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The M 3 muscarinic acetylcholine receptor (mAChR) plays an essential pharmacological role in mediating a broad range of actions of acetylcholine (ACh) released throughout the periphery and central nerve system (CNS). Nevertheless, its agonistic functions remain unclear due to the lack of available subtype-selective agonists or positive allosteric modulators (PAMs). In the course of our extended structure-activity relationships (SARs) study on 2-acylaminothiazole derivative 1, a previously reported PAM of the M 3 mAChR, we successfully identified N-pyrimidyl/pyridyl-2-thiazolamine analogues as new scaffolds. The SARs study was rationalized using conformational analyses based on intramolecular interactions. A comprehensive study of a series of analogues described in this paper suggests that a unique sulfur-nitrogen nonbonding interaction in the N-pyrimidyl/pyridyl-2-thiazolamine moiety enable conformations that are essential for activity. Further, a SARs study around the N-pyrimidyl/pyridyl-2-thiazolamine core culminated in the discovery of compound 3g, which showed potent in vitro PAM activity for the M 3 mAChR with excellent subtype selectivity. Compound 3g also showed a distinct pharmacological effect on isolated smooth muscle tissue from rat bladder and favorable pharmacokinetics profiles, suggesting its potential as a chemical tool for probing the M 3 mAChR in further research.

A series of novel 2-oxoquinoline derivatives containing arylaminothiazole were designed and synthesized as potential antitumor agents. The synthesized compounds were evaluated for their in vitro cytotoxicity activity against HeLa, NCI-H460, T24 and SKOV3 cancer cell lines using MTT assay. Among them, compound A7 exhibited the most potent activity against the test cancer cell lines, with the IC 50 values ranged from 4.4 to 8.7 µM. The results of tubulin polymerization assay showed that compound A7 could inhibit tubulin polymerization in vitro. Meanwhile, molecular docking study revealed that A7 can bind to the colchicine site of tubulin and formed hydrogen bonds with key amino acid residues in the active site. Further mechanism study demonstrated that compound A7 blocked cell cycle arrest at G2/M phase, induced cell apoptosis and depolarized mitochondria of HeLa cells. Collectively, our findings suggest that A7 could serve as a promising lead for the development of more efficient microtubule polymerization inhibitors for cancer therapy., (Copyright © 2020. Published by Elsevier Inc.)

Background: Cancer is second leading disease after cardiovascular disease. Presently, Chemotherapy, Radiotherapy and use of chemicals are some treatments available these days. Thiazole and its hybrid compounds extensively used scaffolds in drug designing and development of novel anticancer agents due to their wide pharmacological profiles. Fused thiazole scaffold containing drugs are available in market as a promising group of anticancer agents., Methods: The detailed study has been done using different database that focused on potent thiazole hybrid compounds with anticancer activity. The literature included in this review is focused on novel fused thiazole derivatives exhibiting anticancer potency in last decade., Results: Literature suggested that thiazoles and its fused and linked congener serve excellent pharmacological profile as an anticancer agent. Various synthetic strategies for fused thiazole are also summarized in this article. Novel thiazole and its fused congener showed anticancer activity against various cancer cell lines., Interpretation: Thiazole is a promising scaffold reported in literature with broad range of biological activities. This article covers the thiazole compounds fused with other carbocyclic/heterocycle including benzene, imidazole, pyridine, pyrimidine, quinoline, phenothiazine, thiopyrano, steroids, pyrrole etc. with anticancer activity from last decades. Several inhibitors for breast cancer, colon cancer, melanoma cancer, ovarian cancer, tubulin cancer etc. were reported in this review. Thus, this review will definitely aid to develop a lead for the new selective anticancer agents in future., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: After the approval of imatinib, more than 25 antitumor agents targeting kinases have been approved, and several promising candidates are at various stages of clinical evaluation., Objectives: Due to the importance of the thiazole scaffold in targeted anticancer drug discovery, the goal of this work is to identify new thiazolyl hydrazones as potent ABL1 kinase inhibitors for the management of Chronic Myeloid Leukemia (CML)., Methods: New thiazolyl hydrazones (2a-p) were synthesized and investigated for their cytotoxic effects on the K562 CML cell line. Compounds 2h, 2j and 2l showed potent anticancer activity against K562 cell line. The cytotoxic effects of these compounds on other leukemia (HL-60, MT-2 and Jurkat) and HeLa human cervical carcinoma cell lines were also investigated. Furthermore, their cytotoxic effects on Mitogen-Activated Peripheral Blood Mononuclear Cells (MA-PBMCs) were evaluated to determine their selectivity. Due to its selective and potent anticancer activity, compound 2j was benchmarked for its apoptosis-inducing potential on K562 cell line and inhibitory effects on eight different Tyrosine Kinases (TKs), including ABL1 kinase. In order to investigate the binding mode of compound 2j into the ATP binding site of ABL1 kinase (PDB: 1IEP), a molecular docking study was conducted using MOE 2018.01 program. The QikProp module of Schrödinger's Molecular modelling package was used to predict the pharmacokinetic properties of compounds 2a-p., Results: 4-(4-(Methylsulfonyl)phenyl)-2-[2-((1,3-benzodioxol-4-yl)methylene)hydrazinyl]thiazole (2j) showed antiproliferative activity against K562 cell line with an IC 50 value of 8.87±1.93 μM similar to imatinib (IC50= 6.84±1.11μM). Compound 2j was found to be more effective than imatinib on HL-60, Jurkat and MT-2 cells. Compound 2j also showed cytotoxic activity against HeLa cell line similar to imatinib. The higher selectivity index value of compound 2j than imatinib indicated that its antiproliferative activity was selective. Compound 2j also induced apoptosis in K562 cell line more than imatinib. Among eight TKs, compound 2j showed the strongest inhibitory activity against ABL1 kinase enzyme (IC 50 = 5.37±1.17μM). According to molecular docking studies, compound 2j exhibited high affinity to the ATP binding site of ABL1 kinase, forming significant intermolecular interactions. On the basis of in silico studies, this compound did not violate Lipinski's rule of five and Jorgensen's rule of three., Conclusion: Compound 2j stands out as a potential orally bioavailable ABL1 kinase inhibitor for the treatment of CML., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Pin1 is a peptidyl prolyl cis-trans isomerase (PPIase) and inhibiting Pin1 is a potential way for discovering anti-tumor agents. With an aim to find potent Pin1 inhibitors with a novel scaffold, a series of thiazole derivatives with an alicyclic heterocycles on the 2-position were designed, synthesized and tested against human Pin1. Compound 9p bearing a 2-oxa-6-azaspiro [3,3] heptane moiety on the thiazole scaffold was identified as the most potent Pin1 inhibitor of this series with an IC 50 value of 0.95 μM. The structure-activity relationship (SAR) and molecular modeling study indicated that introducing an alicyclic ring with an H-bond acceptor would be a viable way to improve the binding affinity., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Anti-virulence strategy is currently considered a promising approach to overcome the global threat of the antibiotic resistance. Among different bacterial virulence factors, the biofilm formation is recognized as one of the most relevant. Considering the high and growing percentage of multi-drug resistant infections that are biofilm-mediated, new therapeutic agents capable of counteracting the formation of biofilms are urgently required. In this scenario, a new series of 18 thiazole derivatives was efficiently synthesized and evaluated for its ability to inhibit biofilm formation against the Gram-positive bacterial reference strains Staphylococcus aureus ATCC 25923 and S. aureus ATCC 6538 and the Gram-negative strain Pseudomonas aeruginosa ATCC 15442. Most of the new compounds showed a marked selectivity against the Gram-positive strains. Remarkably, five compounds exhibited BIC 50 values against S. aureus ATCC 25923 ranging from 1.0 to 9.1 µM. The new compounds, affecting the biofilm formation without any interference on microbial growth, can be considered promising lead compounds for the development of a new class of anti-virulence agents.

