Discovery of N-benzyl hydroxypyridone carboxamides as a novel and potent antiviral chemotype against human cytomegalovirus (HCMV)

Current drugs for treating human cytomegalovirus(HCMV)infections are limited by resistance and treatment-associated toxicities.In developing mechanistically novel HCMV antivirals,we discovered an N-benzyl hydroxypyridone carboxamide antiviral hit(8a)inhibiting HCMV in submicromolar range.We describe herein the structure–activity relationship(SAR)for 8a,and the characterization of potent analogs for cytotoxicity/cytostatic property,the preliminary mechanism of action,and the absorption,distribution,metabolism and excretion(ADME)properties.The SAR revealed a few pharmacophore features conferring optimal antiviral profile,including the 5-OH,the N-1 benzyl,at least one–CH_(2)−in the linker,and a di-halogen substituted phenyl ring in the amide moiety.In the end,we identified numerous analogs with sub-micromolar antiviral potency and good selectivity index.The preliminary mechanism of action characterization used a pUL89-C biochemical endonuclease assay,a virus entry assay,a time-of-addition assay,and a compound withdrawal assay.ADME profiling measuring aqueous solubility,plasma and liver microsomal stability,and parallel artificial membrane permeability assay(PAMPA)permeability demonstrated largely favorable drug-like properties.Together,these studies validate the N-benzyl hydroxypyridone carboxamide as a viable chemotype for potent and mechanistically distinct antivirals against HCMV.

Microwave Assistant Synthesis and Crystal Structures of Two Substituted Oxazole Isoxazole Carboxamides

Two novel substituted phenyl oxazole isoxazole carboxamides have been synthesized by microwave assistant technology.The target compounds were characterized by IR,1H NMR,13C NMR and HRMS,and their single-crystal structures were further determined by X-ray diffraction.3-Phenyl-4-(2΄-methyl-2΄-isopropyl-1΄,3΄-oxazole)-5-methyl isoxazole carboxamide(6a)crystallizes in monoclinic system,space group P21/c with a=6.2137(12),b=19.923(4),c=13.748(3)Å,β=92.30(3)°,V=1700.6(6)Å3,Dc=1.228 Mg/m3,Z=4,F(000)=672,μ(MoKα)=0.084 mm-1,R=0.0526 and wR=0.1259.3-(2΄-Fluoro-6΄-chloro-phenyl)-4-(2΄-methyl-2΄-ethyl-1΄,3΄-oxazole)-5-methyl isoxazole carboxamide(6b)crystallizes in triclinic system,space group P with a=7.8750(16),b=10.596(2),c=11.725(12)Å,β=102.05(3)°,V=859.5(3)Å3,Dc=1.363 Mg/m3,Z=2,F(000)=368,μ(MoKα)=0.250 mm-1,R=0.0738 and wR=0.1941.Both of the molecules prefer to form crystal packing through C–H…O hydrogen bonds.Compounds 6a and 6b show safener activity on maize against the injury of chlorsulfuron.

Synthesis and Evaluation of Antituberculosis Activity of Substituted 2,7-Dimethylimidazo [1,2-a]Pyridine-3-Carboxamide Derivatives

A series of substituted 2,7-dimethylimidazo[1,2-a]pyridine-3-carboxamides derivatives 5a-5m were synthesized through multi-step reactions. To achieve the synthesis of the desired compounds monobromo and dibromo substituted 2-amino-γ-picoline was reacted with ethyl 2-chloroacetoacetate. The crude ethyl ester subjected to hydrolysis in presence of lithium hydroxide to get 2a and 2b, with imidazo[1,2-a]pyri- dine-3-carboxylic acid to get 3a-3b, on treatment with substituted amines 4a-4g to get desired product 5a-5m in presence of EDCI and HOBt. The substituted imidazo[1,2-a]pyridine-3-carboxamides are characterized by FTIR, 1H-NMR, 13C-NMR and mass spectra. These newly synthesized compounds were tested in vitro for their antimycobacterial activity. The preliminary results of antituberculosis study showed that most of the synthesized compounds 5a-5m demonstrated moderate to good antituberculosis activity. Among the tested compounds 5b, 5d and 5e were found to be the most active with minimum inhibitory concentration (MIC) of 12.5 μg/mL against Mycobacterium tuberculosis (H37 RV strain) ATCC No-27294.

