Structure-activity relationship of Lycium barbarum polysaccharides / 中国中药杂志

As a traditional Chinese herb and functional food, the fruits of Lycium barbarum has been widely used for thousands of years in China. L. barbarum polysaccharides(LBPs) are predominant active components, which have immunomodulatory, antioxidant, hypoglycemic, neuroprotective, anti-tumor, and prebiotic activities. The molecular weight, monosaccharide composition, glycosidic bond, branching degree, protein content, chemical modification, and spatial structure of LBPs are closely related to their biological activity. Based on the previous studies of this research team, this paper systematically combed and integrated the research progress of structure, function, and structure-activity relationship of LBPs. At the same time, some problems restricting the clarification of the structure-activity relationship of LBPs were considered and prospected, hoping to provide references for the high value utilization of LBPs and in-depth exploration of their health value.

Design, synthesis and biological evaluation of 8-hydroxyquinoline derivatives as potential clostridium difficile antibiotics / 药学实践杂志

Objective To find a more effective alternative therapy for antibiotic therapy and fecal microbiota transplantation in current primary treatment of clostridioides difficile infection (CDI) because of the high recurrence rate. Methods A series of 8-hydroxyquinoline derivatives were designed and synthesized based on 8-hydroxyquinoline scarffold. Results The activity test against C. difficile showed that most of the molecules exhibited good antibacterial activity against C. difficile, and compound 6f showed attractive anti-C. difficile activity. Conclusion A new type of 8-hydroxyquinoline derivatives with anti-clostridium difficile was found, which could be used as good lead compounds for further development.

Research progress on efflux pump inhibitors of Mycobacterium tuberculosis in recent years / 药学学报

Currently, the resistance of first-line anti-tuberculosis drugs has made the prevention and treatment of tuberculosis increasingly difficult, posing a serious threat to global public health. Several studies have shown that efflux pumps are one of the important causes for bacteria to develop multi-drug resistance and extremely-drug resistance, and efflux pump inhibitors can inhibit the efflux of antibacterial drugs, thereby reducing bacterial drug resistance. Numerous natural products and synthetic compounds have been reported to possess efflux pump inhibitory activity, but they have not been applied in clinical settings because of their toxicity, pharmacokinetic properties, etc. Therefore, we summarized the efflux pump inhibitory activity, antimicrobial activity, and structure-activity relationships of reported efflux pump inhibitors against Mycobacterium tuberculosis in recent years, providing references for the development of new efflux pump inhibitors with better activity and lower toxicity.

Research advances in the study of anticoagulant active molecules / 药学学报

The incidence of thrombosis-induced cardiovascular diseases is increasing worldwide and poses a serious threat to human health. Three factors, slow speed of blood flow, hypercoagulable blood and vascular damage, have been considered to be causes of thrombosis. Antithrombotic drugs have been classified into three categories based on the mechanism of thrombosis, including anticoagulants, platelet inhibitors and fibrinolytics. The coagulation and anticoagulation systems have drawn increasing attention because of the important role they play in the process of thrombosis. Novel compounds with anticoagulant activity are now emerging, alleviating to some extent some of the problems associated with the clinical use of early approved thrombotic drugs, such as high bleeding risk, slow onset of action and narrow therapeutic windows. In this review, we initially describe the mechanisms of coagulation as well as thrombosis. Meanwhile, a wide range of bioactive compounds and potential antithrombotic candidates reported in recent years have been summarized. In addition, the structure-activity relationship of certain compounds has been discussed, expecting to facilitate the development of molecules with anticoagulant biological activity for the treatment of thrombotic diseases.

Prediction of concentration immediately dangerous to life or health of benzene and its derivatives based on quantitative structure-activity relationship / 环境与职业医学

Background With the increasing exposure to hazardous chemicals in the workplace and frequency of occupational injuries and occupational safety accidents, the acquisition of occupational exposure limits of hazardous chemicals is imminent. Objective To obtain more unknown immediately dangerous to life or health (IDLH) concentrations of hazardous chemicals in the workplace by exploring the application of quantitative structure-activity relationship (QSAR) prediction method to IDLH concentrations, and to provide a theoretical basis and technical support for the assessment and prevention of occupational injuries. Methods QSAR was used to correlate the IDLH values of 50 benzene and its derivatives with the molecular structures of target compounds. Firstly, affinity propagation algorithm was applied to cluster sample sets. Secondly, Dragon 2.1 software was used to calculate and pre-screen 537 molecular descriptors. Thirdly, the genetic algorithm was used to select six characteristic molecular descriptors as dependent variables and to construct a multiple linear regression model (MLR) and two nonlinear models using support vector machine (SVM) and artificial neural network (ANN) respectively. Finally, model performance was evaluated by internal and external validation and Williams diagram was drawn to determine the scopes of selected models. Results The ANN model results showed that \begin{document}$ {R}_{\mathrm{t}\mathrm{r}\mathrm{a}\mathrm{i}\mathrm{n}}

