Cinnamyl derivatives: synthesis and factor Xa (FXa) inhibitory activities

To develop a potent and oral anticoagulant, a series of compounds with cinnamyl moiety was synthesized and their factor Xa (FXa) inhibitory activities were examined. As a result, some cinnamyl derivatives showed potent FXa inhibitory activities in vitro. Among them, compounds with substituent at the 3-position on the central benzene ring represented by (N-{4-[1-(acetimidoyl)piperidin-4-yloxy]-3-chlorophenyl}-N-[(E)-3-(3-amidinophenyl)-2-propenyl]sulfamoyl)acetic acid dihydrochloride (45b) and (N-{4-[1-(acetimidoyl)piperidin-4-yloxy]-3-carbamoylphenyl}-N-[(E)-3-(3-amidinophenyl)-2-propenyl]sulfamoyl)acetic acid dihydrochloride (45j) exhibited potent FXa inhibitory activities with IC(50) values of less than 10 nM in vitro. These compounds also showed potent anticoagulant activities both in vitro and ex vivo. Furthermore, these compounds exhibited no lethal toxicity (30 mg/kg, i.v.).     

Indoline derivatives II: synthesis and factor Xa (FXa) inhibitory activities

Factor Xa (FXa) is well known to play a pivotal role in blood coagulation, so FXa inhibitor is a promising drug candidate for prophylaxis and treatment of thromboembolic diseases. In the course of our research, we have found that (R)-5-[1-(acetimidoyl)piperidin-4-yloxy]-2-(7-amidinonaphthalen-2-yl)-1-(ethanesulfonyl)indoline ((R)-1) showed potent FXa inhibitory activity in vitro. However, single oral administation (RS)-1 showed high toxicity in mice. Among newly synthesized compounds, ({(RS)-5-[1-(acetimidoyl)piperidin-4-yloxy]-2-(7-amidinonaphthalen-2-yl)indolin-1-yl}sulfonyl)acetic acid ((RS)-11d) showed more potent FXa inhibitory activity and higher safety than (RS)-1. The R-isoform of compound 11d ((R)-11d) exhibited potent in vitro anticoagulant activity in human and hamster plasma. Orally administered (R)-11d also showed dose-dependent potent anticoagulant activity in hamsters, marmosets and cynomolgus monkeys. Compound (R)-11d with potent anticoagulant activity and high safety is therefore favorable as a novel oral FXa inhibitor.     

Indoline derivatives I: synthesis and factor Xa (FXa) inhibitory activities

A series of bisamidine derivatives each having a ring structure in the center of the molecule was synthesized and their Factor Xa (FXa) inhibitory activities were evaluated. Among them, some indoline derivatives showed potent inhibitory activities in vitro. In particular, (R)-18a having an (R)-configuration at the 2-position of the indoline ring exhibited the most potent FXa inhibitory activity in vitro, more potent than DX-9065a. Furthermore, (R)-18a exhibited more potent anticoagulant activity than DX-9065a. We also succeeded in obtaining an X-ray crystal structure of FXa bound with (R)-18a.     

Design, synthesis and inhibitory activities of 8-(substituted styrol-formamido)phenyl-xanthine derivatives on monoamine oxidase B

The design and synthesis of two series of 8-(substituted styrol-formamido)phenyl-xanthine derivatives are described. Their in vitro monoamine oxidase B (MAO-B) inhibition were tested and the effect of substituents on the N-7, phenyl and the substituted positions are discussed. It was observed that compound 9b displayed significant MAO-B inhibition activity and selectivity, fluorine substitution plays a key role in the selectivity of MAO-B inhibition, and the styrol-formamido group at position-3' may enhance the activity and selectivity of 8-phenyl-xanthine analogues. These results suggest that such compounds may be utilized for the development of new candidate MAO-B inhibitors for treatment of Parkinson's disease.     

Synthesis and pancreatic lipase inhibitory activities of some 1,2,4-triazol-5(3)-one derivatives

In this study, starting from 4-amino-5-(4-chlorobenzyl)-2,4-dihydro-3H-1,2,4-triazole-3-one ( 1 ), the 4-Amino-5-(4-chlorobenzyl)-2-undecyl-2,4-dihydro-3H-1,2,4-triazol-3-one ( 2 ) was first synthesized and this compound was converted to Schiff base derivatives ( 3a-e ). In the second step of the study, the 2-[3-(4-chlorobenzyl)-5-oxo-1-undecyl-1,5-dihydro-4H-1,2,4-triazole-4-yl]-acetohydrazide ( 6 ), which was used as a key product in the synthesis of many heterocyclic compounds was synthesized in four steps, and then this compound was converted into methylidene acetohydrazide ( 7a-e ), thiosemicarbazide ( 8a-e ), and 1,2,4-triazole-5-thione ( 9a-e ) derivatives. Also, in the last part of the study, 1,2,4-triazole-5-thione derivatives were changed into Mannich bases ( 10a-b ) bearing a 4-phenylpiperazine ring. These new compounds were tested with regard to pancreatic lipase (PL) inhibition activity, and compound 3b , 3d , 7d , 8d , and 9d showed a considerable anti-lipase activity at various concentrations. The activity of compounds 7b (IC₅₀ = 1.45 ± 0.12 μM) was the highest in terms of IC₅₀, comparable to that of orlistat, a well-known PL inhibitor used as an antiobesity drug.     