Tuberculosis, an infectious disease, has been reported to cause the death of 1.5 million in 2018. Due to the emergence of Multi-Drug Resistant-TB, Extensively Drug Resistant-TB, and Totally Drug Resistant-TB, many first-line and second-line drugs have been found in-effective. New drugs introduced in TB regimens such as pretomanid, bedaquiline and linezolid have been associated with toxicities. Hence, there is an urgent need for introducing safe and cost-effective antitubercular drugs. In this study, a series of Schiff bases of 2-amino thiazoles were synthesized and evaluated for their anti-tubercular activity against Mycobacterium tuberculosis H37Rv strain by Microplate Alamar Blue assay (MABA) method. N-[4-(2-Amino-thiazol-4-yl)-phenyl]-benzamide derivative with 2-nitro (5c 2 ), 4-hydroxy (5c 4 ) substitution, 2-[4-(2-Amino-thiazol-4-yl)-phenyl]-isoindole-1,3-dione derivatives with 3,4,5-trimethoxy substitution (5b 1 ) and the compound 1-[4-(2-Amino-thiazol-4-yl)-phenyl]-pyrrole-2,5-dione (4a) which is a maleic derivative bearing thiazole ring, exhibited good anti-tubercular activity (MIC 6.25 μg/ml). Drug likeness was also evaluated for all the synthesised compounds using Molinspiration software. All synthesized compounds fulfilled the parameters of the Lipinski rule of five and showed drug-like properties. Through this study, it was proved that thiazole analogues have good anti-tubercular potentials., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Novel 2-indolinone thiazole hybrids were designed and synthesized as VEGFR-2 inhibitors based on sunitinib, an FDA-approved anticancer drug. The proposed structures of the prepared 2-indolinone thiazole hybrids were confirmed based on their spectral data and CHN analyses. The target compounds were screened in vitro for their anti-VEGFR-2 activity. All tested compounds exhibited a potent submicromolar inhibition of VEGFR-2 kinase with IC 50 values ranging from 0.067 to 0.422 μM, relative to sunitinib reference drug (IC 50  = 0.075 ± 0.002 μM). Compounds 5, 15a, 15b, 17, 19c displayed excellent VEGFR-2 inhibitory activity, comparable or nearly equipotent to sunitinib. Compound 13b stood out as the most potent against VEGFR-2 showing IC 50 value of 0.067 ± 0.002 μM, lower than that of sunitinib. In addition, the most potent derivatives were assessed for their anticancer activity against two renal cancer cell lines. Compound 13b (IC 50  = 3.9 ± 0.13 μM) was more potent than sunitinib (IC 50  = 4.93 ± 0.16 μM) against CAKI-1 cell line. Moreover, thiazole 15b displayed excellent anticancer activity against CAKI-1 cell line (IC 50  = 3.31 ± 0.11 μM), superior to that of sunitinib (IC 50  = 4.93 ± 0.16 μM). Thiazole 15b was also equipotent to sunitinib (IC 50  = 1.23 ± 0.04 μM) against A498 cell line. Besides, compound 15b revealed a safety profile much better than that of sunitinib against normal human renal cells. Furthermore, a docking study revealed a proper fitting of the most active compounds into the ATP binding site of VEGFR-2, rationalizing their potent anti-VEGFR-2 activity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Rising numbers of cases of multidrug- and extensively drug-resistant Pseudomonas aeruginosa over recent years have created an urgent need for novel therapeutic approaches to cure potentially fatal infections. One such approach is virulence attenuation where anti-virulence compounds, designed to reduce pathogenicity without affording bactericidal effects, are employed to treat infections. P. aeruginosa uses the pqs quorum sensing (QS) system, to coordinate the expression of a large number of virulence determinants as well as bacterial-host interactions and hence represents an excellent anti-virulence target. We report the synthesis and identification of a new series of thiazole-containing quinazolinones capable of inhibiting PqsR, the transcriptional regulator of the pqs QS system. The compounds demonstrated high potency (IC 50  < 300 nM) in a whole-cell assay, using a mCTX:P pqsA -lux-based bioreporter for the P. aeruginosa PAO1-L and PA14 strains. Structural evaluation defined the binding modes of four analogues in the ligand-binding domain of PqsR through X-ray crystallography. Further work showed the ability of 6-chloro-3((2-pentylthiazol-4-yl)methyl)quinazolin-4(3H)-one (18) and 6-chloro-3((2-hexylthiazol-4-yl)methyl)quinazolin-4(3H)-one (19) to attenuate production of the PqsR-regulated virulence factor pyocyanin. Compounds 18 and 19 showed a low cytotoxic profile in the A549 human epithelial lung cell line making them suitable candidates for further pre-clinical evaluation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

We describe here our efforts to develop a PET tracer for imaging GluN2A-containing NMDA receptors, based on a 5H-thiazolo[3,2-α]pyrimidin-5-one scaffold. The metabolic stability and overall properties could be optimized satisfactorily, although binding affinities remained a limiting factor for in vivo imaging. We nevertheless identified 7-(((2-fluoroethyl)(3-fluorophenyl)amino)-methyl)-3-(2-(hydroxymethyl)cyclopropyl)-2-methyl-5H-thiazolo-[3,2-α]pyrimidin-5-one ([ 18 F]7b) as a radioligand providing good-quality images in autoradiographic studies, as well as a tritiated derivative, 2-(7-(((2-fluoroethyl)(4-fluorophenyl)amino)methyl)-2-methyl-5-oxo-5H-thiazolo[3,2-α]pyrimidin-3-yl)cyclopropane-1-carbonitrile ([ 3 H 2 ]15b), which was used for the successful development of a radioligand binding assay. These are valuable new tools for the study of GluN2A-containing NMDA receptors, and for the optimization of allosteric modulators binding to the pharmacophore located at the dimer interface of the GluN1-GluN2A ligand-binding domain., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A small series of 2,4-dioxothiazolidinyl acetic acids was prepared from thiourea, chloroacetic acid, aromatic aldehydes, and ethyl-2-bromoacetate. They were assayed for the inhibition of four physiologically relevant carbonic anhydrase (CA, EC 4.2.1.1) isoforms of human (h) origin, the cytosolic hCA I and II, and the transmembrane hCA IX and XII, involved among others in tumorigenesis (hCA IX and XII) and glaucoma (hCA II and XII). The two cytosolic isoforms were not inhibited by these carboxylates, which were also rather ineffective as hCA IX inhibitors. On the other hand, they showed submicromolar hCA XII inhibition, with K I s in the range of 0.30-0.93 µM, making them highly CA XII-selective inhibitors.

