNA. TETs convert mC to three oxidized derivatives with unique physicochemical properties and inherent regulatory potential, and it initializes active demethylation by the base excision repair pathway. Potent small molecule inhibitors would be useful tools to study TET functions by conditional control. To facilitate the discovery of such tools, we here report a high-throughput screening pipeline and its application to screen and validate 31.5k compounds for inhibition of TET2. Using a homogenous fluorescence assay, we discover a novel quinoline-based scaffold that we further validate with an orthogonal semi-high throughput MALDI-MS assay for direct monitoring of substrate turnover. Structure–activity relationship (SAR) studies involving >20 derivatives of this scaffold led to the identification of optimized inhibitors, and together with computational studies suggested a plausible model for its mode of action., RSC medicinal chemistry;13(12)

Minor structural modifications of acyclic nucleoside phosphonates can dramatically affect their antiviral properties. This work discloses a shift in the selectivity spectrum of 3-hydroxy-2-(phosphonomethoxy)propyl (HPMP) nucleotides from herpesviruses toward hepatitis B virus (HBV) induced by their acyclic chain 2-substitution with a nonpolar group. Two series of racemic (R,S)-2-methyl-3-hydroxy-2-(phosphonomethoxy)propyl (MHPMP) and (R,S)-2-ethynyl-3-hydroxy-2-(phosphonomethoxy)propyl (EHPMP) nucleotides were initially synthesized. Among these, guanine-containing derivatives exhibited significant anti-HBV activities in the submicromolar range. Enantioenriched MHPMPG and EHPMPG analogues were subsequently obtained by Sharpless asymmetric epoxidation. The (S)-enantiomers possessed an 8- to 26-fold higher potency than the relative (R)-forms. A further comparison of the EC90 values indicated that (S)-EHPMPG inhibited HBV replication more effectively than its 2-methyl analogue. A phosphonodiamidate prodrug of (S)-EHPMPG was thus prepared and found to exert a remarkably high anti-HBV activity (EC50 = 9.27 nM) with excellent selectivity (SI50 > 10,787), proving to be a promising candidate for anti-HBV drug development. ispartof: JOURNAL OF MEDICINAL CHEMISTRY vol:65 issue:13 ispartof: location:United States status: Published online

The substantial impact of acyclic nucleoside phosphonates (ANPs) on human medicine encourages the synthesis of new ANP analogues with a potentially differentiated antiviral spectrum. Herein, we demonstrate the functionalization of the 2-position of the (R,S)-3-hydroxy-2-(phosphonomethoxy)propyl side-chain of an inactive ANP with a polar cyano group to generate a thymine analogue with selective inhibition of hepatitis B virus (HBV) replication (SI > 302; EC50 = 0.33 μM), without significant antiretroviral activity. These findings suggest new strategies to synthesize unique ANPs with a targeted antiviral profile. ispartof: RSC MEDICINAL CHEMISTRY vol:12 issue:5 pages:804-808 ispartof: location:England status: published

Malarial parasites employ actin dynamics for motility, and any disruption to these dynamics renders the parasites unable to effectively establish infection. Therefore, actin presents a potential target for malarial drug discovery, and naturally occurring actin inhibitors such as latrunculins are a promising starting point. However, the limited availability of the natural product and the laborious route for synthesis of latrunculins have hindered their potential development as drug candidates. In this regard, we recently described novel truncated latrunculins, with superior actin binding potency and selectivity towards P. falciparum actin than the canonical latrunculin B. In this paper, we further explore the truncated latrunculin core to summarize the SAR for inhibition of malaria motility. This study helps further understand the binding pattern of these analogues in order to develop them as drug candidates for malaria.

Chemical probes that covalently modify cysteine residues in a protein‐specific manner are valuable tools for biological investigations. Covalent fragments are increasingly implemented as probe starting points, but the complex relationship between fragment structure and binding kinetics makes covalent fragment optimization uniquely challenging. We describe a new technique in covalent probe discovery that enables data‐driven optimization of covalent fragment potency and selectivity. This platform extends beyond the existing repertoire of methods for identifying covalent fragment hits by facilitating rapid multiparameter kinetic analysis of covalent structure–activity relationships through the simultaneous determination of K i, k inact and intrinsic reactivity. By applying this approach to develop novel probes against electrophile‐sensitive kinases, we showcase the utility of the platform in hit identification and highlight how multiparameter kinetic analysis enabled a successful fragment‐merging strategy., Breaking into fragments: A biophysical platform for determining the complex structure–activity relationships of covalent fragments. By using this approach, a novel series of covalent fragments has been identified for targeting electrophile‐sensitive kinases; optimization is facilitated by covalent fragment merging.

