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The acceptor substrate specificity of dextransucrase from Streptococcus sanguis 10558 was examined utilizing analogs of methyl-α- d -glucopyranoside. The analogs include a series of α-methyl glycosides of several epimers, derivatives blocked at position 6, 6 blocked epimers, several β-methyl derivatives, and L-sugars. The products formed during reactions between the analogs, the enzyme and radiolabeled sucrose were separated by paper chromatography. This analysis permitted the simultaneous evaluation of transfer as well as polymerization reaction. All analogs examined served as acceptors with varying degrees of effectiveness. From the data obtained, a rough model for interaction of the enzyme with acceptors is proposed. Structural modifications at C2 and C4 produced the most significant alteration in the ability to serve as acceptors, and also inhibited the total catalytic activity of the enzyme. The enzyme is capable of using sugars in either 4 C 1 or 1 C 4 conformations. In addition, sugars blocked at C6, the normal site of glucose addition, can serve as good acceptors and therefore probably bind to the enzyme in a different orientation. The broad spectrum of analogs that can serve as acceptor suggests that the acceptor site has some flexibility.

The use of medicinal plants has gained renewed wide popularity in Africa, Asia, and most parts of the world because of the decreasing efficacy of synthetic drugs. Thus, natural products serve as a potent source of alternative remedy. Tetrapleura tetraptera is a medicinal plant with cultural and traditional significance in West Africa. In addition to the plant being commonly used as a spice in the preparation of traditional spicy food for postpartum care it is also widely used to constitute herbal concoctions and decoctions for treatment of diseases. This review aimed to provide an up-to-date information on the ethnomedicinal uses, pharmacological activities and phytoconstituents of T. tetraptera. Preclinical studies regarding the plant's toxicity profile were also reviewed. For this updated review, literature search was done on PubMed, Science Direct, Wiley, and Google Scholar databases using the relevant keywords. The review used a total of 106 papers that met the inclusion criteria from January 1989 - February 2022 and summarised the bioactivities that have been reported for the rich phytoconstituents of T. tetraptera studied using various chemical methods. Considering the huge report, the review focused on the antimicrobial and antiinflammatory activities of the plant extracts and isolated compounds. Aridan, aridanin and several bioactive compounds of T. tetraptera have shown pharmacological activities though their mechanisms of action are yet to be fully understood. This study also highlighted the influence of plant parts and extraction solvents on its biological activities. It also presented data on the toxicological profile of the plant extracts using different models. From cultural uses to modern pharmacological research the bioactive compounds of T. tetraptera have proved effective in infectious disease management. We hope that this paper provided a robust summary of the biological activities and toxicological profile of T. tetraptera, thus calling for more research into the pharmacological and pharmacokinetic activities of natural products to help combat the growing threat of drug resistance and provide guidelines for their ethnomedicinal uses.

The protected heptapeptide derivative t -butyloxycarbonyl- l -threonyl-β-benzyl- l -aspartyl- l -asparaginyl- O -benzyl- l -tyrosyl- l -threonyl-nitro- l -arginyl- l - leucine methyl ester was prepared by stepwise chain lengthening. The protecting groups on the side chains of arginine, tyrosine, and aspartic acid residues were removed by hydrogenolysis and the partially deprotected heptapeptide ester converted to the hydrazide, an intermediate in the synthesis of the (porcine) vasoactive intestinal peptide (VIP). After the removal of the tert -butyloxycarbonyl group, the heptapeptide ester was exposed to the action of trypsin which split off its C-terminal residue, l -leucine methyl ester. The hexapeptide was then exposed to chymotrypsin, which cleaved it into an acidic, and a basic fragment. The former was, under the conditions used, indistinguishable on paper chromatography and paper electrophoresis from the tetrapeptide threonyl-aspartyl-asparaginyl-tyrosine which had previously been isolated from natural VIP, of which it comprises the sequence 7–10. Similarly, the basic fragment was indistinguishable from threonyl-arginine, the sequence 11–12 of VIP. This intestinal peptide increases visceral blood flow and reduces blood pressure in the dog, and also causes relaxation of different smooth muscle preparations, e.g., the trachea of guinea pigs. The principal aim of the present synthesis is to provide independent evidence for the sequence of (porcine) VIP.

In order to study the influence of amino group on antioxidant activity of oligosaccharides, an amino disaccharide, 6,6'-diamino-6,6'-dideoxytrehalose (DAMDT) was successfully prepared in this paper, and its antioxidant activities against DPPH, superoxide, hydrogen peroxide, and hydroxyl radicals, and reducing power were evaluated, respectively. The results indicated that DAMDT had better antioxidant activity than trehalose at any tested concentration. The influence of amino group on antioxidant activity of disaccharides is positive based on the results in this paper, and amination should be an effective method to improve the bioactivity of saccharides.

Modulating inflammatory responses after stroke can prevent brain injury and, therefore, improve neurological outcome. Stephania japonica (Thunb.) Miers is a Chinese folk medicine with the function of dispelling the "wind and blockage" in the human body according to the Chinese medicine theory, in which the symptoms of stroke are caused by the "wind and blockage" in the body. In this paper, we for the first time linked S. japonica to stroke by clarifying fifteen alkaloidal constituents including five undescribed (1-5) ones and screening out six hasubanan type alkaloids (1-4, 7, 15) that elicited stronger anti-neuroinflammatory activities than the positive drug. Moreover, the total alkaloid fraction (ASJ) with previously undescribed 3 as the main component was subject to the in vivo evaluation of the protective effect in the MCAO-induced brain injury. The results showed that ASJ exhibited potent protective effect against brain injury in the MCAO rat model. The results reported in this paper suggested that the hasubanan alkaloids from S. japonica would be an important molecular source for discovering novel therapeutic agents for neuroinflammation-related diseases, such as stroke diseases.

In this paper, the synthesis, characterization and the leishmanicidal assessments of novel 8-(4-alkylpiperazinyl) caffeine derivatives have been described. These compounds are new caffeine hybrid molecules that are structurally composed of three compartments comprising caffeinyl, piperazinyl and N-alkyl/aryl residues. The synthesis was carried out through the bromination of caffeine via NBS to attain the 8-bromocaffeine (8-BC) followed by the S

Cysteine (Cys) and homocysteine (Hcy) are involved in maintaining homeostasis in the body and are relevant to various diseases. While the level of Cys and Hcy is much lower than GSH in the living system, which leads to a major challenge to selectively identify Cys/Hcy in the presence of large amounts of GSH. In this paper, an AIE fluorescent probe SQM-NBD was obtained by connecting NBD to the hydroxyl group of the fluorophore SQM-OH for selective detection of Cys/Hcy. Probe SQM-NBD had no fluorescence itself. But, under the disturbance of GSH, the fluorescence signal of probe SQM-NBD could be turned on by Cys/Hcy. The study of the response mechanism showed that probe SQM-NBD could release both SQM-OH and Cys/Hcy-NBD after reacting with Cys/Hcy. While Cys/Hcy continued to quench the fluorescence of SQM-OH through the combination of Michael addition and the ion rich environment, resulting in only the fluorescence signal of Cys/Hcy-NBD being observed. SQM-NBD appeared superior sensitivity to Cys/Hcy, with LOD of 54 nM and 72 nM, respectively. Significantly, probe SQM-NBD realized the application of fluorescence imaging of Cys/Hcy in HeLa cells, indicating that probe SQM-NBD has the potential for Cys/Hcy identification under physiological and pathological conditions.

