To obtain higher potency and specificity, a series of 7-alkoxy analogues of illudalic acid was synthesized on the base of structure-activity relationship (SAR). All of these compounds exhibited submicromolar inhibition of the enzyme when tested against human leukocyte common antigen-related phosphatase (LAR) (for example, for 15e, IC50 = 180 nmol x L(-1)). They represent the most potent small-molecule inhibitors of LAR so far. These analogues also display excellent selectivity for LAR over other protein tyrosine phosphatases (PTPs) except for the highly homologous PTPsigma. The compound 15f is of 120-fold selectivity for LAR versus PTP-1B inhibition. The development of potent enzyme-specific inhibitors is so important that they may serve both as tools to study the role of LAR and as therapeutic agents for treatment of type II diabetes.
Coumarins ; chemical synthesis ; chemistry ; pharmacology ; Enzyme Inhibitors ; chemical synthesis ; chemistry ; pharmacology ; Inhibitory Concentration 50 ; Molecular Structure ; Receptor-Like Protein Tyrosine Phosphatases, Class 2 ; antagonists & inhibitors ; Structure-Activity Relationship

HIV-1 fusion inhibitors are a new class of anti-HIV compounds, which block the entry of HIV into target cells through preventing the fusion between viral and cell plasma membrane and thus interrupt the initial steps of viral replication. T-20 (enfuvirtide), which has been clinically approved as the first fusion inhibitor of HIV-1 by U.S. FDA in 2003, can suppress replication of HIV variants with multi-drug resistance to reverse transcriptase and protease inhibitors. Peptides and small molecules display potent anti-HIV fusion activities by targeting gp41 thus inhibit its fusogenic function. In recent years, with the development of studies on the molecular mechanism of HIV membrane fusion process and the function of gp41, many new fusion inhibitors are found and some have been in advanced clinical trials. This review discusses recent progress in the development of HIV-1 fusion inhibitors targeting the gp41.
Anti-HIV Agents ; chemical synthesis ; chemistry ; pharmacology ; Drug Resistance, Multiple ; HIV Envelope Protein gp41 ; chemical synthesis ; chemistry ; pharmacology ; HIV Fusion Inhibitors ; chemical synthesis ; chemistry ; pharmacology ; HIV Infections ; drug therapy ; HIV-1 ; drug effects ; physiology ; Humans ; Peptide Fragments ; chemical synthesis ; chemistry ; pharmacology ; Peptides ; chemical synthesis ; chemistry ; pharmacology ; Recombinant Fusion Proteins ; chemical synthesis ; chemistry ; pharmacology ; Virus Replication ; drug effects ; alpha 1-Antitrypsin ; chemical synthesis ; chemistry ; pharmacology

Kinases play crucial roles in the life of cell. Their functional abnormity usually leads to many human major diseases including tumors. The prospecting of ATP-competitive small-molecule kinase inhibitors targeting kinases of therapeutic interest has become the focus of researches. Due to the high conservation of the catalytic domain of kinases, the selectivity of kinase inhibitors is poor in general. However, along with the development of structural biology and computer-aided drug design, great progress in the research of selective, ATP-competitive kinase inhibitors has been achieved in recent years. In this account, the review has been made on the development of the design of selective kinase inhibitors.
Adenosine Triphosphate ; chemistry ; Binding, Competitive ; Drug Design ; Molecular Structure ; Protein Binding ; Protein Kinase Inhibitors ; chemical synthesis ; chemistry ; pharmacology

OBJECTIVETo study the roles of protein synthesis inhibitors in long-term potentiation(LTP) and depotentiation(DP) in hippocampal CA1 region of adult rats.

METHODSStandard extracellular recording technique was used to record field EPSP(fEPSP) evoked by Schaffer collateral stimulation from the CA1 subfield of adult rat hippocampal slices. Paired-pulse low-frequency stimulation(PP-LFS) or high-intensity paired-pulse low-frequency stimulation(HI-PP-LFS) was delivered to induce depotentiation 2 h after LTP induction induced by six theta-burst stimulations. Protein synthesis inhibitors were applied before and after LTP induction to study their roles in LTP and DP in hippocampal CA1 region of adult rats.

RESULTSWhen HI-PP-LFS was applied at 2 h after LTP induction, the depotentiation was induced. The mean fEPSP slopes reduced from 346.2%±26.3% to 207.1%±21.6%. This depotentiation was named as partial LTP depotentiation and maintained at least for 30 min. The percentage of depotentiation was 59.81%. Application of protein synthesis inhibitors, anisomycin and cycloheximide prior to tetanus resulted in smaller LTP compared to control group, and almost complete depotentiation was induced by HI-PP-LFS. With application of protein synthesis inhibitors anisomycin and cycloheximide 90 min after LTP induction, HI-PP-LFS still induced partial LTP depotentiation. However, there was no significant difference in the percentage of depotentiation between this group and control group.