Design, synthesis and biological activity of DB02 amino acid derivatives as HIV-1 non-nucleoside reverse transcriptase inhibitors / 药学学报

To improve the stability of amino acid ester derivatives of DB02, a series of 24 amide derivatives of DB02 amino acids as non-nucleoside HIV-1 reverse transcriptase inhibitor were designed and synthesized based on bioisosterism by replacing amino acid ester scaffold with more stable amide bond. The anti-HIV-1 activity of these compounds was evaluated by MTT assay and counting the number of syncytia. Most of the target compounds showed a potential anti-HIV-1 activity, among which compounds 2d, 2i, 2l, 2s, and 2w had better antiviral effect than lead compound DB02, with a therapeutic index > 1 000.00. Finally, the structure-activity relationship of these compounds was discussed, which provided new ideas for the further development of DB02 derivatives.

Oral absorption and effect of macromolecules in traditional Chinese medicine: a new perspective and research mode of phase structure / 中国中药杂志

Protein polypeptides and polysaccharides, the indispensable macromolecular active components in traditional Chinese medicine, are widely found in Chinese medicine decoction after the decoction of traditional Chinese medicine. However, through oral administration, these macromolecules are digested by the stomach and intestine and thus fail to be absorbed in prototype. This is inconsistent with the actual clinical efficacy of Chinese medicine decoction. According to modern research, new phase structures and effects of the macromolecules emerge during the decoction of traditional Chinese medicine, but the phase change law caused by the interaction among the components of traditional Chinese medicine and the relationship between phase structure and effect are still unclear. Thus, this study reviewed the oral absorption of macromolecular components of traditional Chinese medicine, analyzed the internal relationship of the form of macromolecules in traditional Chinese medicine with the absorption and effect based on phase structure, and summarized the research mode of oral absorption and effect of macromolecules in traditional Chinese medicine with phase structures as the core, providing new ideas and methods for future research.

Research progress of small molecule proteasome activators / 药学学报

Proteasome controls the degradation of proteins closely related to life activities and plays a key role in the maintenance of protein homeostasis. Proteasome activities decrease with aging, followed by the overwhelming production of damaged proteins which far exceed the protein consumption. Accumulation of these proteins leads to various diseases including neurodegenerative diseases. Therefore, inducing toxic protein degradation is considered as a promising solution for the treatment of these diseases, while increasing the activity of proteasome is considered as an important strategy. However, the research in this field is still in the preliminary stage, and this review will focus on the discussion of the research progress of various small molecule proteasome activators, including research methods, pharmacological effects, structure-activity relationships and the existing problems.

Applications of QSAR in Toxicological Risk Assessment of Medical Devices / 中国医疗器械杂志

The chemical characterization analysis of a medical device often results in chemical substances with unknown toxicities. While identification of each individual toxicity could result in a time-consuming hurdle with tremendous labor and financial burden, quantitative structure-activity relationship (QSAR) is of great significance for toxicity risk assessment of such chemical substances. By establishing quantitative relationship between the molecular structures or active groups of similar chemical compounds with their biological activities, QSAR can be utilized to predict the toxicity of such target compounds with significantly reduced cost and time. In this article, the authors generally summarized the mechanisms of QSAR approaches, current applications of QSAR modeling in the field of medical device, an introduction of the characteristics of publicly and commercially-available QSAR software, and briefly explored future trends of QSAR modeling in medical device toxicological risk assessment. The utilization of QSAR would undoubtedly further advance the toxicological risk assessment of medical devices.