An improved pharmacophore model, molecular properties, geometric analyses, and SAR led to synthesize oxazolo/thiazolo-[3,2-a]-pyrimidin-3(2H)-one, and 1,5-dihydroimidazo-[1,2-a]-pyrimidin-3(2H)-one derivatives exhibiting potent anti-hypertensive activity. The 6-ethoxycarbonyl-2,7-dimethyl-5-phenyl-1,5-dihydroimidazo[3,2-a]pyrimidin-3(2H)-one (4g), and 6-ethoxycarbonyl-2,7-dimethyl-5-(3-methyl-phenyl)-1,5-dihydroimidazo[3,2-a]pyrimidin-3(2H)-one (4h) showed significant reduction in mean arterial blood pressure (MABP, mm/Hg) of 79.78%, and 92.95% in 6 and 12 h durations, respectively, at 1.5 mg/kg body-weight dose, while at 3.0 mg/kg body-weight dose, the MABP reduction was achieved at 95.46%, and 92.02%, respectively, in 6 and 12 h durations, as compared to the standard drug, nifedipine., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The synthesis, anti-inflammatory and antioxidant properties of novel 5-hydroxy-7-methyl-3H-thiazolo[4,5-b]pyridin-2-one derivatives were discussed. Fused thiazolo[4,5-b]pyridin-2-ones were synthesized and modified at the N3, C5 and C6 positions of the main core in order to obtain the compounds with a satisfactory pharmacological profile. The synthesized compounds were preselected via molecular docking for further testing of their anti-inflammatory activity in vitro. Evaluation of novel compounds over the carageenin induced rat paw edema revealed strong anti-inflammatory action of some compounds including (thiazolo[4,5-b]pyridin-3(2H)-yl) propanenitrile (5) and thiazolo[4,5-b]pyridin-3(2H)-yl) propanoic acid (6) even exceeding the standard - Ibuprofen. The antioxidant activity of the synthesized compounds was measured in vitro by the method of scavenging effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals.

In the present study, new series of thiazolopyrimidine derivatives was synthesized as purine analogs. The structures of the products were confirmed through spectroscopic techniques such as NMR and mass spectrometry. In addition, the synthesized compounds were evaluated as antitumor active agent through NCI screening protocol against 60 different cell lines under 9 different panels. Furthermore, DNA binding activity of the compounds was also evaluated. The results revealed that compound 35 proved to be the most active member of the tested series and it is promoted to the 5-dose testing where it gives GI 50 , TGI and LC 50 values of 1.07, 6.61, 34.7 μM respectively. Furthermore, it also proved to have a good DNA binding activity with value that is comparable with that produced by doxorubicin which was used as positive standard. In addition, compound 27 was proved to be the most active DNA binding agent with binding affinity 28.38 ± 1.1. The pharmacokinetic properties were also calculated. Molecular docking studies suggested binding mode of compounds 27 and 35 to DNA minor groove via hydrogen bonding interaction. The anticancer activity of compounds 27 and 35 may be attributed to DNA binding., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Aldose reductase (AR) is the first and rate-limiting enzyme of the polyol pathway, which converts glucose to sorbitol in an NADPH-dependent reaction. α-Glycosidase breaks down starch and disaccharides to glucose. Hence, inhibition of these enzymes can be regarded a considerable approach in the treatment of diabetic complications. AR was purified from sheep liver using simple chromatographic methods. The inhibitory effects of pyrazolyl-thiazoles ((3aR,4S,7R,7aS)-2-(4-{1-[4-(4-bromophenyl)thiazol-2-yl]-5-(aryl)-4,5-dihydro-1H-pyrazol-3-yl}phenyl)-3a,4,7,7a-tetrahydro-1H-4,7-methanoisoindole-1,3(2H)-dione derivatives; 3a-i) on AR and α-glycosidase enzymes were investigated. All compounds showed a good inhibitory action against AR and α-glycosidase. Among these compounds, compound 3d exhibited the best inhibition profiles against AR, with a K i value of 7.09 ± 0.19 µM, whereas compound 3e showed the lowest inhibition effects, with a K i value of 21.89 ± 1.87 µM. Also, all compounds showed efficient inhibition profiles against α-glycosidase, with K i values in the range of 0.43 ± 0.06 to 2.30 ± 0.48 µM, whereas the K i value of acarbose was 12.60 ± 0.78 µM. Lastly, molecular modeling approaches were implemented to predict the binding affinities of compounds against AR and α-glycosidase. In addition, the ADME analysis of the molecules was performed., (© 2020 Deutsche Pharmazeutische Gesellschaft.)

A series of 17 compounds ( 12-16 b ) with 2,4,5-trisubstitutedthiazole scaffold having 5-aryl group, 4-carboxylic acid/ester moiety, and 2-amino/amido/ureido functional groups were synthesised, characterised, and evaluated for their carbonic anhydrase (CA)-III inhibitory activities using the size exclusion Hummel-Dreyer method (HDM) of chromatography. Compound 12a with a free amino group at the 2-position, carboxylic acid moiety at the 4-position, and a phenyl ring at the 5-position of the scaffold was found to be the most potent CA-III inhibitor ( K i = 0.5 μM). The presence of a carboxylic acid group at the 4-position of the scaffold was found to be crucial for the CA-III inhibitory activity. Furthermore, replacement of the free amino group with an amide and urea group resulted in a significant reduction of activity (compounds 13c and 14c , K i = 174.1 and 186.2 μM, respectively). Thus, compound 12a (2-amino-5-phenylthiazole-4-carboxylic acid) can be considered as the lead molecule for further modification and development of more potent CA-III inhibitors.

A facile synthesis of a group of novel thiazole-pyrazolone hybrids and their investigation for angiotensin-converting enzyme (ACE) inhibition are reported in this study. These compounds were synthesized using a well-known approach, based on the condensation of ethyl acetoacetate with thiazolylhydrazines, and characterized by various spectroscopic and analytical techniques. The entire set of compounds displayed a moderate-to-excellent inhibitory activity against ACE. In particular, compound 4i was found to be the most potent ACE inhibitor and was further studied for cardioprotective effects against isoproterenol (ISO)-induced myocardial infarction (MI) in rats. Compound 4i improved the cardiac function and prevented cardiac injury induced by ISO in Sprague Dawley rats. The levels of oxidative stress and proinflammatory cytokines were also restored to near normal by 4i as compared with the ISO group. In the Western blot analysis, compound 4i prevented mitochondrial apoptosis after MI by downregulating the expression of cleaved caspase-3 and Bax, with the upregulation of Bcl-2, as compared with the ISO group., (© 2020 Deutsche Pharmazeutische Gesellschaft.)