The privileged structure binds to multiple receptors with high affinity, which is helpful to the development of new bioactive compounds. Indole is classified as a privileged structure, which may be one of the most important structural categories in drug discovery. As a special subset of indole compounds, 2-phenylindole seems to be one of most promising forerunners of drug development. In this paper, 106 articles were referenced to review the structural changes, biological activities and structure-activity relationship of compounds in recent 20 years, and classified them according to their pharmacological activities, from several aspects, including anticancer, antibacterial, anti-inflammatory, analgesic, antiviral, anti-parasite, the biological activities target to central nervous system, et al. It also points out the importance of artificial intelligence (AI) technology in discovery of new 2-phenylindole compounds in a broader prospect. This review will provide some ideas for researchers to develop new indole drugs.

Bardoxolone methyl (CDDO-Me) has exhibited positive therapeutic effects in clinical trials for diabetic nephropathy (DN), but serious safety risks in the heart exist because of the potential off-target response resulting from the highly active part of CDDO-Me. Herein, we reported a novel strategy to prepare Cathepsin B (CTSB) cleavable and improved water-soluble prodrugs of CDDO-Me. CTSB linkers connection to the highly active α-cyano-α, β-unsaturated ketone (CUK) part of CDDO-Me with the incorporation of polyethylene glycol (PEG) moieties, provided a series of prodrugs of CDDO-Me without CUK part exposure. Theoretically, these prodrugs shielding CUK part can be stably circulated and finally cleaved by CTSB in lysosomes to release CDDO-Me. In this paper, preliminary curative effects and safety of all prodrugs were determined. Wherein, prodrug 20 displayed relatively better activities than other prodrugs in inhibiting the release of NO from RAW264.7 cells, activating Keap1-Nrf2-ARE signaling pathway and inhibiting NF-κB signaling pathway, which were comparable to CDDO-Me. More importantly, prodrug 20 showed relatively lower human ether-a-go-go-related gene (hERG) inhibitory activity compared with CDDO-Me, which demonstrated prodrug 20 might be safer than CDDO-Me. In conclusion, the novel strategy of shielding CUK part with CTSB linkers provided a new idea for solving the limitations of CDDO-Me in clinical application.

Antibody-drug conjugates are gradually revolutionizing anticancer therapy. Payload is one of the most crucial components of ADC for high antitumor activity. However, there is no direct and real-time monitoring method for the intracellular release mechanism of the payload. Herein, we developed a theranostic payload that possessed dual functions of therapy and imaging. This payload consisted of the classic payload MMAE and the novel nitro-coumarin probe reported for the first time, which has the dual characteristics of electron transfer ability and the on-off fluorescence property. In this paper, the theranostic property of the novel payload has been preliminarily demonstrated. The fluorescence intensity of the payload in target cells greatly increased approximately 9 times in 120 min through the high content analysis, and the intracellular distribution of the payload could be directly monitored by a confocal microscope. In in vitro cytotoxicity assays, the payload showed broad-spectrum and high antitumor activity (0.09 nM to 1.2 nM), which was equivalent to the MMAE (0.06 nM to 1.1 nM). Moreover, the ADC loaded with L-233 maintained the theranositc property. In conclusion, our work developed a theranostic payload for the first time and provides a new direct and real-time monitoring method for intracellular studies of ADC payloads.

In this paper, we present a new donor-π bridge-acceptor type fluorescent probe, MIB, which bears two organelle-targeted groups, namely positively charged benzothiazole group for mitochondria and morpholine moiety for lysosomes. In aqueous solution, the nucleophilic addition of HSOsub3/subsup-/sup(as SOsub2/subdonor) to MIB blocked its long-range π-conjugation and ICT process and resulted in significant optical signal changes (blue-shifted UV absorbance and fluorescence), which enabled colorimetric and ratiometric fluorescent detection of HSOsub3/subsup-/supwith high selectivity and sensitivity (detection limit of 63.15 nM). MIB offers obvious advantages of good water-solubility, fast response time (within 1 min), unique dual lysosome/mitochondria targeting capability and has been applied to the sensing of endogenous and exogenous SOsub2/subin live cells through fluorescent imagingsub./subIn addition, the proposed probe has been utilized for the determination of bisulfite in real water, food and herbal medicine samples, showing good recovery (91.45 % - 109.3 %) and precision.

Asperphenamate is a natural product that has attracted considerable interest from researchers worldwide. In the last decade, aiming to increase the biological activity and improve druggability, modifications of the A-ring moiety in asperphenamate have been performed. Our laboratory has also recently reported functional derivatizations of the A ring and studied its effect on the inhibition of cysteine cathepsin L. However, the functional significance of the B-ring fragment toward cathepsin L has not been evaluated thus far. In this paper, forty-four derivatives of the B-ring substituted with different N-phenylsulfonyl groups were designed and synthesized. Among them, the paratrifluromethyl analog B-2a and the 2, 4-difluoro-5-chloro derivative B-11b showed more potent inhibitory activity against cathepsin L than the control compound, ABR, which displayed the strongest inhibitory effect on cathepsin L and S among all reported asperphenamate derivatives. In particular, compound B-2a showed more pronounced selectivity against cathepsin L than the other derivatives. Molecular docking revealed that the N-phenylsulfonylamide moiety was vital for the interactions between B-2a and cathepsin L. Moreover, B-2a displayed no toxicity against normal cells. Therefore, compound B-2a was selected for further studies. Wound-healing assays, Transwell chamber assays and breast cancer lung metastasis mouse models demonstrated that B-2a exhibited antimetastatic ability in vitro and in vivo.

In this paper, two series of novel multifunctional 1, 4-di (aryl/heteroaryl) substituted piperazine derivatives (6a-d7a-d) were synthesized, characterized, and evaluated for their antitubercular, antibacterial, and antifungal activities. A step-wise reduction, bromination and substitution reactions on various aldehydes resulted in alcohols (2a-d), bromides (3a-d), and titled novel compounds (6a-d7a-d) in moderate to good yields (48-85%). The novel compounds were evaluated for their antitubercular and antimicrobial activities. Compound 7a exhibited promising antitubercular activity (MIC: 0.65 µg/mL) almost equal to the Rifampicin, while the rest of the compounds were moderately active against MTB H37Rv except 6b. Compounds 7a and 6b showed good activity against tested fungal pathogens. Compounds 7a and 7b were proven as the best bacterial agents. Molecular docking studies were in agreement with the in-vitro results. Docking analyses show that all the synthesized molecules bind to the target protein Mtb RNAP (PDB ID: 5UHC) fairly strongly. All the compounds were evaluated for their in vitro cytotoxicity effect using the MTT assay method against human cancer cell line MCF-7. The compounds demonstrated growth inhibitory effect on the cell line with significant IC