Application value of magnetic resonance T2mapping in the diagnosis of knee osteoarthritis / 中国基层医药

Objective:To investigate the application value of magnetic resonance T2mapping in the diagnosis of knee osteoarthritis (KOA).Methods:The MRI data of the knees of 148 patients with KOA who underwent diagnosis and treatment between January 2017 and December 2020 in Benxi Central Hospital (KOA group) and 30 healthy volunteers (control group) were retrospectively analyzed. T2 values of cartilage in each sub-region of the knee were measured, grouped, and statistically analyzed.Results:There was no significant difference in the T2 value of cartilage in each sub-region of the knee between male and female patients in mild and severe KOA groups (all P > 0.05). T2 values in the medial anterior, middle, and posterior areas of the tibia, lateral anterior, middle and posterior areas of the tibia, medial middle, posterior and lateral areas of the femur, and lateral posterior area of the femur were (44.47 ± 2.35) ms, (46.52 ± 3.12) ms, (45.47 ± 2.40) ms, (43.68 ± 2.12) ms, (46.33 ± 3.36) ms, (43.92 ± 3.42) ms, (43.58 ± 2.40) ms, (45.53 ± 3.91) ms, (44.36 ± 3.15) ms, (46.41 ± 3.04) ms, respectively in the control group. They were (49.56 ± 2.05) ms, (51.67 ± 2.38) ms, (50.47 ± 2.53) ms, (48.68 ± 3.05) ms, (51.33 ± 4.62) ms, (48.92 ± 2.53) ms, (48.58 ± 3.15) ms, (50.53 ± 3.72) ms, (48.36 ± 2.41) ms, and (51.41 ± 3.64) ms, respectively in the mild KOA group, and (53.47 ± 2.46) ms, (56.52 ± 3.57) ms, (54.85 ± 2.89) ms, (52.68 ± 3.57) ms, (56.33 ± 3.91) ms, (52.92 ± 3.04) ms, (53.58 ± 3.36) ms, (55.53 ± 3.42) ms, (52.36 ± 4.13) ms, and (56.41 ± 3.56) ms, respectively in the severe KOA group. There were significant differences in abovementioned indices among the three groups ( F = 38.768, 39.412, 38.981, 40.432, 38.416, 38.635, 38.347, 40.712, 38.158, 39.418, all P < 0.05). Conclusion:The T2 value of knee cartilage in patients with KOA is unrelated to gender and related to the severity of the disease. Magnetic resonance T2 mapping can help diagnose KOA, and provide information about the changes in cartilage components of patients with early KOA.

Structure‒tissue exposure/selectivity relationship (STR) correlates with clinical efficacy/safety

Drug optimization, which improves drug potency/specificity by structure‒activity relationship (SAR) and drug-like properties, is rigorously performed to select drug candidates for clinical trials. However, the current drug optimization may overlook the structure‒tissue exposure/selectivity-relationship (STR) in disease-targeted tissues vs. normal tissues, which may mislead the drug candidate selection and impact the balance of clinical efficacy/toxicity. In this study, we investigated the STR in correlation with observed clinical efficacy/toxicity using seven selective estrogen receptor modulators (SERMs) that have similar structures, same molecular target, and similar/different pharmacokinetics. The results showed that drug's plasma exposure was not correlated with drug's exposures in the target tissues (tumor, fat pad, bone, uterus), while tissue exposure/selectivity of SERMs was correlated with clinical efficacy/safety. Slight structure modifications of four SERMs did not change drug's plasma exposure but altered drug's tissue exposure/selectivity. Seven SERMs with high protein binding showed higher accumulation in tumors compared to surrounding normal tissues, which is likely due to tumor EPR effect of protein-bound drugs. These suggest that STR alters drug's tissue exposure/selectivity in disease-targeted tissues vs. normal tissues impacting clinical efficacy/toxicity. Drug optimization needs to balance the SAR and STR in selecting drug candidate for clinical trial to improve success of clinical drug development.

Structure-based discovery of orally efficient inhibitors via unique interactions with H-pocket of PDE8 for the treatment of vascular dementia

Our previous study demonstrated that phosphodiesterase 8 (PDE8) could work as a potential target for vascular dementia (VaD) using a chemical probe 3a. However, compound 3a is a chiral compound which was obtained by chiral resolution on HPLC, restricting its usage in clinic. Herein, a series of non-chiral 9-benzyl-2-chloro-adenine derivatives were discovered as novel PDE8 inhibitors. Lead 15 exhibited potent inhibitory activity against PDE8A (IC50 = 11 nmol/L), high selectivity over other PDEs, and remarkable drug-like properties (worthy to mention is that its bioavailability was up to 100%). Oral administration of 15 significantly improved the cAMP level of the right brain and exhibited dose-dependent effects on cognitive improvement in a VaD mouse model. Notably, the X-ray crystal structure of the PDE8A-15 complex showed that the potent affinity and high selectivity of 15 might come from the distinctive interactions with H-pocket including T-shaped π-π interactions with Phe785 as well as a unique H-bond network, which have never been observed in other PDE-inhibitor complex before, providing new strategies for the further rational design of novel selective inhibitors against PDE8.