Taking the previously reported compound BH-7d as the lead, we designed and synthesized a series of piperidinyl-substituted [1,2,4]triazolo[1,5-a]pyrimidines, and their anti-HIV activities as well as cytotoxicities were evaluated. Several compounds exhibited moderate anti-HIV (IIIB) potency, among which 2b was the most active one (EC50 = 4.29 μM). Structure-activity relationships derived from the antiretroviral results were analyzed. Additionally, most compounds demonstrated reduced cytotoxicity (CC50 > 200 μM) compared with those of BH-7d and etravirine. Molecular docking study further revealed the binding conformation of 2b in the binding pocket of HIV-1 reverse transcriptase. ispartof: CHEMICAL BIOLOGY & DRUG DESIGN vol:97 issue:1 pages:67-76 ispartof: location:England status: published

On June 8, 2018, an NS3/4A protease inhibitor called danoprevir was approved in China to treat the infections of HCV genotype (GT) 1b - the most common HCV genotype worldwide. Based on phase 2 and 3 clinical trials, the 12-week regimen of ritonavir-boosted danoprevir (danoprevir/r) plus peginterferon alpha-2a and ribavirin offered 97.1% (200/206) of sustained virologic response at post-treatment week 12 (SVR12) in treatment-naïve non-cirrhotic patients infected with HCV genotype 1b. Adverse events such as anemia, fatigue, fever, and headache were associated with the inclusion of peginterferon alpha-2a and ribavirin in the danoprevir-based regimen. Moreover, drug resistance to danoprevir could be traced to amino acid substitutions (Q80K/R, R155K, D168A/E/H/N/T/V) near the drug-binding pocket of HCV NS3 protease. Despite its approval, the clinical use of danoprevir is currently limited to its combination with peginterferon alpha-2a and ribavirin, thereby driving its development towards interferon-free, ribavirin-free regimens with improved tolerability and adherence. In the foreseeable future, pan-genotypic direct-acting antivirals with better clinical efficacy and less adverse events will be available to treat HCV infections worldwide. ispartof: DRUG DESIGN DEVELOPMENT AND THERAPY vol:14 pages:2759-2774 ispartof: location:New Zealand status: published

Three series of amidate prodrugs of O-2-alkylated acyclic nucleosides of the 3-fluoro-2-(phosphonomethoxy)propyl (FPMP), cyclic 3-hydroxy-2-(phosphonomethoxypropyl) (cHPMP), and 2-(phosphonomethoxypropyl) (PMP)-type featuring cytosine and 5-fluorocytosine as nucleobases were readily synthesized. Both the aspartic acid ester and valine ester prodrugs of (R)-O-2-alkylated FPMPC exhibited potent anti-HCMV and VZV activity in the micromolar range. In addition, the valine ester prodrugs of 5-fluorocytosine (R)-O-2-alkylated FPMP and (R)-O-2-alkylated cHPMPC showed inhibitory activity at molar concentrations against these viruses. ispartof: ACS MEDICINAL CHEMISTRY LETTERS vol:11 issue:7 pages:1410-1415 ispartof: location:United States status: published

The success of metal‐based anticancer therapeutics in the treatment of cancer is best exemplified by cisplatin. Currently used in 32/78 cancer regimens, metal‐based drugs have a clear role in cancer therapy. Despite this, metal‐based anticancer therapeutics are not without drawbacks, with issues such as toxic side effects and the development of resistance mechanisms. This has led to investigations of other metal‐based drug candidates such as auranofin, a gold‐based drug candidate as well as ruthenium‐based candidates, NAMI‐A, NKP‐1339 and TLD‐1433. All are currently undergoing clinical trials. Another class of complexes under study are rhenium‐based; such complexes have undergone extensive in vitro testing but only nine have been reported to display antitumour in vivo activity, which is a necessary step before entering clinical trials. This review will document, chronologically, the rhenium‐based drug candidates that have undergone in vivo testing and the outlook for such complexes., Beyond cisplatin: The use of animal models, otherwise known as in vivo testing, is a crucial step in drug development. To date there have only been nine reported cases of rhenium‐based complexes undergoing in vivo testing. This concept article explores the history of these complexes.