Streblus asper Lour. (Moraceae) is a medicinal plant in Asian countries including India and Thailand, possessing activities of anti-tumor, anti-allergy, anti-parasitic and anti-bacterial. In this paper, characterization, quantitation and similarity evaluation of cardiac glycosides in different parts of S. asper were investigated by HPLC-Q-TOF-MS and chemometric methods. Then, the inhibition of Na+,K+-ATPase activity by the compounds isolated from S. asper was measured. Meanwhile, enzyme kinetics and molecular docking were determined to exhibit the combination modes between cardiac glycosides and Na+,K+-ATPase. As a result, twenty peaks of cardiac glycosides were assigned. Strophanthidin-3-O-α- l -rhamnopyranosyl-(1 → 4)-6-deoxy-β- d -allopyranoside (1), glucostrebloside (2), strebloside (4) and mansonin (8) with a significant activity of inhibiting Na+,K+-ATPase (IC50 7.55–13.60 μM) were chosen for the determination of enzyme kinetics, exhibiting anticompetitive inhibitory characteristics towards Na+,K+-ATPase. Compound 4 could reasonably bind to the active sites of Na+,K+-ATPase, proved by molecular docking. Furthermore, the contents of the major compounds in four different parts of S. asper were extremely different, analyzed by chemometric methods, similarity analysis and principle compounds analysis. All these findings indicated that the contents of major compounds in different parts of S. asper were extremely different with a significant activity of inhibiting Na+,K+-ATPase, providing a reference for determination of effective part and administered dosage. The combination modes between cardiac glycosides and Na+,K+-ATPase were also revealed by enzyme kinetics and molecular docking, which provided a basis for further study of pharmacological activity.

Betulin derivatives exhibit an antiproliferative activity and have been tested for many cancer cell lines. This paper describes a new series of 3-phosphate derivatives of betulin bearing different substituents at C28 position. The synthesized compounds were tested in vitro for their antiproliferative effect against human leukemia (MV-4-11 and CCRF/CEM), lung carcinoma (A549), prostate cancer (DU 145), melanoma (Hs 294T) cell lines, and murine leukemia P388. To explore the possible mechanism of anticancer activity for the most in vitro active compounds (4, 5, 7 and 8) and betulin, molecular docking was performed to the binding sites of potential anticancer targets, described for the various triterpene derivatives, including topoisomerase I and II, epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGFR), transcription factor NF-κB, anti-apoptotic protein Bcl-2 and peroxisome proliferator-activated receptor (PPARγ). According to the results of the docking, the best fit to the binding pocket of PPARγ was shown by compound 4.

β-Secretase (BACE1) has been broadly documented as one of the possible therapeutic targets for the treatment of Alzheimer's disease. In this paper, we report the synthesis and the for β-secretase (BACE-1) inhibitory activity of new series of tetrahydrobenzo [b] pyran derivatives. One-pot synthesis of tetrahydrobenzo [b] pyrans was carried out by condensing aromatic aldehyde, malononitrile and 1,3-cyclohexanedione using ionic liquid 1-butyl-3-methyl imidazolium chloride ([bmIm]Cl-) in aqueous alcohol media. The addition of alcohol and water in the ratio of 1:2 keeps all the reactants in solution which facilitates the reaction and makes the product formation very easy. The synthesized compounds were subjected to BACE1 inhibition assay and six compounds, 4d, 4e, 4f, 4h, 4i, and 4p have shown significant IC50 values at micromolar level. Among these six active compounds, 4e was a potential inhibitor with its IC50 value in nanomolar range. All the synthesized compounds were docked onto the active site of β-Secretase enzyme.

Agonism of S1P1 receptor has been proven to be responsible for peripheral blood lymphopenia and elicts the identification of various S1P1 modulators. In this paper we described a series of oxadiazole-based S1P1 direct-acting agonists disubstituted on terminal benzene ring, with high potency for S1P1 receptor and favorable selectivity against S1P3 receptor. In addition, two representative agents named 16-3b and 16-3g demonstrated impressive efficacy in lymphocyte reduction along with reduced effect on heart rate when orally administered. Furthermore, these compounds have been shown to possess desired pharmacokinetic (PK) and physicochemical profiles. The binding mode between 16-3b and the activated S1P1 model was also studied.

Twenty-one new iridoids, jatamansidoids A-U (1-12, 21-26, 32, 35 and 36), two new natural ones, jatamansidoids V (37) and W (38), eighteen known ones (13-20, 27-31, 33 and 34), together with three patchoulol-type sesquiterpenoids (39-41), were isolated from the roots and rhizomes of Valeriana jatamansi. Structurally, compounds 1-7 were the first examples of iridoids from V. jatamansi with unique α, β, γ, δ-unsaturated aldehyde fragment between C-11, C-4, C-5, C-9 and C-8; compound 8 was an unprecedented iridoid derivative with a methyl group (Me-10) at C-1, rather than C-8, and its plausible biogenetic pathway was proposed in this paper; compounds 22 and 23 were the first examples of Δ

Tuberculosis is an infectious disease that affects millions of population every year. Mtb-DHFR is a validated target that is vital for nucleic acids biosynthesis and therefore DNA formation and cell replication. This paper report identification and synthesis of novel compounds for selective inhibition of Mtb-DHFR and unleash the selective structural features necessary to inhibit the same. Virtual screening of databases was carried out to identify novel compounds on the basis of difference between the binding pockets of the two proteins. Consensus docking was performed to improve upon the results and best ten hits were selected. Hit 1 was subjected to analogues design and the analogues were docked against Mtb-DHFR. From the docking results 11 compounds were selected for synthesis and biological assay against H37Rv. Most potent compound (IND-07) was tested for selectivity using enzymatic assay against Mtb-DHFR and h-DHFR. The compounds were found to have good inhibitory activity (25-200 µM) against H37Rv and in enzyme assay against Mtb-DHFR and h-DHFR the compound was found selective towards Mtb-DHFR with selectivity index of 6.53. This work helped to identify indole moiety as novel scaffold for development of novel selective Mtb-DHFR inhibitors as antimycobacterial agents.

Bile acids, initially discovered as endogenous ligands of farnesoid X receptor (FXR), play a central role in the regulation of triglyceride and cholesterol metabolism and have recently emerged as a privileged structure for interacting with nuclear receptors relevant to a large array of metabolic processes. In this paper, phenoxy containing cholic acid derivatives with excellent drug-likeness have been designed, synthesized, and assayed as agents against cholesterol accumulation in Raw264.7 macrophages. The most active compound 14b reduced total cholesterol accumulation in Raw264.7 cells up to 30.5% at non-toxic 10 μM and dosage-dependently attenuated oxLDL-induced foam cell formation. Western blotting and qPCR results demonstrate that 14b reduced both cholesterol and lipid in Raw264.7 cells through (1) increasing the expression of cholesterol transporters ABCA1 and ABCG1, (2) accelerating ApoA1-mediated cholesterol efflux. Through a cell-based luciferase reporter assay and molecular docking analysis, LXR was identified as the potential target for 14b. Interestingly, unlike conventional LXR agonist, 14b did not increase lipogenesis gene SREBP-1c expression. Overall, these diverse properties disclosed herein highlight the potential of 14b as a promising lead for further development of multifunctional agents in the therapy of cardiovascular disease.