A series of novel (5R)-5-((2S,3S)-3-((1-(4-chlorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-3,6-dihydro-2H-pyran-2-yl)-3-(4-fluorophenyl)-2,6-diphenyl-3,3a,5,6-tetrahydro-2H-pyrazolo[3,4-d]thiazoles 11a-g and (5R)-5-((2S,3S)-3-((1-(4-chlorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-3,6-dihydro-2H-pyran-2-yl)-3-(4-fluorophenyl)-6-phenyl-3,3a,5,6-tetrahydroisoxazolo[3,4-d]thiazoles 12a-g were synthesized by the reaction of chalcone derivatives of (R,Z)-2-((2S,3S)-3-((1-(4-chlorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-3,6-dihydro-2H-pyran-2-yl)-5-(4-fluorobenzylidene)-3-phenylthiazolidin-4-ones 10a-g with phenylhydrazine and hydroxylamine hydrochloride. The chemical structures of newly synthesized compounds were elucidated by IR, NMR, MS and elemental analysis. The compounds 11a-g and 12a-g were evaluated for their antibacterial activity and antifungal activity.

We have previously reported the discovery of a series of rhodanine-based inhibitors of the PIM family of serine/threonine kinases. Here we described the optimisation of those compounds to improve their physicochemical and ADME properties as well as reducing their off-targets activities against other kinases. Through molecular modeling and systematic structure activity relationship (SAR) studies, advanced molecules with high inhibitory potency, reduced off-target activity and minimal efflux were identified as new pan-PIM inhibitors. One example of an early lead, OX01401, was found to inhibit PIMs with nanomolar potency (15 nM for PIM1), inhibit proliferation of two PIM-expressing leukaemic cancer cell lines, MV4-11 and K562, and to reduce intracellular phosphorylation of a PIM substrate in a concentration dependent manner., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Alzheimer's disease (AD) is a complex, predominant, and progressive form of dementia. The treatment of AD alters depending on the cognitive and behavioral symptoms. The utility of cholinergic replacement by acetylcholinesterase (AChE) inhibitors in AD treatment has been well-documented so far. Recent studies have also demonstrated that human carbonic anhydrases (hCAs) serve as important targets for AD treatment. In an attempt to identify potent AChE and hCA inhibitors, new thiazolyl-pyrazolines (3a-k) were designed based on the molecular hybridization of thiazole and pyrazoline scaffolds. A facile and versatile synthetic route consisting of three steps, namely Claisen-Schmidt reaction, the formation of the 2-pyrazoline ring system, and Hantzsch thiazole synthesis was used to prepare compounds 3a-k. The synthesized derivatives were experimentally validated for efficacy by in vitro and direct enzymatic assays. Furthermore, the compounds were subjected to in silico screening using Schrödinger Suite software to identify the binding affinities of potential compounds based on Glide XP scoring, MM-GBSA calculating, and validation. The results of in vitro and in silico studies revealed that compounds 3a, 3f, and 3d were the most promising derivatives in this series due to their significant effects on AChE, hCA I, and hCA II, respectively., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Cystic fibrosis is a genetic disease caused by loss-of-function mutations in the cystic fibrosis transmembrane conductance regulator gene, encoding for CFTR protein. The most frequent mutation is the deletion of phenylalanine at position 508 (F508del), which leads to distinct defects in channel gating and cellular processing. In last years, several thiazole containing small molecules, endowed with dual F508del-CFTR modulator activity, proved to be able to target these defects. In search of new chemical entities able to restore CFTR function, we designed and synthesized a small series of sixteen thiazole derivatives. The designed compounds were studied as correctors and potentiators of F508del-CFTR. Although none of the molecules showed significant corrector activity, compounds 10 and 11 exhibited potentiator effects, thus allowing to determine some basic structural features which enable to obtain F508del-CFTR potentiator activity. In silico ADME studies showed that these derivatives obey Lipinski's rule of five and are expected to be orally bioavailable. Therefore, these molecules may represent a good starting point for the design of analogues endowed with improved CFTR potentiator activity and a good pharmacokinetic profile., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Bioluminescence imaging (BLI) is useful to monitor cell movement and gene expression in live animals. However, D-luciferin has a short wavelength (560 nm) which is absorbed by tissues and the use of near-infrared (NIR) luciferin analogues enable high sensitivity in vivo BLI. The AkaLumine-AkaLuc BLI system (Aka-BLI) can detect resolution at the single-cell level; however, it has a clear hepatic background signal. Here, to enable the highly sensitive detection of bioluminescence from the surrounding liver tissues, we focused on seMpai (C 15 H 16 N 3 O 2 S) which has been synthesized as a luciferin analogue and has high luminescent abilities as same as AkaLumine. We demonstrated that seMpai BLI could detect micro-signals near the liver without any background signal. The solution of seMpai was neutral; therefore, seMpai imaging did not cause any adverse effect in mice. seMpai enabled a highly sensitive in vivo BLI as compared to previous techniques. Our findings suggest that the development of a novel mutated luciferase against seMpai may enable a highly sensitive BLI at the single-cell level without any background signal. Novel seMpai BLI system can be used for in vivo imaging in the fields of life sciences and medicine.

B-Raf mutation was identified as a key target in cancer treatment. Based on structural features of dabrafenib (potent FDA approved B-Raf inhibitor), the design of new NH 2 -based imidazothiazole derivatives was carried out affording new highly potent derivatives of imidazothiazole-based scaffold with amino substitution on the terminal phenyl ring as well as side chain with sulfonamide group and terminal substituted phenyl ring. In vitro enzyme assay was investigated against V600E B-Raf kinase. Compounds 10l, 10n and 10o showed higher inhibitory activities (IC 50  = 1.20, 4.31 and 6.21 nM, respectively). In vitro cytotoxicity evaluation was assessed against NCI-60 cell lines. Most of tested derivatives showed cytotoxic activities against melanoma cell line. Compound 10k exhibited most potent activity (IC 50  = 2.68 µM). Molecular docking study revealed that the new designed derivatives preserved the same binding mode of dabrafenib with V600E B-Raf active site. It was investigated that the new modification in the synthesized derivatives (substituted with NH 2 ) had a significant inhibitory activity towards V600E B-Raf. This core scaffold is considered a key compound for further structural and molecular optimization., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

A series of 4-aryl-5-aminoalkyl-thiazole-2-amines were designed and synthesized, and their inhibitory activity on ROCK II was screened by enzyme-linked immunosorbent assay (ELISA). The results showed that 4-aryl-5-aminomethyl-thiazole-2-amines derivatives had certain ROCK II inhibitory activities. Compound 10l showed ROCK II inhibitory activity with IC 50 value of 20 nM., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Aim: With the increasing emergence of drug-resistant bacteria, the need for new antimicrobial agents has become extremely urgent. This work was to develop sulfonyl thiazoles as potential antibacterial agents. Results & methodology: Novel hybrids of sulfonyl thiazoles were developed from commercial acetanilide and acetylthiazole. Hybrids 6e and 6f displayed excellent inhibitory efficacy against clinical methicillin-resistant Staphylococcus aureus (MRSA) (minimum inhibitory concentration = 1 μg/ml) without obvious toxicity toward normal mammalian cells (RAW 264.7). The combination uses were found to improve the antimicrobial ability. Further preliminary antibacterial mechanism experiments showed that the active molecule 6f could effectively interfere with MRSA membrane and insert into MRSA DNA. Conclusion: Compounds 6e and 6f could serve as potential DNA-targeting templates toward the development of promising antimicrobial agents.