Synthesis and Crystal Structure of N-(1,3,4-Thiadiazol-2-yl)-1-[1-(6-chloropyridin-3-yl)methy]-5-methyl-1H-[1,2,3]triazol-4-carboxamide

The crystal structure of the title compound （C12H10ClN7OS, Mr= 335.78） has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group Pi with a = 8.4093（11）, b = 9.4430（12）, c = 11.1454（14） A, α = 95.508（2）, β = 111.366（2）, γ = 115.259（2）°, V = 711.42（16） A3, Z = 2, Dc = 1.568 g/cm3, F（000） = 344, μ（MoKα） = 0.428 mm-1, the final R = 0.0476 and wR = 0.1243 for 2353 observed reflections （I 〉 2o（/））. The dihedral angles between the pyridine and triazole, thiazole and triazole, and pyridine and thiazole rings are 69.2（1）, 9.2（1） and 72.7（1）°, respectively. Intramolecular C（8）--H（8B）...O（1） and N（5）-H（5A）..-N（4） as well as intermolecular C（5）-H（5）...S（1）, C（3）-H（3）.,.N（6） and N（5）-H（5A）...N（1） hydrogen bonds together with weak C-H...Ir hydrogen-bonding and π-π stacking interactions contribute to the stability of the structure. There is also evidence for significant electron delocalization in the triazolyl system.

Synthesis and Crystal Structure of N-(Biphenyl-2-thiocarbamoyl)-4-(1,3-dichlorophenyl) Carboxamide

The synthesis of the title molecule was achieved by the reaction of 2,4-dichloro- benzoyl chloride with potassium thiocyanate in 1：1 molar ratio in dry acetonitrile to afford the corresponding isothiocyante in situ followed by the treatment with 2-aminobiphenyl. The structure of the target compound was established by elemental analysis, FTIR, 1H, 13C NMR and mass spectroscopy and unequivocally confirmed by the crystallographic data. The title compound crystallizes in the monoclinic space group P21/n with a = 13.356（2）, b = 7.0761（11）, c = 20.539（3） A, β = 105.723（4）°, V= 1868.5（5） A3 and Z = 4.

Docking of Glycokinase with Oxo, Sulfo, and Seleno Derivatives of the Carboxamide Activator S41

Inactivation of Glucokinase (GK) is associated with diabetes. Therefore, design of drugs targeting the GK activator site is currently integrated in the?strategy of the diabetes treatment.?The present work investigated the affinity of 30 ligands to GK based on molecular docking using the Gold 5.6 program. Glucokinase’s structure was derived from the Protein Data Bank (PDB Code?3S41), while the ligands were seleno, sulfo and oxo derivatives of the co-crystallized?carboxamide activator (PDB code:?S41). The results of the ligand-protein docking?revealed that GK formed thermodynamically stable complexes with all ligands. The main forces stabilizing the complexes are lipophilic interactions, enhanced by hydrogen bonds. Ligand molecular areas responsible for lipophilic and hydrogen bonding contacts with amino acid residues in the allosteric site of GK were evidenced by molecular electrostatic potentials (MEPs). Interestingly,?twelve of the S41 derivatives interacted with GK more strongly than the co-crystallized activator, while maintaining the lipophilic contacts with key amino acid residues like Arg63, which are catalytically crucial for?therapeutic properties of GK activators (GKAs).?It is noteworthy that divalent Se and S atoms were also involved in chalcogen bonds in the GKA site. Those bonds were nearly linear like hydrogen bonds. Such bond directionality should guide the design of pharmacophoric ligands containing chalcogen atoms.