Target-based anticancer indole derivatives and insight into structure‒activity relationship: A mechanistic review update (2018-2021)

Cancer, which is the uncontrolled growth of cells, is the second leading cause of death after heart disease. Targeting drugs, especially to specific genes and proteins involved in growth and survival of cancer cells, is the prime need of research world-wide. Indole moiety, which is a combination of aromatic-heterocyclic compounds, is a constructive scaffold for the development of novel leads. Owing to its bioavailability, high unique chemical properties and significant pharmacological behaviours, indole is considered as the most inquisitive scaffold for anticancer drug research. This is illustrated by the fact that the U.S. Food and Drug Administration (FDA) has recently approved several indole-based anticancer agents such as panobinostat, alectinib, sunitinib, osimertinib, anlotinib and nintedanib for clinical use. Furthermore, hundreds of studies on the synthesis and activity of the indole ring have been published in the last three years. Taking into account the facts stated above, we have presented the most recent advances in medicinal chemistry of indole derivatives, encompassing hot articles published between 2018 and 2021 in anticancer drug research. The recent advances made towards the synthesis of promising indole-based anticancer compounds that may act via various targets such as topoisomerase, tubulin, apoptosis, aromatase, kinases, etc., have been discussed. This review also summarizes some of the recent efficient green chemical synthesis for indole rings using various catalysts for the period during 2018-2021. The review also covers the synthesis, structure‒activity relationship, and mechanism by which these leads have demonstrated improved and promising anticancer activity. Indole molecules under clinical and preclinical stages are classified into groups based on their cancer targets and presented in tabular form, along with their mechanism of action. The goal of this review article is to point the way for medicinal chemists to design and develop effective indole-based anticancer agents.

Advances in the study of structural modification and biological activities of asiatic acid / 药学学报

Asiatic acid (AA) is a ursane pentacyclic triterpenoids, which possesses a wide range of pharmacological activities, such as anti-tumor, hypoglycemic, anti-inflammatory, anti-bacterial. Due to poor solubility and low bioavailability, clinical application of asiatic acid is limited. To address these defects, the structural modifications of AA have been carried out, and large numbers of AA-based derivatives with novel structure and eximious biological activity have been developed. In this paper, the research progress of structural modifications, biological activity, structure-activity relationship and mechanism studies in recent twenty years are reviewed, which provides reference for development of AA-related drugs.

Advanced structure analysis and structure-activity relationship of polysaccharide SGP-2 from Sarcandra glabra / 中国药科大学学报

@#SGP-2 was an acidic polysaccharide with good hypoglycemic activity isolated from Sarcandra glabra (Thunb.) Nakai in the previous study. This study used the laser particle size analysis, transmission electron microscopy (TEM) and atomic force microscopy(AFM) analysis techniques to analyze the advanced structure of SGP-2 in the deionized water and Na2SO4 solution and discuss the structure-activity relationship between the advanced structural characterizations and the α-glucosidase inhibition activities of SGP-2 and its derivative in vitro.Results showed that SGP-2 presented aggregates and spheres in the deionized water.AFM analysis showed that the diameter of SGP-2 was 33 nm and the height was 1.84 nm, whereas compact spherical conformations with high degrees of branching were observed in 0.05 mol/L Na2SO4 solution and SGP-2 had smaller particle size in saline solution compared with that in water.SGP-2 treated by 0.5 mol/L urea and dialysis at the concentration of 1 000 μg/mL showed 98.8% inhibition activity of that from untreated SGP-2. The inhibition rate of short rod conformation with branches reached 83.3% when the temperature rose up to 140 °C, and the α-glucosidase inhibition activity was even higher than that of untreated SGP-2 under the same condition; while SGP-2 with the tangled glycan chains under the condition of carboxyl group reduced had much lower inhibition activity.Therefore, the spherical structure or the short rod conformation with branches played an important role in the activity of SGP-2. This research provides a theoretical basis for further study of structure-function relationship between the advanced structure and activity of polysaccharides.