Triphenylarsenic(V) and -antimony(V) derivatives of multidentate Schiff bases: synthesis,characterization, and antimicrobial activities

Equimolar reactions of Ph _n M(OPr ⁱ )₂ (where M?=?As and Sb) with Schiff bases [OHC₆H₄CH=N(R)OH] in benzene solution yield organoarsenic and -antimony derivatives, (where M?=?As and Sb; n?=?1 and 3; R?=?–CH₂CH(CH₃)–, –(CH₂)₃–, –(CH₂)₂–, and –C(CH₃)₂CH₂–). All these derivatives have been characterized by elemental analyses and molecular weight measurements, and structures have been proposed on the basis of IR, NMR (¹H and ¹³C), and FAB-mass studies. Schiff bases and their corresponding organoantimony derivatives have been screened for antimicrobial activity against Aspergillus flavus (fungus) and Escherichia coli (bacteria).     

Conduramine F-1 epoxides: synthesis and their glycosidase inhibitory activities

Starting from (±)-7-oxanorbornenone ((±)-14), (±)-(1RS,2RS,3SR,6SR)-6-azidocyclohex-4-en-1,2,3-triol ((±)-24) and (±)-(1RS,2RS,3SR,6RS)-6-azidocyclohex-4-en-1,2,3-triol ((±)-26) were obtained. Epoxidation of the latter cyclohexene derivative gave two epoxides (±)-30 and (±)-31 that were converted into (±)-conduramine F-1 epoxides (±)-10 and (±)-11 and N-substituted derivatives (±)-12 and (±)-13. Compound (±)-(1RS,2SR,3RS,4SR,5RS,6SR)-5-({[4-(trifluoromethyl)phenyl]methyl}amino)-7-oxabicyclo[4.1.0]heptane-2,3,4-triol ((±)-12c) is a good, non-competitive inhibitor of β-xylosidase from Aspergillus niger (K_i=2.2 μM), and (±)-(1RS,2RS,3SR,4RS,5SR,6SR)-5-{[(biphenyl-4-yl)methyl]amino}-7-oxabicyclo[4.1.0]heptane-2,3,4-triol ((±)-13d) is a good inhibitor of α-glucosidase from brewer's yeast (K_i=2.8 μM, non-competitive).     

New angular oxazole-fused coumarin derivatives: synthesis and biological activities

Twelve angular oxazole-fused coumarin derivatives were designed, synthesised and characterised by ¹H NMR, ¹³C NMR and HRMS. The structure of compound 4a was further confirmed by X-ray single-crystal diffraction. The bioassay experiment results indicated that compounds 4f and 4l have high antifungal activity on the mycelium growth of 4 plant disease fungi. Especially, compound 4l has a stronger antifungal activity compare to the commercial fungicide, Carbendazim. The herbicidal activity experiment showed that 4a and 4b can significantly inhibit the taproot and caulis development of Chenopodium album seedling and have better activities than the commercial herbicide, Acetochlor.     

Synthesis and evaluation of 1-arylsulfonyl-3-piperazinone derivatives as a factor Xa inhibitor II. Substituent effect on biological activities

Intravascular clot formation is an important event in a number of cardiovascular diseases. The prevention of blood coagulation has become a major target for new therapeutic agents. Factor Xa (FXa) is a trypsin-like serine protease that plays a key role in the blood coagulation cascade and represents an attractive target for anticoagulant drug development. We have investigated substituents in the central part of a lead compound (3: M55113), and discovered that compound M55551 (34: (R)-4-[(6-Chloro-2-naphthalenyl)sulfonyl]-6-oxo-1-[[1-(4-pyridinyl)-4-piperidinyl]methyl]-2-piperazinecarboxylic acid) is a potent inhibitor of FXa (IC(50)=0.006 microM), with high selectivity for FXa over trypsin and thrombin. The activity of this compound is ten times more powerful than the lead compound.     