New compounds containing thiazole and pyridinium moieties were designed and synthesized. The potency of the synthesized compounds as selective inhibitors of acetylcholinesterase (AChE), and β-amyloid aggregation (Aβ) was evaluated. Compounds 7d and 7j showed the best AChE inhibitory activities at the submicromolar concentration range (IC 50  values of 0.40 and 0.69 μM, respectively). Most of the novel compounds showed moderate to low inhibition of butyrylcholinesterase (BChE), which is indicative of their selective inhibitory effects towards AChE. Kinetic studies using the most potent compounds 7d and 7j confirmed a mixed-type of AChE inhibition mechanism in accordance with the docking results, which shows their interactions with both catalytic active (CAS) and peripheral anionic (PAS) sites. The specific binding of 7a, 7j, and 7m to PAS domain of AChE was also confirmed experimentally. In addition, 7d and 7j were able to show β-amyloid self-aggregation inhibitory effects (20.38 and 42.66% respectively) stronger than donepezil (14.70%) assayed at 10 μM concentration. Moreover, compounds 7j and 7m were shown to be effective neuroprotective agents in H 2 O 2 -induced oxidative stress on PC 12 cells almost similar to those observed for donepezil. The ability of 7j to pass blood-brain barrier was demonstrated using the PAMPA method. The results presented in this work provide useful information about designing novel anti-Alzheimer agents., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

A series of novel oxo-hydrazone and spirocondensed-thiazolidine derivatives of imidazo[2,1-b]thiazole were synthesized and evaluated for their antioxidant activity. The antioxidant activity of 18 newly synthesized compounds and 12 previously reported compounds bearing similar scaffold, were evaluated by three different methods: inhibition of FeCl 3 /ascorbate system-induced lipid peroxidation of lecithin liposome (anti-LPO), scavenging activity against ABTS radical and Ferric Reducing Antioxidant Power (FRAP) activity. 4h, 5h, and 6h displayed the highest anti-LPO and ABTS radical removal activity. Also, in FRAP analysis, 4i and 4a displayed the best activity. In addition to the in vitro analysis, docking studies targeting the active site of Human peroxiredoxin 5 (PDB ID: 1HD2) were employed to explore the possible interactions of these compounds with the receptor. Structure-activity relationships, as well as virtual ADME studies, were carried out and a relationship between biological, electronic, and physicochemical qualifications of the target compounds was determined., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Financial & competing interests disclosure The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discusses in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. No writing assistance was utilized in the production of this manuscript., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The synthesis of new analogues of cyclolinopeptide A (CLA) and their linear precursors modified with (R)- and (S)-4-methylpseudoproline in the Pro 3 -Pro 4 fragment are presented. The peptides were tested in comparison with cyclosporine A (CsA) in concanavalin A (Con A) and pokeweed mitogen (PWM)-induced mouse splenocyte proliferation and in secondary humoral immune response in vitro to sheep erythrocytes (SRBC). Their effects on expression of selected signaling molecules in the Jurkat T cell line were also determined. In addition, the structural features of the peptides, applying nuclear magnetic resonance and circular dichroism, were analyzed. The results showed that only peptides 7 and 8 modified with (R)-4-methylpseudoproline residue (c(Leu 1 -Val 2 -(R)-(αMe)Ser(ΨPro) 3 -Pro 4 -Phe 5 -Phe 6 -Leu 7 -Ile 8 -Ile 9 ) and c(Leu 1 -Val 2 -Pro 3 -(R)-(αMe)Ser(ΨPro) 4 -Phe 5 -Phe 6 -Leu 7 -Ile 8 -Ile 9 ), respectively) strongly suppressed mitogen-induced splenocyte proliferation and the humoral immune response, with peptide 8 being more potent. Likewise, peptide 8 more strongly elevated expression of Fas, a proapoptotic signaling molecule in Jurkat cells. We postulate that the increased biological activity of peptide 8, compared to the parent molecule and other studied peptides, resulted from its more flexible structure, found on the basis of both CD and NMR studies. CD and NMR spectra showed that replacement of Pro 3 by (R)-(αMe)Ser(¬Pro) caused much greater conformational changes than the same replacement of the Pro 4 residue. Such a modification could lead to increased conformational freedom of peptide 8, resulting in a greater ability to adopt a more compact structure, better suited to its putative receptor. In conclusion, peptide 8 is a potent immune suppressor which may find application in controlling immune disorders., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Dementia is a neurological condition commonly correlated with Alzheimer's disease (AD), and it is seen with many other central nervous system (CNS) disorders. The restricted number of medications is not appropriate to offer enough relief to enhance the quality of life of patients suffering from this symptom; thus, all therapeutic choices should be carefully assessed. In this study, new thiazolylhydrazone derivatives ( 2a - 2l ) were designed and synthesized based on the cholinergic hypothesis. Their chemical structures were confirmed by 1 H NMR, 13 C NMR, and HRMS spectrometric techniques. The ADME (absorption, distribution, metabolism, elimination) parameters of the synthesized compounds were predicted by using QikProp 4.8 software. It was concluded that all compounds presented satisfactory drug-like characteristics. Furthermore, their inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in vitro were also tested by modified the Ellman spectrophotometric method. According to the results, all compounds showed a weak inhibitory effect on BChE. On the other hand, most of the compounds ( 2a , 2b , 2d , 2e , 2g , 2i , and 2j ) had a certain AChE inhibitory activity, and the IC 50 values of them were calculated as 0.063 ± 0.003, 0.056 ± 0.002, 0.147 ± 0.006, 0.040 ± 0.001, 0.031 ± 0.001, 0.028 ± 0.001, and 0.138 ± 0.005 µM, respectively. Among these derivatives, compound 2i was found to be the most active agent in the series with an IC 50 value of 0.028 ± 0.001 µM, which indicated an inhibition profile at a similar rate as the reference drug, donepezil. The potential binding modes of compounds 2a , 2b , 2e , 2g , and 2i with AChE were investigated and compared with each other by the molecular docking studies. The results showed that these compounds were strongly bound up with the AChE enzyme active site with the optimal conformations.