Synthesis，anti-melanoma activity and acute toxicity of aporphine alkaloids in zebrafish / 中国药科大学学报

@#In this study, 10 aporphine alkaloids were synthesized with 1, 2-methylenedioxy substituent in ring A and 9, 10, 11-position with different substituents in ring D. Their structures were determined by ESI-MS,13C NMR and 1 H NMR.The potencial antitumor activity of these compounds against B16F10 melanoma cells were evaluated by MTT assay, and their structure-activity relationship was further analyzed.Meanwhile, zebrafish acute toxicity test was conducted to evaluate the safety of the active compounds.The results showed that some compounds had strong inhibitory activity on tumor cells, and could significantly inhibit the proliferation of B16F10 melanoma cells.Compound IVa has the best anti-melanoma activity with wide safety range, and can be used as a lead compound for further study on anti-proliferation of B16F10 melanoma cells.

Discovery of 4-arylthiophene-3-carboxylic acid as inhibitor of ANO1 and its effect as analgesic agent

Anoctamin 1 (ANO1) is a kind of calcium-activated chloride channel involved in nerve depolarization. ANO1 inhibitors display significant analgesic activity by the local peripheral and intrathecal administration. In this study, several thiophenecarboxylic acid and benzoic acid derivatives were identified as novel ANO1 inhibitors through the shape-based virtual screening, among which the 4-arylthiophene-3-carboxylic acid analogues with the best ANO1 inhibitory activity were designed, synthesized and compound

Research progress on naturally-occurring and semi-synthetic ocotillol-type ginsenosides in the genus Panax L. (Araliaceae) / 中国天然药物

Ocotillol (OT)-type ginsenosides, one subtype of ginsenosides, consist of a dammarane skeleton and a tetrahydrofuran ring. Most naturally-occurring OT-type ginsenosides exist in Panax species, particularly in Panax quinquefolius, which may be attributed to the warm and humid climate of its native areas. Till now, merely 28 types of naturally-occurring OT-type ginsenosides have been isolated. In contrast, semi-synthesized OT-type ginsenosides are attracted considerable attentions. These ginsenosides can be obtained through oxidation and cyclization of side chains of dammarane-type ginsenosides, and other methods, which may change their physical and chemical properties and further improve their bioavailabilities. It is also notable that the pharmacological activities of ginsenosides are closely related to the stereoisomers caused by the configuration at C-20. Semi-synthesis of OT-type ginsenosides can facilitate our understanding of the biosynthesis, transformation and metabolism of OT-type ginsenosides in the body. This review will systematically summarize the research progress on naturally-occurring and semi-synthetic OT-type ginsenosides, which provides a theoretical basis for their bioactivity-guided research.

Research progress of febuxostat derivatives as xanthine oxidase inhibitors / 药学学报

Febuxostat, as a xanthine oxidase inhibitor, is a classic anti-gout drug with significant therapeutic effects and good tolerability. The structures of febuxostat and its derivatives can be divided into two parts: a substituted phenyl ring and a five-membered or six-membered heterocyclic ring with a carboxyl substitution. This paper reviewed the research progress of febuxostat derivatives in recent ten years and classified the structure-activity relationships of various febuxostat derivatives. Exploring the action mechanisms and structure-activity relationships of xanthine oxidase inhibitors might be significant for the rational design and development of new anti-gout chemical entities.

Identification of small molecule sirtuin-1 inhibitors for treating acute myeloid leukemia based on molecular docking, quantitative structure-activity relationships and molecular dynamics / 药学学报

The purpose of this study was to discover novel inhibitors of sirtuin-1 (SIRT1) that could be used in the treatment of acute myeloid leukemia (AML). Eight potential SIRT1 inhibitors were identified from 231 511 natural drug-like molecules by virtual screening-based molecular docking and molecular mechanics-generalized Born surface area (MM-GBSA) calculation of binding free energies. Using existing SIRT1 inhibitor molecules as training and test sets, a series of quantitative structure-activity relationship models were established, and the best quantitative structure-activity relationship (QSAR) model was used to predict the IC50 of these 8 potential inhibitor molecules for SIRT1. Subsequently, molecular dynamics simulations were performed to verify the binding mode and stability of these complexes of potential inhibitors and SIRT1 protein. Finally, the activity of these potential SIRT1 inhibitors was verified by cell proliferation assays of OCI-AML2, OCI-AML3 and MV4-11 cells and SIRT1 enzyme activity assays, and it was found that 5 compounds could inhibit AML cell proliferation. Among them, the most active compound, ZINC000001774455, had an IC50 of 2.29 ± 0.09 μmol·L-1 with OCI-AML2 cells, and at a concentration of 1 μmol·L-1, the inhibitory ratio of this compound on SIRT1 protein activity was 65.33%. ZINC000001774455 can be used as a lead compound for the development of new AML treatments.