The fruit of Citrus medica L. var. sarcodactylis Swingle is a functional food with rich nutrients and medicinal values because of its content of bioactive compounds. A bioactivity-guided chemical investigation from the fruits of C. medica L. var. sarcodactylis Swingle afforded three new benzodioxane neolignans (1–3), three new phenanthrofuran neolignan glycosides (4–6), two new biphenyl-ketone neolignans (7–8), two new 1′,7′-bilignan neolignans (9–10), as well as fourteen known neolignan derivatives (11–24), which were isolated and characterized from the fruits of C. medica L. var. sarcodactylis Swingle for the first time. These neolignan derivatives were determined by extensive and comprehensive analyzing NMR, HR-ESI-MS, UV, IR spectral data and compared with the data described in the literature. Among them, compounds 1–3 and 12–13 exhibited moderate hepatoprotective activities to improve the survival rates of HepG2 cells from 46.26 ± 1.90% (APAP, 10 mM) to 67.23 ± 4.25%, 62.87 ± 4.43%, 60.06 ± 6.34%, 56.75 ± 2.30%, 58.35 ± 6.14%, respectively. Additionally, compounds 7–8 and 21–22 displayed moderate neuroprotective activities to raise the survival rates of PC12 cells from 55.30 ± 2.25% to 66.94 ± 3.37%, 70.98 ± 5.05%, 64.64 ± 1.93%, and 62.81 ± 4.11% at 10 μM, respectively. The plausible biogenetic pathway and preliminary structure–activity relationship of the selected compounds were scientifically summarized and discussed in this paper.

This paper presents the design and synthesis of 4-(3-hydroxyanilino)-6-(1H-1,2,3-triazol-4-yl)quinazolines of scaffold 9 as selective B-Raf/B-Raf

The selective inhibition of inducible nitric oxide synthase (iNOS) has become an interesting goal for the treatment of diseases where the immune and inflammatory response of the organism is involved. Septic shock is one prominent example of this type of affections. In this paper, the design and synthesis of twelve substituted pyridinyl- imidamide derivatives is described, together with their biological evaluation as NOS inhibitors. The most potent and selective compound was N-(3-hydroxy-3-(pyridin-3-yl)propyl)acetimidamide 9a (IC50 = 4.6 µM, against iNOS). Pharmacological assays in aortic rat tissue, have confirmed its inhibitory activity on iNOS and the absence of undesired cardicovascular effects. In silico analysis of the most promising compounds (9a, 9b, 9e and 9g) have predicted good drug-likeness properties. Furthermore, they have shown an adequate cell viability. Docking studies carried out on 9a suggest a particular binding mode that involves the essential residue Glu377, and might explain its iNOS selectivity. From a chemical point of view, the article describes an unusual cyclization to obtain pyridinyl-pyrimidine derivatives with high yield., Centro de Supercomputación de la Universidad de Granada (CSIRC), Ministerio de Economia y Competitividad, Instituto de Salud Carlos III (CIBER-CV) y Ministerio de Economía y competitividad (MINECO) (SAF2017-84894-R y PID2020-116347RB-100), Biblioteca de la Universidad de Granada

The enzymatic family of heme oxygenase (HO) is accountable for heme breakdown. Among the two isoforms characterized to date, HO-2 is poorly investigated due to the lack of potent HO-2 chemical modulators and the greater attentiveness towards HO-1 isoform. In the present paper, we report the rational design and synthesis of HO-2 inhibitors achieved by modulating the volume of known HO-1 inhibitors. The inhibition preference has been moved from HO-1 to HO-2 by merely increasing the volume of the substituent in the western region of the inhibitors. Docking studies demonstrated that new derivatives soak differently in the two binding pockets, probably due to the presence of a Tyr187 residue in HO-2. These findings could be useful for the design of new selective HO-2 compounds.

With the increasing risk of invasive and life threating fungal infections, there is now a great concern regarding the lower discovery rate of antifungal drugs in comparison to antimicrobial agents. Drugs conventionally used in clinics are not adequate enough to combat the increasing fungal infections, especially fungal forms resistant to fluconazole. Among the limited antifungal agents in clinics, azoles have the largest number of drug candidates in clinical trials and are partly marketed due to the particular focus of pharmaceutical companies and medicinal scientific centers. With the rise in the number of papers on azole antifungal design and discovery, a more in-depth understanding the most recent and authentic information about this class of drugs might be beneficial. To this end, we for the first time summarized the state-of-the-art information about azole drugs, with a specific focus on those in the pipelines of pharmaceutical companies, into four generations with regard to their structural similarity. More importantly, this review highlights information on the structure activity relationship (SAR), target description, hybrid antifungal agents as possible future generation, and other useful issues to streamline research towards designing new efficient azole antifungal structures in future.

β-ionone, a cyclic terpenoid compound present in many fruits, has been showed a broad spectrum of biological activities. In this paper, we synthesized a panel of β-ionone derivatives and tested their anti-proliferation activity on cancer cell by the MTT assay. The results showed that most of the β-ionone derivatives were more active than β-ionone and curcumin. Particularly, the β-ionone derivatives (1a, 1d and 1g) with ortho-substituents on the aromatic ring exhibited much stronger cytotoxicity than their corresponding meta- and para-substituted compounds. Importantly, the cytotoxicity of the β-ionone derivatives (1a, 1d and 1g) were relationship with their reactive oxygen species (ROS)-generation abilities, which could lead to the redox imbalance, lipid peroxidation, the loss of mitochondrial membrane potential (MMP), the activation of Bax and Caspase 3, followed by cell apoptosis. This work suggest that the “ortho effect”, the ROS-generation ability and drawing fluorine atom into drugs may play a potent role in enhancing the anticancer activity of β-ionone derivatives.

Alkaline phosphatases (APs) are a class of homodimeric enzymes which physiologically possess the dephosphorylation ability. APs catalyzes the hydrolysis of monoesters into phosphoric acid which in turn catalyze a transphosphorylation reaction. Thiazoles are nitrogen and sulfur containing aromatic heterocycles considered as effective APs inhibitors. In this context, the current research paper presents the successful synthesis, spectroscopic characterization and in vitro alkaline phosphatase inhibitory potential of new thiazole derivatives. The structure activity relationship and molecular docking studies were performed to find out the binding modes of the screened compounds with the target site of tissue non-specific alkaline phosphatase (h-TNAP) as well as intestinal alkaline phosphatase (h-IAP). Compound 5e was found to be potent inhibitor of h-TNAP with IC50 value of 0.17 ± 0.01 µM. Additionally, compounds 5a and 5i were found to be highly selective toward h-TNAP with IC50 values of 0.25 ± 0.01 µM and 0.21 ± 0.02 µM, respectively. In case of h-IAP compound 5f was the most potent inhibitor with IC50 value of 1.33 ± 0.10 µM. The most active compounds were resort to molecular docking studies on h-TNAP and h-IAP to explore the possible binding interactions of enzyme-ligand complexes. Molecular dynamic simulations were carried out to investigate the overall stability of protein in apo and holo state.