Structure-based drug discovery of novel fusedpyrazolone carboxamide derivatives as potent and selective AXL inhibitors

a novel and promising antitumor target,AXL plays an important role in tumor growth,metastasis,immunosuppression and drug resistance of various malignancies,which has attracted extensive research interest in recent years.In this study,by employing the structure-based drug design and bioisosterism strategies,we designed and synthesized in total 54 novel AXL inhibitors featuring a fusedpyrazolone carboxamide scaffold,of which up to 20 compounds exhibited excellent AXL kinase and BaF3/TEL-AXL cell viability inhibitions.Notably,compound 59 showed a desirable AXL kinase inhibitory activity(IC_(50):3.5 nmol/L)as well as good kinase selectivity,and it effectively blocked the cellular AXL signaling.In turn,compound 59 could potently inhibit BaF3/TEL-AXL cell viability(IC_(50):1.5 nmol/L)and significantly suppress GAS6/AXL-mediated cancer cell invasion,migration and wound healing at the nanomolar level.More importantly,compound 59 oral administration showed good pharmacokinetic profile and in vivo antitumor efficiency,in which we observed significant AXL phosphorylation suppression,and its antitumor efficacy at 20 mg/kg(qd)was comparable to that of BGB324 at 50 mg/kg(bid),the most advanced AXL inhibitor.Taken together,this work provided a valuable lead compound as a potential AXL inhibitor for the further antitumor drug development.

Synthesis and in vivo nematocidal evaluation of novel 3-（trifluoromethyl）-lH-pyrazole-4-carboxamide derivatives

Pyrazole carboxamide derivatives represent an important class of fungicides in agrochemicals. To find more novel structural pyrazole carboxamides, a novel series of 3-（trifluoromethyl）-lH-pyrazole-4-carboxamide compounds were prepared from ethyl 4,4,4-trifluoroace- toacetate and triethyl orthoformate as starting materials. All the products were characterized by Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance （NMR）, 13C NMR, 19F NMR and mass spectrography. The bioassay results showed these fluorine-containing pyrazole carboxamides have a weak fungicidal activity but some of them exhibit a good nematocidal activity against M. incognita.

Synthesis,biological activities and 3D-QSAR studies of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety

A series of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety were synthesized and characterized on the basis of NMR and elemental analysis(EA). The crystal structure of(R)-N-(2-methyl-1-(methylthio)propan-2-yl)-2-(4-nitrophenyl)-4,5-dihydrothiazole-4-carboxamide(13 d) was determined to show R configuration. The bioasssy results indicated that most title compounds displayed good and broad spectrum antifungal activities against several phytopathogenic fungi. The structure activity relationships were discussed. Based on the antifungal activity of title compounds against Phytophthora capsici, a CoMSIA calculation was performed to establish a 3 D-QSAR model, which revealed that electrostatic and hydrophobic fields were the two most significant factors for antifungal activity. According to the established 3D-QSAR model, structure optimization was carried out to find(R)-N-((R)-1-(methylthio)propan-2-yl)-2-(p-tolyl)-4,5-dihydrothiazole-4-carboxamide(15 h)with excellent activity against Phytophthora capsici, thus emerging as a new lead compound for novel antiphytopathogenic fungus agent development.

Characterization of inthomycin biosynthetic gene cluster revealing new insights into carboxamide formation

Inthomycins are polyketide antibiotics which contain a terminal carboxamide group and a triene chain. Inthomycin B(1) and its two new analogues 2 and 3 were isolated from the crude extract of Streptomyces pactum L8. Identification of the gene cluster for inthomycin biosynthesis as well as the ^(15)N-labeled glycine incorporation into inthomycins are described. Combined with the gene deletion of the rare P450 domain in the NRPS module, a formation mechanism of carboxamide moiety in inthomycins was proposed via an oxidative release of the assembly chain assisted by the P450 domain.