Background The development of radiopharmaceuticals requires extensive evaluation before they can be applied in a diagnostic or therapeutic setting in Nuclear Medicine. Chemical, radiochemical, and pharmaceutical parameters must be established and verified to ensure the quality of these novel products. Main body To provide supportive evidence for the expected human in vivo behaviour, particularly related to safety and efficacy, additional tests, often referred to as “non-clinical” or “preclinical” are mandatory. This document is an outcome of a Technical Meeting of the International Atomic Energy Agency. It summarises the considerations necessary for non-clinical studies to accommodate the regulatory requirements for clinical translation of radiopharmaceuticals. These considerations include non-clinical pharmacology, radiation exposure and effects, toxicological studies, pharmacokinetic modelling, and imaging studies. Additionally, standardisation of different specific clinical applications is discussed. Conclusion This document is intended as a guide for radiopharmaceutical scientists, Nuclear Medicine specialists, and regulatory professionals to bring innovative diagnostic and therapeutic radiopharmaceuticals into the clinical evaluation process in a safe and effective way.

Biological medicinal products have revolutionised the treatment of many diseases, e [...]. ispartof: PHARMACEUTICALS vol:15 issue:5 ispartof: location:Switzerland status: published

RAS is a major anticancer drug target which requires membrane localization to activate downstream signal transduction. The direct inhibition of RAS has proven to be challenging. Here, we present a novel strategy for targeting RAS by stabilizing its interaction with the prenyl-binding protein PDE6D and disrupting its localization. Using rationally designed RAS point mutations, we were able to stabilize the RAS:PDE6D complex by increasing the affinity of RAS for PDE6D, which resulted in the redirection of RAS to the cytoplasm and the primary cilium and inhibition of oncogenic RAS/ERK signaling. We developed an SPR fragment screening and identified fragments that bind at the KRAS:PDE6D interface, as shown through cocrystal structures. Finally, we show that the stoichiometric ratios of KRAS:PDE6D vary in different cell lines, suggesting that the impact of this strategy might be cell-type-dependent. This study forms the foundation from which a potential anticancer small-molecule RAS:PDE6D complex stabilizer could be developed. ispartof: JOURNAL OF MEDICINAL CHEMISTRY vol:65 issue:3 pages:1898-1914 ispartof: location:United States status: published

Integral membrane proteins pose considerable challenges to high resolution structural analysis. Maintaining membrane proteins in their native state during protein isolation is essential for structural study of these bio-macromolecules. Detergents are the most commonly used amphiphilic compounds for stabilizing membrane proteins in solution outside a lipid bilayer. We previously introduced a glyco-diosgenin (GDN) detergent that was shown to be highly effective at stabilizing a wide range of membrane proteins. This steroidal detergent has additionally gained attention due to its compatibility with membrane protein structure study via cryo-EM. However, synthetic inconvenience limits widespread use of GDN in membrane protein study. To improve its synthetic accessibility and to further enhance detergent efficacy for protein stabilization, we designed a new class of glyco-steroid-based detergents using three steroid units: cholestanol, cholesterol and diosgenin. These new detergents were efficiently prepared and showed marked efficacy for protein stabilization in evaluation with a few model membrane proteins including two G protein-coupled receptors. Some new agents were not only superior to a gold standard detergent, DDM (n-dodecyl-β-d-maltoside), but were also more effective than the original GDN at preserving protein integrity long term. These agents represent valuable alternatives to GDN, and are likely to facilitate structural determination of challenging membrane proteins.

In the past two decades, significant efforts have been put into designing small molecules to target selected genomic sites where DNA conformational rearrangements control gene expression. G-rich sequences at oncogene promoters are considered good points of intervention since, under specific environmental conditions, they can fold into non-canonical tetrahelical structures known as G-quadruplexes. However, emerging evidence points to a frequent lack of correlation between small molecule targeting of G-quadruplexes at gene promoters and the expression of the associated protein, which hampers pharmaceutical applications. The wide genomic localization of G-quadruplexes along with their highly polymorphic behavior may account for this scenario, suggesting the need for more focused drug design strategies. Here, we will summarize the G4 structural features that can be considered to fulfill this goal. In particular, by comparing a telomeric sequence with the well-characterized G-rich domain of the KIT promoter, we will address how multiple secondary structures might cooperate to control genome architecture at a higher level. If this holds true, the link between drug-DNA complex formation and the associated cellular effects will need to be revisited. ispartof: PHARMACEUTICALS vol:15 issue:3 ispartof: location:Switzerland status: published