Extracellular ATP activates purinergic receptors such as P2X7, cationic channels for Ca2+, K+, and Na+. There is robust evidence of the involvement of these receptors in the immune response, so P2X7 receptors (P2X7R) are considered a potential therapeutic target for the development of anti-inflammatory drugs. Although there are many studies of the anti-inflammatory properties of naphthoquinones, these molecules have not yet been explored as P2X7 antagonists. In previous work, our group prepared 3-substituted (halogen or aryl) 2-hydroxy-1,4-naphthoquinones and studied their action on P2X7R. In this paper, eight 2-amino-3-aryl-1,4-naphthoquinones were evaluated to identify the inhibitory activity on P2X7R and the toxicological profile. Three analogues (AD-4CN, AD-4Me, and AD-4F) exhibited reduced toxicity for mammalian cells with CC50 values higher than 500 µM. These three 3-substituted 2-amino-1,4-naphthoquinones inhibited murine P2X7R (mP2X7R) in vitro. However, the analogues AD-4CN and AD-4Me showed low selectivity index values. AD-4F inhibited both mP2X7R and human P2X7R (hP2X7R) with IC50 values of 0.123 and 0.93 µM, respectively. Additionally, this analogue exhibited higher potency than BBG at inhibiting the ATP-induced release of IL-1β in vitro. Carrageenan-induced paw edema in vivo was reversed for AD-4F with an ID50 value of 11.51 ng/kg. Although AD-4F was less potent than previous 3-substituted (halogen or aryl) 2-hydroxy-1,4-naphthoquinones such as AN-04 in vitro, this 3-substituted 2-amino-1,4-naphthoquinone revealed higher potency in vivo to reduce the edematogenic response. In silico analysis suggests that the binding site of the novel 2-amino-3-aryl-1,4-naphthoquinone derivatives, including all the tautomeric forms, is located in the pore area of the hP2X7R model. Based on these results, we considered AD-4F to be a satisfactory P2X7R inhibitor. AD-4F might be used as a scaffold structure to design a novel series of inhibitors with potential inhibitory activity on murine (mP2X7R) and human (hP2X7R) P2X7 receptors.

α-Methylacyl-CoA racemase (AMACR; P504S) is a promising novel drug target for prostate and other cancers. Assaying enzyme activity is difficult due to the reversibility of the ‘racemisation’ reaction and the difficulties in the separation of epimeric products; consequently few inhibitors have been described and no structure–activity relationship study has been performed. This paper describes the first structure–activity relationship study, in which a series of 23 known and potential rational AMACR inhibitors were evaluated. AMACR was potently inhibited (IC 50 = 400–750 nM) by ibuprofenoyl-CoA and derivatives. Potency was positively correlated with inhibitor lipophilicity. AMACR was also inhibited by straight-chain and branched-chain acyl-CoA esters, with potency positively correlating with inhibitor lipophilicity. 2-Methyldecanoyl-CoAs were ca. 3-fold more potent inhibitors than decanoyl-CoA, demonstrating the importance of the 2-methyl group for effective inhibition. Elimination substrates and compounds with modified acyl-CoA cores were also investigated, and shown to be potent inhibitors. These results are the first to demonstrate structure–activity relationships of rational AMACR inhibitors and that potency can be predicted by acyl-CoA lipophilicity. The study also demonstrates the utility of the colorimetric assay for thorough inhibitor characterisation.

Alzheimer is a neurodegenerative disease and requires the development of new scaffold to treat it. In this regard, thiazoles derivative are playing their significant role. In the current research paper we have focused our attention for the development of tetrasubstituted thiazole (3a-h) derivatives using domino synthesis by mixing the thiourea as a precursor, with acetophenone in the presence of iodine and tosic acid in DMSO and refluxed for 12–22 h. The structures of the newly synthesized compounds were confirmed by FTIR, 1H NMR, 13C NMR and EIMS analysis. Thiazole derivatives were analyzed for their biological significances against acetyl and butylcholinesterase enzymes and compound 3b and 3d were found more active against these enzyme, respectively. The mode of inhibition was determined for the potent compounds against both the enzymes. Moreover, the molecular docking studies were carried out to explore the interactive behavior of the compounds within the active pocket of enzymes. Furthermore, the derivatives (3a-h) were evaluated for their anticancer potential against HeLa cancer cell lines. Most potent inhibition was observed by compound 3b.

A new series of novel nonquaternary conjugates and non-oxime reactivators for reactivation of both nerve agents and pesticides inhibited hAChE were described in this paper. Conjugates with piperazine linked to the substituted salicylaldoxime emerged as efficient reactivators for VX inhibited hAChE. The in vitro reactivation experiment showed that some of them were equal or more efficient reactivators for pesticides inhibited hAChE than obidoxime. It was also found that some non-oxime derivatives of Mannich phenols displayed obvious reactivation potency for VX, sarin and pesticides inhibited hAChE even in very low concentration. It has been proved that introduction of peripheral site ligands with widespread aromatic system and amide substitutions could increase binding affinity for inhibited hAChE in most cases, which contribute to the reactivation efficiency.

In this paper, chemical investigation on the chloroform soluble fraction of seed kernels of Caesalpinia bonduc resulted in the isolation of five new cassane diterpenoids: norcaesalpinin O (1), norcaesalpinin P (2), caesalpinin MQ (3), caesall O/P (4/5) and seven known compounds (6–12). Compounds structures were elucidated by 1H NMR, 13C NMR, 2D NMR, HR-MS and ECD (electronic circular dichroism) spectral analysis. The characters for new compounds with the presence of an aromatized C ring or demethyl group at C-17 position in the structures were found. By means of bioactive screenings, the inhibitory effect on type-4 phosphodiesterase (PDE4, the target protein of asthma disease) and nuclear factor-kappa B (NF-κB) expression were valued. Compound 1 was found to exhibit moderate inhibitory activity on PDE4 and much better binding affinity than other structures by docking studies for interaction analyzing. Compounds 6, 10 and 11 displayed considerable inhibitory strength against NF-κB expression with inhibitory ratio 48.6%, 42.9% and 37.1% at 10 µM, respectively. The isolation of cassane-type diterpenoids with anti-inflammation activity from C. bonduc implied that this plant might be a good source for anti-inflammation agents finding.

One of the most successful approaches for designing carbonic anhydrase (CA, EC 4.2.1.1) inhibitors was denominated ‘the sugar approach’. The sugar approach consists in attaching different carbohydrates to CA inhibiting pharmacophores for modulating the physicochemical properties of these pharmacological agents. In line with this approach, in this paper, we present a new class of C-glycosides incorporating the sulfamoylphenyl moiety. These compounds have been prepared by sulfamoylation of C-glycosyl phenols, which have been synthetized by aldol reaction of glycosyl ketones with the appropriate aromatic aldehydes. The inhibition profile of the new glycomimetics was determined against four human (h) CA isozymes, comprising hCAs I and II (cytosolic, ubiquitous isozymes), hCA IV and hCA IX (tumor associated isozyme). Peracetylated and deprotected C-glycosyl sulfamates showed better inhibition selectivity compared to structurally related phenylsulfamates. In this study, deprotected compound 12 was identified as selective inhibitor of hCA IX. These results confirm that attaching carbohydrate moieties to CA sulfamoylphenyl pharmacophore improves its inhibitory activity. Fil: Riafrecha, Leonardo Ezequiel. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Bua, Silvia. Università degli Studi di Firenze; Italia Fil: Supuran, Claudiu T.. Università degli Studi di Firenze; Italia Fil: Colinas, Pedro Alfonso. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Organelles possess critical biological effects in cellular processes. However, the relationship between organelle targeting and antitumour activity is a challenging issue. In this paper, a number of amide/acylhydrazine modified naphthalimide derivatives were designed and synthesized. Interestingly, amide modified naphthalimide derivatives NI-A-NH and NI-C-NH with (R)-piperdine and (S)-pyrrolidine functionalization exhibited enhanced cytotoxicity compared with acylhydrazine modified derivatives NI-A-2NH and NI-C-2NH. However, acylhydrazine modified derivatives NI-B-2NH and NI-D-2NH with (S)-piperdine and achiral piperdine conjugates possessed better cytotoxicity than NI-B-NH and NI-D-NH with amide modifications. Fluorescence imaging, DNA binding interactions and cell cycle analyses were further completed to clarify that the nucleus-targeting effects showed enhanced cytotoxic activity, strong DNA binding and the blocking of cells in S phase. These results provide a preliminary theoretical basis for the further design of organelle-targeting antitumour drugs.