The increasing emergence of antibiotic-resistant bacterial pathogens calls for additional urgency in the development of new antibacterial candidates. N-Phenyl-2-aminothiazoles are promising candidates that possess potent anti-MRSA activity and could potentially replenish the MRSA antibiotic pipeline. The initial screen of a series of compounds in this novel class against several bacterial strains revealed that the aminoguanidine analogues possessed promising activities and superior safety profiles. The determined MICs of these compounds were comparable to, if not better than, those of the control drugs (linezolid and vancomycin). Remarkably, compounds 3a, 3b, and 3e possessed potent activities against multidrug resistant staphylococcal isolates and several clinically important pathogens, such as vancomycin-resistant enterococci (VRE) and Streptococcus pneumoniae. In addition, the compounds were superior to vancomycin in the rapid killing of MRSA and the longer post-antibiotic effects. Furthermore, low concentrations of compounds 3a, 3b, and 3e reduced the intracellular burden of MRSA by greater than 90%. Initial in vitro PK/toxicity assessments revealed that compound 3e was highly tolerable and possessed a low metabolic clearance rate and a highly acceptable half-life., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

The capsid assembly is a significant phase for the hepatitis B virus (HBV) lifespan and is an essential target for anti-HBV drug discovery and development. Herein, we used scaffold hopping, bioisosterism, and pharmacophore hybrid-based strategies to design and synthesize six series of various heterocycle derivatives (pyrazole, thiazole, pyrazine, pyrimidine, and pyridine) and screened for in vitro anti-HBV non-nucleoside activity. Drug candidate NZ-4 and AT-130 were used as lead compounds. Several compounds exhibited prominent anti-HBV activity compared to lead compound NZ-4 and positive drug Lamivudine, especially compound II-8b, showed the most prominent anti-HBV DNA replication activity (IC 50  = 2.2 ± 1.1 μM). Also compounds IV-8e and VII-5b showed the best in vitro anti-HBsAg secretion (IC 50  = 3.8 ± 0.7 μM, CC 50  > 100 μM) and anti-HBeAg secretion (IC 50  = 9.7 ± 2.8 μM, CC 50  > 100 μM) respectively. Besides, II-8b can interact HBV capsid protein with good affinity constants (K D  = 60.0 μM), which is equivalent to lead compound NZ-4 ((K D  = 50.6 μM). The preliminary structure-activity relationships (SARs) of the newly synthesized compounds were summarized, which may help researchers to discover more potent anti-HBV agents., Competing Interests: Declaration of competing interest The authors declared that they have no conflicts of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

An easy access to a series of N-phenylmorpholine derivatives linked with thiazole or formazan moieties were achieved using simple experimental procedure under conventional and microwaves irradiation conditions. The reaction of 2-(N-phenylmorpholine)ethylidene)hydrazine-1-carbothioamide derivatives and [1-(4-morpholin-4-yl-phenyl)-ethylidene]-hydrazine with a variety of hydrazonoyl chlorides or phenacyl bromide derivatives afforded the corresponding thiazoles or N-substitutedhydrazino-derivatives linked to N-phenylmorpholine moiety in good to excellent yields. The structures of the newly synthesized compounds were fully emphasized and characterized by spectroscopic as well as elemental analyses. The mode of binding of some selected compounds with SS-DNA was evaluated using UV-Vis absorption, and viscosity measurements. The results showed intercalation binding mode of most of the tested compounds. Both antimicrobial and anti-cancer activities have been studied for some selected compounds from synthetic derivatives. Their results showed a remarkable efficacy for some derivatives against both examined microbes and cancer cells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

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 IC 50 value of 0.17 ± 0.01 µM. Additionally, compounds 5a and 5i were found to be highly selective toward h-TNAP with IC 50 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 IC 50 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., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Aldose reductase (AR) catalyzes the NADPH-dependent reduction of glucose to sorbitol in the polyol pathway, which plays an important role in the development of diabetic complications including cataract, retinopathy, nephropathy, and neuropathy. AR has been considered as an important target to heal these long-term diabetic complications and for this reason the development of new AR inhibitors is an important approach in modern medicinal chemistry. In the current study, new 4-aryl-2-[2-((3,4-dihydro-2H-1,5-benzodioxepine-7-yl)methylene)hydrazinyl]thiazole derivatives (1-12) were synthesized and screened for their inhibitory effects on AR which was purified by diverse chromatographic methods with a yield of 1.40% and a specific activity of 2.00 EU/mg. All compounds were determined as promising AR inhibitors with the K i values in the range of 0.018 ± 0.005 μM-3.746 ± 1.321 μM compared to the quercetin (K i  = 7.025 ± 1.780 μM). In particular, 4-(4-cyanophenyl)-2-[2-((3,4-dihydro-2H-1,5-benzodioxepin-7-yl)methylene)hydrazinyl]thiazole (3) was detected as the most potential AR inhibitor in this series with the K i value of 0.018 ± 0.005 µM and the compound showed competitive AR inhibition. The cytotoxic effects of compounds 1-12 were investigated on L929 mouse fibroblast (healthy) cells using MTT assay and all these compounds were defined as non-cytotoxic agents against L929 cells. Molecular docking studies, which were employed to determine the affinity of compounds 1-12 into the active site of AR, highlighted that the thiazole scaffold of all these compounds presented π-π stacking interactions with Trp20 and Phe122. According to both in vitro and in silico assays, these potential AR inhibitors may have great importance in the prevention of diabetic microvascular conditions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Aim: Tryptophan hydroxylase 1 (TPH1) catalyzes serotonin synthesis in peripheral tissues. Selective TPH1 inhibitors may be useful for treating disorders related to serotonin dysregulation. Results & methodology: Screening using a thermal shift assay for TPH1 binders yielded Compound 1 (2-(4-methylphenyl)-1,2-benzisothiazol-3(2 H )-one), which showed high potency (50% inhibition at 98 ± 30 nM) and selectivity for inhibiting TPH over related aromatic amino acid hydroxylases in enzyme activity assays. Structure-activity relationships studies revealed several analogs of 1 showing comparable potency. Kinetic studies suggested a noncompetitive mode of action of 1 , with regards to tryptophan and tetrahydrobiopterin. Computational docking studies and live cell assays were also performed. Conclusion: This TPH1 inhibitor scaffold may be useful for developing new therapeutics for treating elevated peripheral serotonin.

A series of thiazolopyrimidine derivatives was designed and synthesized as a Leishmania major pteridine reductase 1 (LmPTR1) enzyme inhibitor. Their LmPTR1 inhibitor activities were evaluated using the enzyme produced by Escherichia coli in a recombinant way. The antileishmanial activity of the selected compounds was tested in vitro against Leishmania sp. Additionally, the compounds were evaluated for cytotoxic activity against the murine macrophage cell line RAW 264.7. According to the results, four compounds displayed not only a potent in vitro antileishmanial activity against promastigote forms but also low cytotoxicity. Among them, compound L16 exhibited an antileishmanial activity for both the promastigote and amastigote forms of L. tropica, with IC 50 values of 7.5 and 2.69 µM, respectively. In addition, molecular docking studies and molecular dynamics simulations were also carried out in this study. In light of these findings, the compounds provide a new potential scaffold for antileishmanial drug discovery., (© 2020 Deutsche Pharmazeutische Gesellschaft.)