CONCLUSIONHI-PP-LFS partially reverses late phase LTP. When protein synthesis inhibitors are applied prior to tetanus, LTP amplitude is markedly reduced, and HI-PP-LFS completely reverses late-phase LTP. Application of protein synthesis inhibitors after LTP induction does not significantly affect either the amplitude or depotentiation of LTP.

Animals ; CA1 Region, Hippocampal ; drug effects ; In Vitro Techniques ; Long-Term Potentiation ; Long-Term Synaptic Depression ; Protein Synthesis Inhibitors ; pharmacology ; Rats

Protein tyrosine phosphatase (PTP) 1B is a potential target for the treatment of diabetes and obesity. Phosphotyrosine (pTyr) is the substrate for PTP1B dephosphorylation. Malonic acid moiety was used herein as a mimic of the phosphate group in pTyr, and novel malonic acid derivatives 1-7 were designed, synthesized and evaluated as PTP1B inhibitors. Results from enzymatic assays indicated that compounds 3 and 4 exhibited potent inhibition against human recombinant PTP1B with IC50 values of 7.66 and 1.88 micromol x L(-1), respectively.
Drug Design ; Enzyme Inhibitors ; chemical synthesis ; chemistry ; pharmacology ; Humans ; Inhibitory Concentration 50 ; Malonates ; chemical synthesis ; chemistry ; pharmacology ; Molecular Structure ; Protein Tyrosine Phosphatase, Non-Receptor Type 1 ; antagonists & inhibitors ; metabolism ; Structure-Activity Relationship

OBJECTIVETo investigate the effect of luteolin on the proliferation and collagen expression of hepatic stellate cells.

METHODSThe effect of luteolin on proliferation and collagen synthesis of hepatic stellate cells isolated from the liver of Wistar rats were determined by (3)H-TdR and (3)H-Pro, and procollagen gene expression was also detected by DIG-labeled gene probe and in situ hybridization.

RESULTSThe proliferation and collagen synthesis were significantly and dose-dependently inhibited by luteolin when the concentrations reached 10 micromol/L and 20 micromol/L respectively (t=2.542, P<0.05; t=3.650, P<0.01). The type I, III procollagen mRNA expression was decreased by 25 micromol/L luteolin, in which the type I procollagen mRNA was reduced with statistical significance (x(2)=6.850, P<0.01).

CONCLUSIONSLuteolin inhibits the proliferation and collagen expression of hepatic stellate cells in vitro. It may have a preventive or therapeutic role in liver fibrosis.

Animals ; Cell Division ; drug effects ; Cells, Cultured ; Collagen ; biosynthesis ; drug effects ; Expectorants ; pharmacology ; Flavonoids ; pharmacology ; Liver ; cytology ; Luteolin ; Protein Synthesis Inhibitors ; pharmacology ; Rats ; Rats, Wistar

Oxidized LDL (OxLDL), a causal factor in atherosclerosis, induces the expression of heat shock proteins (Hsp) in a variety of cells. In this study, we investigated the role of CD36, an OxLDL receptor, and peroxisome proliferator-activated receptor gamma (PPAR gamma) in OxLDL-induced Hsp70 expression. Overexpression of dominant-negative forms of CD36 or knockdown of CD36 by siRNA transfection increased OxLDL-induced Hsp70 protein expression in human monocytic U937 cells, suggesting that CD36 signaling inhibits Hsp70 expression. Similar results were obtained by the inhibition of PPAR gamma activity or knockdown of PPAR gamma expression. In contrast, overexpression of CD36, which is induced by treatment of MCF-7 cells with troglitazone, decreased Hsp70 protein expression induced by OxLDL. Interestingly, activation of PPAR gamma through a synthetic ligand, ciglitazone or troglitazone, decreased the expression levels of Hsp70 protein in OxLDL-treated U937 cells. However, major changes in Hsp70 mRNA levels were not observed. Cycloheximide studies demonstrate that troglitazone attenuates Hsp70 translation but not Hsp70 protein stability. PPAR gamma siRNA transfection reversed the inhibitory effects of troglitazone on Hsp70 translation. These results suggest that CD36 signaling may inhibit stress- induced gene expression by suppressing translation via activation of PPAR gamma in monocytes. These findings reveal a new molecular basis for the anti-inflammatory effects of PPAR gamma.
Antigens, CD36/*physiology ; Cell Line, Tumor ; Chromans/pharmacology ; Cycloheximide/pharmacology ; HSP70 Heat-Shock Proteins/*biosynthesis ; Humans ; Lipoproteins, LDL/pharmacology/*physiology ; Monocytes/drug effects/metabolism ; PPAR gamma/agonists/antagonists & inhibitors/*physiology ; Protein Synthesis Inhibitors/pharmacology ; Signal Transduction ; Thiazolidinediones/pharmacology