In this paper, we report the inactivation of copper containing bovine plasma amine oxidase (BPAO) by a series of saturated alkylamines containing halogen atoms at γ-position, which are 1,1,1-trihalo-3-aminopropane, 1,1,1-trifluoro-2-hydroxy-3-aminopropane, 1,1,1-trichloro-2-hydroxy-3-aminopropane, and 1,1,1-trichloro-2-(2-phenethyloxy)-3-aminopropane. The trihalo-2-hydroxypropylamine analogs exhibited a time-dependent inactivation behavior of BPAO, with 1,1,1-trifluoro-2-hydroxy-3-aminopropane as the most efficient inactivator. The incorporation of a OH group at β-position increased inactivation efficiency by 10-fold within the trifluoro analogs, and the incorporation of a phenethyloxy group at β-position exhibited a higher efficiency by 3-fold within the trichloro analogs based on I75 values. All four compounds were found to be irreversible inactivators for BPAO.

The present paper explicates the synthesis of 1H-1,2,3-triazole tethered tacrine-chalcone conjugates and evaluation of their AChE and BuChE inhibitory activity. In-vitroAChE inhibition assay revealed three compounds, 9h, 9i, and 11f, being more potent than the standard drug tacrine and further evaluated against butyrylcholinesterase. The present study was extended to investigate the anti-amnestic effect of promising compoundson scopolamine-induced behavioral and neurochemical changes in mice. Inclined plane model and Elevated plus-maze model were performed to assess general limb motor activity and anxiety-like behavior, respectively, in mice pre-treated with scopolamine. Oxidative stress parameters reduced glutathione contents (GSH) and lipid peroxidation products (TBARS) in the brain homogenates as estimated using ex-vivo studies. Furthermore, molecular docking studies were performed for the potent compounds to decipher the mechanism of observed activities.

Antioxidants with high efficacy and low toxicity have the potential to treat cerebral ischemia reperfusion injury (CIRI). Dienone monocarbonyl curcumin analogs (DMCA) capable of overcoming the instability and pharmacokinetic defects of curcumin possess notable antioxidant activity but are found to be significantly toxic. In this study, a novel skeleton of the monoenone monocarbonyl curcumin analogue sAc possessing reduced toxicity and improved stability was designed on the basis of the DMCA skeleton. Moreover, 32 sAc analogs were obtained by applying a green, simple, and economical synthetic method. Multiple sAc analogs with an antioxidant protective effect in PC12 cells were screened using an H2O2-induced oxidative stress damage model, and quantitative evaluation of structure–activity relationship (QSAR) model with regression coefficient of R2 = 0.918921 was built through random forest algorithm (RF). Among these compounds, the optimally active compound sAc15 elicited a potent protective effect on cell growth of PC12 cells by effectively eliminating ROS generation in response to oxidative stress injury by activating the Nrf2/HO-1 antioxidant signaling pathway. In addition, sAc15 exhibited good protection against CIRI in the mice middle cerebral artery occlusion (MCAO) model. In this paper, we provide a novel class of antioxidants and a potential compound for stroke treatment.

P- glycoprotein (P-gp)-mediated multidrug resistance (MDR) has become an important hindrance in the clinical treatment of malignant tumors. In this paper, based on our lead compound 5m and strategies of bioisosteric replacement and alkoxy effect, phenylthiophene and phenylpyridine derivatives were designed as chemosensitizers for front-line antineoplastic agents and overcomes P-gp mediated MDR in MCF-7/ADR cell. Generally, 4-phenylthiophene-2-carboxamide derivative 60 has been screened and obtained with optimal activity against P-gp mediated MDR in MCF-7/ADR (IC50 (doxorubicin) = 1.02 μM, RF = 49.9 with 5 μM 60 treated). The results of western blot and Rh123 accumulation assays showed that 60 effectively inhibited P-gp efflux function but not its expression. It is noted that compound 60 is a potentially broad-spectrum chemosensitizer in combination with commonly used anti-tumor drugs, such as doxorubicin, paclitaxel, daunorubicin and vincristine with RF value of 20–80.

The cardiovascular side effects associated with COX-2 selective drugs were the worst for coxibs leading to their withdrawal from the market a few years after their discovery. Therefore, the design of new series of pyrazole (4a,b 5a,b, 7a,b, 9a,b, 10a-h, and 11a-f) substituted with a triazole moiety as selective COX-2 inhibitors with cardioprotective effect was aimed in this paper. The target compounds were prepared and evaluated in-vitro against COX-1 and COX-2 enzymes. Compound 5-(5-Methyl-1-phenyl-1H-pyrazol-4-yl)-4H-1,2,4-triazole-3-thiol (7a) showed the highest selectivity towards COX-2 enzyme (S.I. = 27.56) and was the most active anti-inflammatory agent. Interestingly, its cardiovascular profile showed the cardiac biomarkers (ALP, AST, CK-MB, and LDH), as well as inflammatory cytokines named (TNF-α and IL-6) nearly similar to the control. Besides, a histopathological study of the heart muscle and the stomach was also included. The results confirmed that compound 7a has a more favorable cardio profile than celecoxib. Moreover, docking simulation for the most selective compounds 4b, 7a, 10e, 11c, and 11e inside COX-2 active site was performed to explain their binding mode. Finally, an ADME study was applied and proved the promising activity of the new compounds as a new oral anti-inflammatory agent. In conclusion, the newly developed compound 7a represents a potential selective COX-2 NSAID candidate with minimum cardiovascular risks.

The current paper deals with 8-hydroxyquinoline derived p-halo N4-phenyl substituted thiosemicarbazones, their crystal structures, spectral characterization and in vitro cytotoxic studies of Co(III), Ni(II) and Cu(II) complexes. The molecular structures of the ligands, (E)-4-(4-halophenyl)-1-((8-hydroxyquinoline-2-yl)methylene)thiosemicarbazones (halo = fluoro/chloro/bromo) are determined by single crystal X-ray diffraction method. The crystal structures reveal that the ligands are non-planar and exist in their thioamide tautomeric forms. The various physicochemical investigations of the synthesized complexes reveal metal to ligand stoichiometry to be 1:2 in Co(III) complexes whereas 1:1 in Ni(II) and Cu(II) complexes. The ligands coordinate in a tridentate NNS fashion around Co(III) centers to form an octahedral geometry and square planar geometry around Ni(II) and Cu(II) metal centers. The oxidation of Co(II) to Co(III) is observed on complexation. The synthesized compounds are subjected to in vitro cytotoxicity studies. When compared to bare ligands, the complexes show enhancement of the antiproliferative activity against MCF-7, breast cancer cell lines. The Co(III) complexes of fluoro and bromo derivatives of ligands have displayed remarkable results with roughly two fold increase in their activity in correlation to the standard drug, Paclitaxel. Moreover, the fluorescence microscopy images of cells stained with acridine orange-ethidium bromide suggest an apoptotic mode of cell death.