This paper presents the synthesis and glucokinase activity of novel hydrazone derivatives. The 2-(4-cyclopropylsulfonylphenyl)-2-[(E)-pyrrolidin-1-ylimino]-acetamide derivatives 5a-5h presented the in vitro glucokinase activities and in vivo blood glucose-lowering effects in mice. Particularly, 5h showed an oral hypoglycemic effect in rats at 1 mg/kg. These hydrazone derivatives are a potential new class of glucokinase activators for the treatment of type 2 diabetes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Bromodomain-containing protein 4 (BRD4) is a key epigenetic regulator in cancer, and inhibitors targeting BRD4 exhibit great anticancer activity. By replacing the methyltriazole ring of the BRD4 inhibitor I-BET-762 with an N-methylthiazolidone heterocyclic ring, fifteen novel BRD4 inhibitors were designed and synthesized. Compound 13f had a hydrophobic acetylcyclopentanyl side chain, showing the most potent BRD4 inhibitory activity in the BRD4-BD1 inhibition assay (IC 50 value of 110 nM), it also significantly suppressed the proliferation of MV-4-11 cells with high BRD4 level (IC 50 value of 0.42 μM). Furthermore, the potent apoptosis-promoting and G0/G1 cycle-arresting activity of compound 13f were indicated by flow cytometry. As the downstream-protein of BRD4, c-Myc was in significantly low expression by compound 13f treatment in a dose-dependent manner. All the findings supported that this novel compound 13f provided a perspective for developing effective BRD4 inhibitors., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

A series of fluorescent thiazole-pyrazoline derivatives was synthesized and their structures were characterized by 1 H NMR, 13 C NMR, and HRMS. Biological evaluation demonstrated that these compounds could effectively inhibit the growth of human non-small cell lung cancer (NSCLC) A549 cells in a dose- and time-dependent manner in vitro and inhibit tumor growth in vivo. The structure-activity relationship (SAR) of the compounds was analyzed. Further mechanism research revealed they could induce autophagy and cell cycle arrest while had no influence on cell necrosis. Compound 5e inhibited the activity of mTOR via FKBP12, which could be reversed by 3BDO, an mTOR activator and autophagy inhibitor. Compound 5e inhibited growth, promoted autophagy of A549 cells in vivo. Moreover, compound 5e showed good selectivity with no influence on normal vascular endothelial cell growth and the normal chick embryo chorioallantoic membrane (CAM) capillary formation. Therefore, our research provides potential lead compounds for the development of new anticancer drugs against human lung cancer.

The archazolids are potent antiproliferative compounds that have recently emerged as a novel class of promising anticancer agents. Their complex macrolide structures and scarce natural supply make the development of more readily available analogues highly important. Herein, we report the design, synthesis and biological evaluation of four simplified and partially saturated archazolid derivatives. We also reveal important structure-activity relationship data as well as insights into the pharmacophore of these complex polyketides., (© 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

A new series of methyl 2-(2-(4'-[2.2]paracyclophanyl)-hydrazinylidene)-3-substituted-4-oxothiazolidin-5-ylidene)acetates 3a - f were synthesized from the reaction of paracyclophanyl-acylthiosemicarbazides 2a - f with dimethyl acetylenedicarboxylate. Based upon nuclear magnetic resonance (NMR), infrared (IR), and mass spectra (HRMS), the structure of the obtained products was elucidated. X-ray structure analysis was also used as unambiguous tool to elucidate the structure of the products. The target compounds 3a - f were screened against 60 cancer cell lines. They displayed anticancer activity against a leukemia subpanel, namely, RPMI-8226 and SR cell lines. The activity of compound 3a was found as the most cytotoxic potency against 60 cancer cell lines. Consequently, it was selected for further five doses analysis according to National Cancer Institute (NCI) protocol. The cytotoxic effect showed selectivity ratios ranging between 0.63 and 1.28 and between 0.58 and 5.89 at the GI 50 and total growth inhibition (TGI) levels, respectively. Accordingly, compound 3a underwent further mechanistic study against the most sensitive leukemia RPMI-8226 and SR cell lines. It showed antiproliferation with IC50 = 1.61 ± 0.04 and 1.11 ± 0.03 µM against RPMI-8226 and SR cell lines, respectively. It also revealed a remarkable tubulin inhibitory activity, compared to colchicine with IC50 = 4.97 µM/mL. Caspase-3, BAX, and Bcl-2 assays for 3a using annexin V-FITC staining revealed significant pro-apoptotic activity. Furthermore, multidrug-resistant leukemia SR cells were used to show better resistance indices (1.285 ng/mL, 1.15-fold) than the reference. Docking studies with β-tubulin indicate that most of the tested compounds illustrated good binding at the colchicine binding site of the enzyme, especially for compound 3a , which made several interactions better than that of the reference colchicine.