Synthesis and biological evaluation of novel pyrazole carboxamide with diarylamine-modified scaffold as potent antifungal agents

Twenty-seven novel pyrazole carboxamides with diarylamine-modified scaffold were designed,synthesized and characterized in detail via1 H NMR,^（13） C NMR, IR and ESI-HRMS. Preliminary bioassays showed that some of the target compounds exhibited good antifungal activity against Rhizoctonia solani,Rhizoctonia cerealis and Sclerotinia sclerotiorum. Among them, compound 9c-7 exhibited the highest antifungal activities against R. solani, R. cerealis and S. sclerotiorum in vitro with IC_（50） values of 0.013, 1.608 and 1.874 mg/m L, respectively. Notably, compound 9c-7 still presented the highest fungicidal activities against R. solani in vivo with an IC_（50） value of 22.21 mg/m L. Molecular docking simulation results reveal that compound 9c-7 binds well to the hydrophobic pockets of the receptor protein succinate dehydrogenase. This study suggests that compound 9c-7 could act as a potential fungicide to be used for further optimization.

Design,synthesis and insecticidal activities of novel anthranilic diamides containing polyfluoroalkyl pyrazole moiety

In order to discover new molecules with good insecticidal activities, a series of anthranilic diamides containing polyfluoroalkyl pyrazole were designed and synthesized, and their structures were characterized by1 H NMR and HRMS. Bioassays demonstrated that some of the title compound exhibited excellent insecticidal activities. The larvicidal activities of compound 8a, 8c, 8g, 8k and 8l against Mythimna separata Walker were 100% at 0.8 mg/L. The insecticidal activities of compound 8a, 8c,8e, 8g, 8k and 8l against Plutella xylostella Linnaeus were 100% at 0.4 mg/L. Surprisingly compounds 8a and 8c still showed 100% larvicidal activities against Plutella xylostella Linnaeus at 0.08 mg/L comparable to the commercialized Chlorantraniliprole. The LC_（50） of compound 8a and 8c against M. separata is 0.048 and 0.043 mg/L respectively.

Molecular Modeling Studies of 4-Hydroxyamino α-Pyranone Carboxamide Analogues as Hepatitis C Virus Inhibitor Using 3D-QSAR and Molecular Docking

In this paper, 42 4-hydroxyamino α-pyranone carboxamide analogues as Hepatitis C Virus(HCV) inhibitor 3 D-QSAR model was built based on Topomer CoMFA. The non-cross-validation(r2), cross-validation(q2), correlation coefficient of external validation(Q ext2), non-cross validated standard error(SD), standard error of prediction(SDCV) and F are 0.909, 0.615, 0.967, 0.13, 0.28 and 37.287, respectively. The obtained Topomer CoMFA model has good estimation stability and prediction capability. Topomer Search was employed as a tool for virtual screening in lead-like compounds in the ZINC database. Then, 6 R1 groups and 4 R2 groups with higher contribution values were employed to alternately substitute for the R1 and R2 of the template compound 21 with the highest bioactivity. As a result, 22 new molecules with higher activity than that of the template molecule were designed successfully. The Topomer Search technology could be effectively applied to screen and design new 4-hydroxyamino α-pyranone carboxamide analogues. The molecular docking method was also used to study the interactions of these drugs by docking the ligands into HCV active site, which revealed the likely bioactive conformations. This study showed extensive interactions between the 4-hydroxyamino α-pyranone carboxamide analogues and the active sites of HCV(residues TYR466, GLN384, TYR383 and ASP335). The design of potent new inhibitors of HCV can get useful insights from these results.