Human caseinolytic protease proteolytic subunit (HsClpP) is a highly conserved serine protease that plays an essential role in cell homeostasis through removal of the damaged and/or misfolded proteins. Recently, due to its critical role in cancer proliferation and metastasis, HsClpP has been considered as a promising target for the cancer treatment. In this paper, through a random screening toward a library of 2086 bioactive chemicals, a novel compound I, 3-(3,5-dibromo-4-hydroxybenzylidene) -5-iodoindolin-2-one, was identified as a potent suppressor of HsClpP. Herein, a series of compound I derivatives were synthesized, and evaluated for their anti-cancer activities on a variety of cancers cells. Through the preliminary biological assay in vitro, including MTT assay and proteolytic activity assay, compound I was identified as the most potent inhibitor. Treatment with compound I impaired the migration of Hela cells. In addition, compound I disrupted the mitochondrial function, and reduced the level of the SDHB and induced the production of the ATF4. In general, compound I is a promising probe of HsClpP for cancer treatment, and is a good lead compound for the development of novel anti-cancer agent.

This paper presents the design and synthesis of 4-(3-hydroxyanilino)-6-(1H-1,2,3-triazol-4-yl)quinazolines of scaffold 9 as selective B-Raf/B-RafV600E and potent EGFR/VEGFR2 kinase inhibitors. Total 14 compounds of scaffold 9 having different side chains at the triazolyl group with/without fluoro substituents at the anilino group were synthesized and investigated. Among them, 9m with a 2-carbamoylethyl side chain and C-4′/C-6′ difluoro substituents was the most potent, which selectively inhibited B-Raf (IC50: 57 nM) and B-RafV600E (IC50: 51 nM) over C-Raf (IC50: 1.0 μM). Compound 9m also actively inhibited EGFR (IC50: 73 nM) and VEGFR2 (IC50: 7.0 nM) but not EGFRT790M and PDGFR-β (IC50: >10 μM). Despite having good potency for B-Raf and B-RafV600E in the enzymatic assays, 9m was less active to inhibit melanoma A375 cells which proliferate due to constitutively activated B-Raf600E. The inferior activity of 9m for A375 was similar to that of sorafenib (6), suggesting that 9m might bind to the inactive conformations of B-Raf and B-RafV600E. Docking simulations could thus be performed to reveal the binding poses of 9m in B-Raf, B-RafV600E, and VEGFR2 kinases.

Pleurotus cornucopiae (Pleurotaceae) is an edible and medicinal mushroom widely distributed in Korea, China, and Japan. The MeOH extract of the fruiting bodies of P. cornucopiae showed renoprotective effects against cisplatin-induced kidney cell damage. Chemical investigation of the MeOH extract led to the isolation and identification of 12 compounds including noransine (1), uridine (2), uracil (3), (3β, 5α, 6β, 22E, 24S) -ergosta-7, 22-diene-3, 5, 6, 9-tetrol (4), (22E,24S)-ergosta-7,22-diene-3β,5α,6β-triol (5), (22E,24R)-ergosta-8(14),22-diene-3β,5α,6β,7α-tetrol (6), cerebroside B (7), (2R) -N- [(1S, 2R, 3E, 7E) -1- [(β-d-glucopyranosyloxy) methyl] -2-hydroxy-8-methyl-3, 7-heptadecadien-1-yl] -2-hydroxy-heptadecanamide (8), cerebroside D (9), nicotinamide (10), 1,2-bis(hydroxymethyl)-4,5-dimethoxybenzene (11), and benzoic acid (12). Among them, compounds 1 and 11 were isolated as naturally occurring products for the first time, though they were reported as synthetic products in previous papers. All of the compounds (except 8 and 11) abrogated cisplatin-induced LLC-PK1 cell damage in a dose-dependent manner. Of special note, compounds 2, 5, 6, and 12 ameliorated cisplatin-induced nephrotoxicity to 80% of the control value at 10μM. The protective effects of compounds 2, 5, 6, and 12 were mediated via the deactivation of JNK-caspase 3 apoptotic cascade. This study is the first to demonstrate that the chemical constituents of P. cornucopiae display renoprotective effects against anticancer drug-induced damage in kidney cells.

Cancer stem cells are responsible for the failure of a large number of cancer treatments and the re-emergence of cancer in patients. Parthenolide is a potent anticancer sesquiterpene lactone that is also able to kill cancer stem cells. The main problem with this compound is its poor solubility in water. To solve this problem, medicinal chemists have tried to prepare amino-derivatives of parthenolide, however, most amino-derivatives have less potency than that of parthenolide. In this paper, we proposed a new approach to synthesize parthenolide derivatives with better solubility and higher potency. We prepared novel parthenolide derivatives through the aza-Michael addition of nitrogen-containing anticancer drug molecules (cytarabine and melphalan) to the α-methylene-γ-lactone group of parthenolide. Different types of catalysts were used to catalyze the aza-Michael addition. Among all the used catalysts, 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) was found to have the highest catalytic activity. In addition, we examined the effects of parthenolide-anticancer drug hybrids on the growth and proliferation of three cancer cell lines (MCF-7, LNcaP, Hep G2) and CHO. The parthenolide prodrugs showed potent cytotoxic property with IC50 values ranging from 0.2 to 5.2μM, higher than those of parthenolide and anticancer drugs (cytarabine and melphalan).

The interaction of pyridoxine (Vitamin B6) with bovine serum albumin (BSA) is investigated under pseudo-physiological conditions by UV-Vis, fluorescence and FTIR spectroscopy. The intrinsic fluorescence of BSA was quenched by VB6, which was rationalized in terms of the static quenching mechanism. According to fluorescence quenching calculations, the bimolecular quenching constant (kq), dynamic quenching (KSV) and static quenching (KLB) at 310K were obtained. The efficiency of energy transfer and the distance between the donor (BSA) and the acceptor (VB6) were calculated by Foster's non-radiative energy transfer theory and were equal to 41.1% and 2.11nm. The collected UV-Vis and fluorescence spectra were combined into a row-and column-wise augmented matrix and resolved by multivariate curve resolution-alternating least squares (MCR-ALS). MCR-ALS helped to estimate the stoichiometry of interactions, concentration profiles and pure spectra for three species (BSA, VB6 and VB6-BSA complex) existed in the interaction procedure. Based on the MCR-ALS results, using mass balance equations, a model was developed and binding constant of complex was calculated using non-linear least squares curve fitting. FT-IR spectra showed that the conformation of proteins was altered in presence of VB6. Finally, the combined docking and molecular dynamics (MD) simulations were used to estimate the binding affinity of VB6 to BSA. Five-nanosecond MD simulations were performed on bovine serum albumin (BSA) to study the conformational features of its ligand binding site. From MD results, eleven BSA snapshots were extracted, at every 0.5ns, to explore the binding affinity (GOLD score) of VB6 using a docking procedure. MD simulations indicated that there is a considerable flexibility in the structure of protein that affected ligand recognition. Structural analyses and docking simulations indicated that VB6 binds to site I and GOLD score values depend on the conformations of both BSA and ligand. Molecular modeling results showed that VB6-BSA complex formed not only on the basis of electrostatic forces, but also on the basis of π-π staking and hydrogen bond. There was an excellent agreement between the experimental and computational results. The results presented in this paper, will offer a reference for detailed and systematic studies on the biological effects and action mechanism of small molecules with proteins.