Because c-Src and iNOS are key regulatory enzymes in tumorigenesis, a new series of 4-heterocycle amine-3-quinolinecarbonitriles as potent dual inhibitors of both enzymes were designed, synthesized and evaluated as multiple targets agents in cancer therapy. All compounds were evaluated by two related enzyme inhibition assays and an anti-proliferation assay in vitro. The results showed that most compounds inhibited c-Src and iNOS well. The best compound 33 inhibited both enzymes with the IC50 values of 0.0484 micromol x L(-1) and 34.5 micromol x (-1), respectively. Some of the compounds also showed moderate anti-proliferation activities at 10 micromol x L(-1) against colon cancer HT-29 and liver cancer HepG2 cell lines.
Aniline Compounds ; chemical synthesis ; chemistry ; pharmacology ; Antineoplastic Agents ; chemical synthesis ; chemistry ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Drug Delivery Systems ; Drug Design ; Humans ; Nitric Oxide Synthase Type II ; antagonists & inhibitors ; metabolism ; Protein-Tyrosine Kinases ; antagonists & inhibitors ; metabolism ; Quinolines ; chemical synthesis ; chemistry ; pharmacology ; src-Family Kinases

Alzheimer's disease (AD) is a complex neurodegenerative disorder which seriously causes the dementia in elderly people and afflicts millions of people worldwide. Drug discovery for Alzheimer's disease therapy has been a hot research area and a big challenge, in which development of acetylcholinesterase (AChE) inhibitors design was the most active and some AChE inhibitors are commercially available for AD medication already. However, practical using of commercial AChE inhibitors showed their limited usefulness and related adverse effects. Thus, it is extremely urgent to find novel AChE inhibitors with higher potency and less adverse effects. Based on the accurate crystallographic studies about AChE, strategies for multi-binding site AChE inhibitors have been formed, followed by design of the multi-target directed ligands. In this review, the structures and binding modes of commercial AChE inhibitors were briefly discussed, together with the development of AChE inhibitor design for AD therapy: from multi-binding site inhibitors to multi-target directed ligands.
Acetylcholinesterase ; chemistry ; metabolism ; Alzheimer Disease ; drug therapy ; Amyloid Precursor Protein Secretases ; antagonists & inhibitors ; Amyloid beta-Peptides ; metabolism ; Animals ; Aspartic Acid Endopeptidases ; antagonists & inhibitors ; Binding Sites ; Butyrylcholinesterase ; chemistry ; metabolism ; Cholinesterase Inhibitors ; chemical synthesis ; chemistry ; pharmacology ; therapeutic use ; Drug Design ; Humans ; Ligands ; Monoamine Oxidase Inhibitors ; chemical synthesis ; chemistry ; Receptors, N-Methyl-D-Aspartate ; antagonists & inhibitors ; Structure-Activity Relationship

Diabetes mellitus is a common metabolic disease with a high and growing prevalence affecting 4% of the population worldwide, the development of safe and effective therapeutic drug is the major thrust for chemists and pharmacists. To search for active antidiabetic lead compound, we designed and synthesized some novel beta-amino ketone derivatives containing sulfamethoxazole moiety directly through Mannich reaction of sulfamethoxazole, 4-bromoacetophenone and some aromatic aldehydes catalyzed by concentrated hydogen chloride or iodine in the solution of ethanol at 24-40 degrees C with convenient operation, mild reaction condition and satisfactory yield (32%-90%). Their chemical structures were characterized by 1H NMR, 13C NMR, MS and HR-MS. Biological activity tests showed that, in the range of low concentration (5-10 microg x mL(-1)), these title compounds to a certain degree possess protein tyrosine phosphatase 1B (PTP1B) inhibitory activity and a-glucosidase inhibitory activity, moreover, some could activate peroxisome proliferator-activated receptor response element (PPRE) moderately. The PPRE agonist activities of seven compounds are almost 40% of that of Pioglitazone (the positive control), compound 12 shows the strongest activity (66.35%) among them. Thus, it was found that some of 4-(3-(4-bromophenyl)-3-oxo-1-arylpropylamino)-N-(5-methyl-isoxazol-3-yl) benzenesulfonamide containing sulfamethoxazole moiety exhibited antidiabetic activity for the first time.
Glycoside Hydrolase Inhibitors ; Humans ; Hypoglycemic Agents ; chemical synthesis ; chemistry ; pharmacology ; Molecular Structure ; Oxazoles ; chemistry ; Peroxisome Proliferator-Activated Receptors ; agonists ; Protein Tyrosine Phosphatase, Non-Receptor Type 1 ; antagonists & inhibitors ; Response Elements ; Structure-Activity Relationship ; Sulfonamides ; chemistry ; Thiazolidinediones ; pharmacology