Synthesis and evaluation of 1-arylsulfonyl-3-piperazinone derivatives as factor Xa inhibitor

Intravascular clot formation is an important factor in a number of cardiovascular diseases. Therefore, the prevention of blood coagulation has become a major target for new therapeutic agents. One attractive approach is the inhibition of factor Xa (FXa), which is a key enzyme in coagulation cascade responsible for the generation of thrombin by limited proteolysis of its zymogen, prothrombin. We have investigated 1-arylsulfonyl-3-piperazinone derivatives, containing a 4-(piperidino)pyridine group in place of guanidino and/or amidino groups, and discovered compound M55113 (30a: 4-[(6-Chloro-2-naphthalenyl)sulfonyl]-1-[[1-(4-pyridinyl)-4-piperidinyl]methyl]piperazinone), as a potent inhibitor of FXa (IC50=0.06 microM) with high selectivity for FXa over trypsin and thrombin.     

Oxovanadium phenanthroimidazole derivatives: synthesis,DNA binding and antitumor activities

Four unsymmetrical oxovanadium phenanthroimidazole complexes, [VO(hntdtsc)(NPIP)] (1), [VO(hntdtsc)(CPIP)] (2), [VO(hntdtsc)(MEPIP)] (3) and [VO(hntdtsc)(HPIP)] (4) (hntdtsc = 2-hydroxy-1-naphthaldehyde thiosemicarbazone, NPIP = 2-(4-nitrophenyl)-imidazo[4,5-f]1,10-phenanthroline, CPIP = 2-(4-chlorphenyl)-imidazo[4,5-f]1,10-phenanthroline), MEPIP = 2-(4-methylphenyl)-imidazo[4,5-f]1,10-phenanthroline), HPIP = 2-(4-hydroxylphenyl)-imidazo[4,5-f] 1,10-phenanthroline), have been synthesized and characterized. Their DNA binding and antitumor activities were determined by biochemical methods. All four oxovanadium complexes can bind with CT-DNA by an intercalation model and can also cleave supercoiled plasmid DNA in the presence of H₂O₂. The antitumor properties and mechanism of the complexes have been analyzed by MTT assay, cell cycle analysis, apoptosis assay and Western blot analysis. The results showed that the free ligands and their corresponding complexes all possess antiproliferative activities with very low IC₅₀ values against Hela, BIU-87 and SPC-A-1 cell lines. Complex 1, which has a strongly electron-withdrawing nitro group, exhibited the best antiproliferative activities. Complex 1 caused G₀/G₁ phase arrest of the cell cycle and induced apoptosis in Hela cells. Additionally, complex 1 attenuated the phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2).This indicates that inhibition of the ERK1/2 signaling pathway may contribute to the antitumor effects of these complexes.     

One-pot synthesis of new hydantoin (thiohydantoin) derivatives and evaluation of their antibacterial and antioxidant activities

One-pot four-component reactions of phenacyl bromides, parabanic or thioparabanic acids, thiophenols, and triphenylphosphine in the presence of triethylamine afforded new derivatives of hydantoin or thiohydantoin in good to high yields (65%-90%). Their antibacterial activities were evaluated against two Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Among the synthesized compounds, the obtained products from 2-hydroxythiophenol exhibited higher antibacterial activity than those obtained from 2-aminothiophenol. Compound 9l including N,N′^′-diphenyl thiohydantoin moiety showed the highest antibacterial activity (26.0 ± 01.4) against B subtilis, in comparison with other synthesized samples. The antioxidant activities of the synthesized hydantoins and thiohydantoins were investigated by DPPH radical-scavenging based on Blois method. The results showed that all the compounds have high DPPH inhibition potency (77.4%-83.9%) that it could be due to existence of heteroatoms with lone pair electrons and exchangeable protons on their NH₂ and OH groups.     

Synthesis and iNOS/nNOS inhibitory activities of new benzoylpyrazoline derivatives

A series of new Δ²-pyrazoline derivatives has been synthesized by means of a 1,3-dipolar-cycloaddition reaction. Ethyl 3-(5-methoxy-2-nitrobenzoyl)-Δ²-pyrazoline-5-carboxylate (5a) has been designed for the formation of the benzoylpyrazoline system present in these derivatives. Two synthetic routes have been utilized changing the starting products in the cycloaddition reaction. In both routes, the majority product obtained was only a Δ²-pyrazoline. The intermediate ethyl 1-acyl-3-(2-nitrobenzoyl-5-substituted)-Δ²-pyrazoline-5-carboxylate derivatives have been transformed into the final compounds by means of several chemical treatments. The compounds have been biologically evaluated as inhibitors of nitric oxide synthase (NOS), showing better affinity towards the inducible NOS isoform than versus neuronal NOS.     