Thermostability of monoclonal antibodies (mAbs) and antibody-drug conjugates (ADCs), as a critical property of biotherapeutics, is important for their physicochemical processes, pharmacodynamics, and pharmacokinetics. Fc glycosylation of mAbs plays a crucial role in antibody functions including thermostability, however, due to the lack of homogeneous glycosylation for comparison, the precise impact of glycoforms on thermostability of mAbs and ADCs remains challenging to elucidate. In this paper, we employed the technique of differential scanning fluorimetry (DSF) to investigate the thermostability of Fc domains, glycoengineered mAbs, and ADCs, carrying well-defined N-glycan structures for comparison. The results revealed that high-mannose-type N-glycans dramatically reduce the Tm value of Fc, compared to complex-type N-glycans. We also found that core-fucose contributes to the thermostability of mAbs, and the unnatural modification on non-reducing end of biantennary N-glycan can compensate the reduced stability of afucosylated mAbs and maintain the advantage of enhanced antibody-dependent cell-mediated cytotoxicity (ADCC). DSF analysis of lysine-linked and glycosite-specific ADCs indicated that thermostability of glycan-linked ADCs is reduced, but it could be improved by using an optimized linkage. This work provides an in-depth analysis on thermostability of mAbs and ADCs with homogeneous glycoforms, and also proposes new strategies for optimizing glycoengineered mAbs and glycosite-specific ADCs using unnatural glycan and stabilized linkage.

In this paper, the nitrogen atom was inserted into the anthracycline system of the isocryptolepine nucleus to obtain the “Aza”-type structure benzo[4,5]imidazo[1,2-c] quinazoline. A series of “Aza”-type derivatives were designed, synthesized and evaluated for their antifungal activity against six plant fungi in vitro. Among all derivatives, compounds A-0, B-1 and B-2 showed significant antifungal activity against B. cinerea with the EC50 values of 2.72 μg/mL, 5.90 μg/mL and 4.00 μg/mL, respectively. Compound A-2 had the highest activity against M. oryzae with the EC50 values of 8.81 μg/mL, and compound A-1 demonstrated the most control efficacy against R. solani (EC50, 6.27 μg/mL). Moreover, compound A-0 was selected to investigate the in vivo tests against B. cinerea and the results indicated that the preventative efficacy of it up to 72.80% at 100 μg/mL. Preliminary mechanism studies revealed that after treatment with A-0 at 5 µg/mL, the B. cinerea mycelia appeared curved, collapsed and the cell membrane integrity may be damaged. The reactive oxygen species production, mitochondrial membrane potential and nuclear morphometry of mycelia have been changed, and the membrane function and cell proliferation of mycelia were destroyed. Compounds A-0, A-1, B-1 and B-2 presented weaker toxicities against two cells lines than isocryptolepine. This study lays the foundation for the future development of isocryptolepine derivatives as environmentally friendly and safe agricultural fungicides.

In this research paper, we report the design and synthesis of novel substituted biscarbazole derivatives which were characterized by 1H and 13C NMR, high resolution mass spectroscopy (HRMS). The SAR study of the compounds is reported based on different substituents and their positions in the biscarbazole scaffold. In vitro cytotoxicity of the compounds was evaluated against human glioma U87 MG cell line by MTT assay for 24 h. The IC50 values of the compounds (30-35, 48-53 and 54-62) were calculated at the concentration range from 1.00 µM to 500 µM. The compound 34 showed the most significant in vitro cytotoxicity (IC50 = 3.9 µM) against human glioma U87 MG cell line and was found to be better than standard drugs used for the treatment of brain tumors such as temozolomide (IC50 = 100 µM) and carmustine (IC50 = 18.2 µM) respectively. To determine the mode of binding of compound 34 with CT-DNA, various biophysical techniques like UV-spectrophotometer, fluorescence, circular dichroism, viscosity, topoisomerase assay and molecular docking analysis, were used. Our results demonstrated groove binding mode of interaction of the compound 34 with CT-DNA with a plausible static bio-molecular quenching rate constant (Kq) 1.7 × 1012 M−1 s−1. The studies of biscarbazole derivatives are anticipated to develop potential novel anticancer agents against brain tumors.

The paper addressed shortcoming with highly precise and selective 3D structural analysis of native cyclodextrins in mixture using ions observable at low m/z–region by ESI– and APCI–mass spectrometry. Because of, the quantitative and structural analyses of CDs, in general, are vexed by a set of complications. The study outlines our own stochastic dynamic approaches to the latter issues based on new model relations, quantifing the measurable MS outcome intensity. They introduce the so–called stochastic dynamic mass spectrometric diffusion “DSD” parameter, exhibiting high accuracy, precision, sensitivity and selectivity, respectively. It is linearly connected with the so–called quantum chemical diffusion parameter “DQC” according to Arrhenius’s theory. The most important upshot is that statistical parameters r = 0.99639–0.99981 has been obtained correlating between DSD and DQC parameters. Therefore, we determine high accurately 3D molecular and electronic structures of analytes by mass spectrometry. Fragment peaks at m/z 313, 279, 272, 252, 231, 214, 198, 171, 158 and 141 are examined. Mixtures of CDs and monomeric and acyclic oligomer carbohydrates glucose (1), sucrose (2), raffinose (3), melezitose (4) and cellotriose (5) are also studied. Our method is able to account precisely for the effect of the temperature under ESI– and APCI–MS conditions, as well. Correlative analysess between DSD parameters of ESI– and APCI–MS measurements under different temperatures is also shown. Chemometric tests are used. Another important results and conclusions, among others, to draw from this research are: (i) excellent linear correlation between DSD and DQC parameters of r = 0.99636 is found looking at common ions at m/z 141, 158 and 171, belonging to 2-formyl-3,4-dihydroxy-pyranylium, 4,5,6-trihydroxy-6H-pyran-2-carbaldehyde and 3,4,5-trihydroxy-6-oxo-6H-pyran-2-ylmethylidyne-oxonium ions. Thus, we distinguish precisely between the last structure and 3-formyl-4,5-dihydroxy-2,7-dioxa-8-oxonia-bicyclo[4.2.0]octa-1(8),3,5-triene cation. In the case of ion at m/z 141 subtle electronic effects are distinguished between the mentioned structure and the charged 3,4-dihydroxy-6H-pyran-2-carbaldehyde one. The method determines precisely very similar structurally poly–OH–substituted derivatives. Because of, (ii) absolute reproducibility (r = 1) of DSD parameters of ESI–MS spectra is obtained studying the shown in point (i) MS peaks of β-CD between jth and jth numbers of experiments. The statistical equation is DiSD = (0.51 ± 3.1.10−5) × DjSD; (iii) the APCI– and ESI–MS provide identical results studying common MS ions of CDs and the correlation between DAPCISD and DESISD parameters excludes from error, due to, experiment; and (iv) The correlation between theory and experiment accounting for the factor temperature within our model equations shows r = 0.9828 looking at the MS peaks at m/z 313 280, 279, 274 and 252, respectively. The effect of the temperature under both ESI– and APCI–MS conditions on the 3D molecular and electronic structures of CDs is precisely studied, respectively.