Synthesis and biological evaluation of ^(99m)Tc-HEDTA/HYNIC-MPP4 complex for 5-HT_(1A) receptor imaging

5-HT_(1A)receptor is associated with a variety of pathophysiology of neuropsychiatric disorders.Accordingly,we have synthesized a new 5-HT_(1A) receptor ligand(HYNIC-MPP4)and labeled it with^(99m)Tc using N-(2-hydroxyethyl)ethylenediaminetriacetic acid(HEDTA)as coligand.^(99m)Tc-HEDTA/HYNIC-MPP4 was prepared under pH 6 at room temperature.Biodistribution of^(99m)Tc-HEDTA/HYNIC-MPP4 in normal mice showed that this complex had moderate brain uptake(0.60%ID·g^(-1)at 2 min p.i.)and good retention.The hippocampus had the highest radioactivity uptake at 2 min p.i.(1.84%ID·g^(-1)).The ratio of Hipp/CB was 3.1 at 2 min p.i.and increased to 4.4 at 60 min p.i.After blocking with 8-hydroxy-2-(dipropylamino)tetralin,the uptake of hippocampus was decreased significantly from 1.84%ID·g^(-1) to 0.53%ID·g^(-1) at 2 min p.i.,while the cerebellum had no significant decrease.This^(99m)Tc complex could be a potent agent for 5-HT_(1A) receptor imaging.

Synthesis,Crystal Structure and Anti-fungal/Anti-oomycete Activity of New Pyrazole-benzene Carboxamide Derivatives

Four novel pyrazole-benzene carboxamide derivatives 2a~2d were synthesized and characterized by NMR,HRMS spectral method and X-ray diffraction analysis,and were further conducted for screening the anti-fungal/anti-oomycete activity.Compound 2d crystallizes as monoclinic space group P21/c with a=42.260(4),b=5.3751(4),c=8.0129(9)Å,β=92.958(10)°,V=1817.7(3)Å3,Z=4,Mr=385.41,Dc=1.408 Mg/m3,S=1.087,m=0.773 mm-1,F(000)=808,the final R=0.0763 and wR=0.2136 for 2657 observed reflections(I>2σ(I)).The preliminary antifungal assay indicates that the title compounds show fair to excellent antifungal/anti-oomycete activity toward four plant fungi and two crop oomycetes.Among them,compound 2b exhibits the strongest in vitro anti-B.cinerea effects(EC50=1.61 mg/L).In vivo test presents compound 2b displays considerable protective and curative effects to tomato fruits infected by B.cinerea.These results indicate that compound 2b would be potential fungicides leads for further development.

Synthesis and biological evaluation of piperidyl benzimidazole carboxamide derivatives as potent PARP-1 inhibitors and antitumor agents

We have synthesized a series of compounds based on a piperidyl benzimidazole carboxamide structure,and tested their PARP-1 inhibitory activity,as well as cellular inhibitory activity.Some of them show great potency as PARP-1 inhibitors and antitumor activity,which are valuable for further research.In addition,the predicted ADME properties and proposed binding mode with PARP-1 of the compounds were obtained via computational simulation.

Synthesis,Crystal Structure and Antifungal Activity of New Furan-1,3,4-oxadiazole Carboxamide Derivatives

A series of novel furan-1,3,4-oxadiazole carboxamide derivatives (5a~5e) were designed,synthesized and characterized by spectroscopic methods including HR-MS,^(1)H-and ^(13)C-NMR.The crystal structure of compound 5a was determined by single-crystal X-ray diffraction.The compound crystallizes in the triclinic system,space group P■ with a=4.7261(5),b=10.4672(11),c=14.5886(13)?,α=106.081(4)°,β=91.043(3)°,γ=99.456(4)°,Z=2,V=682.48(12)?^(3),M_(r)=348.16,D_(c)=1.694 Mg/m^(3),S=1.008,m=3.025 mm^(-1),F(000)=348,the final R=0.0775 and w R=0.2080 for 2774 observed reflections (I (29) 2σ(I)).There are two kinds of hydrogen bonds (N(3)–H(3A)×××N(2) and C(8)–H(8A)×××O(3)) present in its crystal structure.The preliminary antifungal assay showed that compounds 5b and 5c exhibited significant antifungal activities against several plant pathogenic fungi.