三嗪噁二唑基吡唑衍生物抑酶活性的QSAR模型

基于拓扑化学理论,原子类型电拓扑态指数(Mk)被用于表征18种三嗪噁二唑基吡唑衍生物的化学微环境。采用最佳变量子集回归方法,分别建立上述化合物对蛋白酪氨酸磷酸酯酶1B(PTP1B)、细胞分裂周期25磷酸酯酶B(Cdc25B)的抑酶活性(P_t、C_d)与Mk的定量构效关系(QSAR)模型。它们的最佳三元QSAR模型的判定系数(R~2)依次为0.896、0.828,逐一剔除法交叉验证相关系数(R_(cv)~2)依次为0.830、0.688。经R_(cv)~2、VIF、FT、AC等检验,该模型具有良好的稳健性及预测能力。经训练集验证,上述模型均具有良好的外部预测能力。模型显示,影响Pt、Cd的因素既有不同的结构基团(-CH_3、-O-、-NH_2和芳环中-N=),也有相同的因素(芳环中-C=)。     

Asymmetric synthesis of functionalized piperidine derivatives: synthesis of (S)-anatabine

A short and efficient chiral synthesis of 6-aryl-5-phenylsulfonyl-1,2,5,6-tetrahydropyridines was achieved in moderate yield and with good selectivity. The absolute configurations were assigned by extending the methodology to (S)-anatabine and as well with NMR experiments.     

Synthesis and platelet aggregation inhibitory activities of 3-(2-oxopropylidene)azetidin-2-one derivatives. II.

A series of 3-acylidene-4-methylazetidin-2-one derivatives bearing various substituents at the 1-position of the azetidin-2-one ring was synthesized. These compounds were evaluated for platelet aggregation inhibitory activities. Most of the compounds synthesized showed potent inhibitory activities against rabbit platelet aggregation induced by adenosine diphosphate or collagen in vitro. Structure-activity relationships are also discussed.     

Total synthesis and antidepressant activities of laetispicine and its derivatives

The first total synthesis of laetispicine (1a), an amide alkaloid isolated from the stems of Piper laetispicum C.DC (Piperaceae), and the synthesis of some of its derivatives were described. Based on the evaluation of antidepressant activities in the forced swimming test, compounds 1h and 1i were identified as potent and safe antidepressant lead compounds.     

Synthesis and anticonvulsant activities of (R)-(O)-methylserine derivatives

Efficient procedures for the synthesis of (R)-N-benzyl-2-amino-3-methoxypropionamide ((R)-3), 2-acetamido-3-methoxypropionic acid (4), and O-methylserine (5) are described beginning from (R)-Cbz-serine ((R)-7). The reactions proceeded with little or no racemization and permitted the synthesis of the potent anticonvulsant (R)-N-benzyl-2-acetamido-3-methoxypropionamide ((R)-2). The anticonvulsant activities of 2–4 were determined revealing the surprising activity of (R)-2.     

Solvent-free synthesis,x-ray studies and in vitro inhibitory activities of copper(II) complexes of non-steroidal anti-inflammatory drugs

Solid-state mechanochemical synthesis of [Cu(CAF)₂(H₂O)(OAc)]OAc complex 1a and [Cu(COD)₂(H₂O)(OAc)]OAc complex 2a were obtained by grinding stoichiometric amounts of Cu(CH₃COO)₂·H₂O and corresponding non-steroidal anti-inflammatory drugs[(caffeine (CAF) and codeine(COD)], respectively, in a mortar with pestle. Solvent-based synthesis of 1b and 2b was also carried out by reaction of metal acetate salt and each drug by refluxing at 70 °C in CH₃OH for 1 h for comparison purposes. The complexes 1a and 2a were characterized by comparison of elemental analysis, FT-IR, UV–Vis and ¹H NMR spectra with those of the free ligand and solvent-based products (1b and 2b). The analytical and spectroscopic data of the complexes prepared via the two different methods are almost identical. X-ray diffraction patterns of the complexes prepared by mechanochemical method were different from that of the starting material suggesting formation of new metal complexes. In vitro inhibitory activities of both mechanochemical and solvent-based complexes were found to be higher than parent ligands, indicating that the antimicrobial effect of these drugs could be enhanced when they are chelated to the metal. The mechanochemical synthesis was carried out without the use of solvent or external heating. The method is faster and gives a higher yield than corresponding solvent-based reactions. The solid state reaction presented higher efficiency in terms of materials, energy and time compared to solvent-based synthesis.     

白杨素衍生物的合成及生理活性研究进展

黄酮类化合物白杨素具有抗氧化、抗肿瘤、抗癌、抗病毒、抗高血压、抗糖尿病、抗菌、抗过敏等广泛的生理活性.近年来,许多国内外学者对其衍生物的合成及生理活性进行了研究,以期开发出活性更高,更具有临床应用价值的药物.本文着重对各类白杨素衍生物的合成及生理活性研究进展进行综述.