Treatment of inflammation using NSAIDs is coupled with a risk of severe gastric adverse events. Development of dual COX-2/5-LOX inhibitors turns out to be an imperative area devoted to safer NSAIDs. A series of thiourea, thiazole, and thiazolidene derivatives were synthesized by green synthetic approach and COX-1, COX-2 and 5-LOX inhibition screening resulted in the identification of a potent compound 6l with IC 50 of 5.55 µM, 0.09 µM, and 0.38 µM respectively. Compound 6l made significant decrease (60.82%) in the carrageenan-induced edema in male Wistar rats. qRT-PCR analysis and determination of PGE 2 and LTB 4 in the rat paw tissues indicated that this thiazole based dual inhibitor significantly reduced the expression of COX-2 and 5-LOX genes besides the marked reduction in both PGE 2 and LTB 4 levels. The gastric safety profiling revealed an enhanced gastrointestinal safety of the compound 6l on histopathological examination. Molecular docking studies at COX-2 and 5-LOX active sites were consistent with biological studies by significant protein-ligand interaction. Besides, results of in-vitro PGE 2 and LTB 4 studies on RAW 264.7 cells as well as antioxidant studies were parallel to the dual inhibitory activity. The present investigations identify a promising lead having anti-inflammatory potential with an improved gastric safety profile., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest in the publication., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In the present study, we attempted to develop a novel class of compounds active against Pseudomonas aeruginosa (Pa) by exploring the pharmaceutically well exploited enzyme targets. Since, lack of Pa gyrase B crystal structures, Thermus thermophilus gyrase B in complex with novobiocin (1KIJ) was used as template to generate model structure by performing homology modeling. Further the best model was validated and used for high-throughput virtual screening, docking and dynamics simulations using the in-house database for identification of Pa DNA gyrase B inhibitors. This study led to an identification of three lead molecules with IC 50 values in range of 6.25-15.6 µM against Pa gyrase supercoiling assay. Lead-1 optimization and expansion resulted in 15 compounds. Among the synthesized compounds six compounds were shown good enzyme inhibition than Lead-1 (IC 50 6.25 µM). Compound 13 emerged as the most potential compound exhibiting inhibition of Pa gyrase supercoiling with an IC 50 of 2.2 µM; and in-vitro Pa activity with MIC of 8 µg/mL in presence of efflux pump inhibitor; hence could be further developed as novel inhibitor for Pa gyrase B., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The design and synthesis of novel coumarin-thiazolyl ester derivatives of potent DNA gyrase inhibitory activity were the main aims of this study. All the novel synthesized compounds were examined for their antibacterial activity against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salmonella. Compound 8p exhibited excellent antibacterial activity against four bacteria strains with MIC values of 0.05, 0.05, 8, and 0.05 μg/mL, respectively. In vitro drug-resistant bacterial inhibition experiments indicated that compound 8p exhibited the best bacteriostatic effect in the selected compounds and four positive control drugs with MIC values of 4 μg/mL. In vitro enzyme inhibitory assay showed that compound 8p exhibited potent inhibition against DNA gyrase with IC 50 values of 0.13 μM. The molecular docking model indicated that compounds 8p can bind well to the DNA gyrase by interacting with amino acid residues. This study demonstrated that the compound 8p can act as the most potent DNA gyrase inhibitor in the reported series of compounds and provide valuable information for the commercial DNA gyrase inhibiting bactericides., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The M 3 muscarinic acetylcholine receptor (mAChR) is a member of the family of mAChRs, which are associated with a variety of physiological functions including the contraction of various smooth muscle tissues, stimulation of glandular secretion, and regulation of a range of cholinergic processes in the central nerve system. We report here the discovery and a comprehensive structure--activity relationships (SARs) study of novel positive allosteric modulators (PAMs) of the M 3 mAChR through a high throughput screening (HTS) campaign. Compound 9 exhibited potent in vitro PAM activity towards the M 3 mAChR and significant enhancement of muscle contraction in a concentration-dependent manner when applied to isolated smooth muscle strips of rat bladder. Compound 9 also showed excellent subtype selectivity over other subtypes of mAChRs including M 1 , M 2 , and M 4 mAChRs, and moderate selectivity over the M 5 mAChR, indicating that compound 9 is an M 3 -preferring M 3 /M 5 dual PAM. Moreover, compound 9 displayed acceptable pharmacokinetics profiles after oral dosing to rats. These results suggest that compound 9 may be a promising chemical probe for the M 3 mAChR for further investigation of its pharmacological function both in vitro and in vivo., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

By understanding the rampant infections of Mycobacterium tuberculosis (Mtb) and inflammations caused due to the generation of radical species during the Mtb infection, a series of (E)-2-(2-allylidenehydrazinyl)thiazole derivatives, with dual-action properties, was designed. The molecules were designed with a considerable variation in LogP, one of the critical parameters in physicochemical properties, and analyzed for their drug-likeness. For the synthesis, a simple, green, and multicomponent one-pot synthesis method was developed. The in vitro inhibition potentials were evaluated against Mtb H 37 Rv by the microplate Alamar Blue assay. The results reveal that compound 6 was potent, with a MIC value of 6.5 µg/ml, and showed better interactions with the KasA protein with binding free energy (ΔG) of -9.4 kcal/mol. Also, the radical scavenging properties were studied to establish the dual-action properties of the molecules. Compound 9 exhibited promising antioxidant and nitric oxide radical scavenging activities, with 81.7% and 81.0%, respectively, at 1,000-μg/ml concentration., (© 2020 Deutsche Pharmazeutische Gesellschaft.)

Ethyl 2-(3-allylthioureido)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate (1) was used as a building block for synthesis of new heterocycles. Pyrimidine and thiazole moieties were achieved upon condensation of compound 1 with various reagents such as chloroacetic acid, dietyl malonate, ninhydrin, 2,3-epoxy-2,3-dihydro-1,4-naphthoquinone, and hydrazine hydrate. The structures of the newly synthesized compounds were confirmed using spectral measurements. The prepared products were evaluated for their anticancer activity against colon HCT-116 human cancer cell line. Compounds 6, 9, 10a, 11, 12, 15 have displayed potent activity.

Pyridazinone analogues have been known to be potential candidates for anticonvulsant agents. We have identified several pyridazinone-based anticonvulsant agents. As a continuation to our previous research, a series of hybrid pyridazinone-thiazole connected through amide linkage were designed and synthesized. Among these, compound SP-5F demonstrated significant anticonvulsant activity with median effective dose of 24.38 mg/kg (MES) and 88.23 mg/kg (scPTz). Results of GABA estimation showed a marked increase in the GABA level when compared with control. Molecular docking studies at the active site of GABA receptor, further confirmed the GABA modulatory effects of SP-5F., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

A series of novel 2-Amino-4-Methylthiazole analogs were developed via three-step reaction encompassing hydrazine-1-carboximidamide motif to combat Gram-positive and Gram-negative bacterial and fungal infections. Noticeably, the thiazole-carboximidamide derivatives 4a-d displayed excellent antimicrobial activity and the most efficacious analogue 4d with MIC/MBC values of 0.5 and 4 μg/mL, compared to reference drugs with very low toxicity to mammalian cells, resulting in a prominent selectivity more than 100 folds. Microscopic investigation of 4d biphenyl analogue showed cell wall lysis and promote rapid bactericidal activity though disrupting the bacterial membrane. In addition, an interesting in vitro investigation against GlcN-6-P Synthase Inhibition was done which showed potency in the nanomolar range. Meanwhile, this is the first study deploying a biomimicking strategy to design potent thiazole-carboximidamides that targeting GlcN-6-P Synthase as antimicrobial agents. Importantly, Molecular modeling simulation was done for the most active 4d analogue to study the interaction of this analogue which showed good binding propensity to glucosamine binding site which support the in vitro data., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Inc.)

Induction of apoptosis is a common chemotherapeutic mechanism to kill cancer cells The thiazole system has been reported over the past decades as a building block for the preparation of anticancer agents. A novel series of 2-arylalkylamino-4-amino-5-(3',4',5'-trimethoxybenzoyl)-thiazole derivatives designed as dual inhibitors of tubulin and cyclin-dependent kinases (CDKs) were synthesized and evaluated for their antiproliferative activity in vitro against two cancer cell lines and, for selected highly active compounds, for interactions with tubulin and cyclin-dependent kinases and for cell cycle and apoptosis effects. Structure-activity relationships were elucidated for various substituents at the 2-position of the thiazole skeleton. Among the synthesized compounds, the most active analogues were found to be the p -chlorobenzylamino derivative 8e as well as the p -chloro and p -methoxyphenethylamino analogues 8f and 8k , respectively, which inhibited the growth of U-937 and SK-MEL-1 cancer cell lines with IC 50 values ranging from 5.7 to 12.2 μM. On U-937 cells, the tested compounds 8f and 8k induced apoptosis in a time and concentration dependent manner. These two latter molecules did not affect tubulin polymerization (IC 50 > 20 μM) nor CDK activity at a single concentration of 10 μM, suggesting alternative targets than tubulin and CDK for the compounds.