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Author Correction: Structure of the PAPP-A BP5 complex reveals mechanism of substrate recognition. Nat Commun 2022; 13:5694. [PMID: 36171222 PMCID: PMC9519949 DOI: 10.1038/s41467-022-33522-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Structure of the PAPP-A BP5 complex reveals mechanism of substrate recognition. Nat Commun 2022; 13:5500. [PMID: 36127359 PMCID: PMC9489782 DOI: 10.1038/s41467-022-33175-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 09/03/2022] [Indexed: 11/09/2022] Open
Abstract
Insulin-like growth factor (IGF) signaling is highly conserved and tightly regulated by proteases including Pregnancy-Associated Plasma Protein A (PAPP-A). PAPP-A and its paralog PAPP-A2 are metalloproteases that mediate IGF bioavailability through cleavage of IGF binding proteins (IGFBPs). Here, we present single-particle cryo-EM structures of the catalytically inactive mutant PAPP-A (E483A) in complex with a peptide from its substrate IGFBP5 (PAPP-ABP5) and also in its substrate-free form, by leveraging the power of AlphaFold to generate a high quality predicted model as a starting template. We show that PAPP-A is a flexible trans-dimer that binds IGFBP5 via a 25-amino acid anchor peptide which extends into the metalloprotease active site. This unique IGFBP5 anchor peptide that mediates the specific PAPP-A-IGFBP5 interaction is not found in other PAPP-A substrates. Additionally, we illustrate the critical role of the PAPP-A central domain as it mediates both IGFBP5 recognition and trans-dimerization. We further demonstrate that PAPP-A trans-dimer formation and distal inter-domain interactions are both required for efficient proteolysis of IGFBP4, but dispensable for IGFBP5 cleavage. Together the structural and biochemical studies reveal the mechanism of PAPP-A substrate binding and selectivity.
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The journey of macromolecular crystallography in pharmaceutical discovery research at Abbvie and BMS. Acta Crystallogr A Found Adv 2021. [DOI: 10.1107/s0108767321099803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Complex of human Melanotransferrin and SC57.32 Fab fragment reveals novel interdomain arrangement with ferric N-lobe and open C-lobe. Sci Rep 2021; 11:566. [PMID: 33436675 PMCID: PMC7804310 DOI: 10.1038/s41598-020-79090-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 12/01/2020] [Indexed: 01/29/2023] Open
Abstract
Melanotransferrin (MTf) is an iron-binding member of the transferrin superfamily that can be membrane-anchored or secreted in serum. On cells, it can mediate transferrin-independent iron uptake and promote proliferation. In serum, it is a transcytotic iron transporter across the blood-brain barrier. MTf has been exploited as a drug delivery carrier to the brain and as an antibody-drug conjugate (ADC) target due to its oncogenic role in melanoma and its elevated expression in triple-negative breast cancer (TNBC). For treatment of TNBC, an MTf-targeting ADC completed a phase I clinical trial (NCT03316794). The structure of its murine, unconjugated Fab fragment (SC57.32) is revealed here in complex with MTf. The MTf N-lobe is in an active and iron-bound, closed conformation while the C-lobe is in an open conformation incompatible with iron binding. This combination of active and inactive domains displays a novel inter-domain arrangement in which the C2 subdomain angles away from the N-lobe. The C2 subdomain also contains the SC57.32 glyco-epitope, which comprises ten protein residues and two N-acetylglucosamines. Our report reveals novel features of MTf and provides a point of reference for MTf-targeting, structure-guided drug design.
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Structure of human DPEP3 in complex with the SC-003 antibody Fab fragment reveals basis for lack of dipeptidase activity. J Struct Biol 2020; 211:107512. [DOI: 10.1016/j.jsb.2020.107512] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 04/10/2020] [Accepted: 04/17/2020] [Indexed: 01/30/2023]
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Identification of Selective Dual ROCK1 and ROCK2 Inhibitors Using Structure-Based Drug Design. J Med Chem 2018; 61:11074-11100. [DOI: 10.1021/acs.jmedchem.8b01098] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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P1808Patients with heart failure with mid-range and reduced left ventricular ejection fraction show similar derangement of cardiac energy and lipid metabolism. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy565.p1808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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P4526Cardiac structure and function do not relate to functional capacity in a Fontan cohort. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx504.p4526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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22244D flow components and kinetic energy: novel imaging biomarkers in heart failure. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx502.2224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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14 Peak turbulent kinetic energy assessed by cardiac magnetic resonance correlates better than aortic valve area with left ventricular parameters in aortic stenosis: Abstract 14 Table 1. BRITISH HEART JOURNAL 2016. [DOI: 10.1136/heartjnl-2016-309668.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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These abstracts have been selected for VIEWING only as ePosters and in print. ePosters will be available on Screen A & B throughout the meeting, Print Posters at the times indicated below. Please refer to the PROGRAM for more details. Eur Heart J Cardiovasc Imaging 2014. [DOI: 10.1093/ehjci/jeu085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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151 MYOCARDIAL PERFUSION, STRAIN AND PRE-CONTRAST T1 VALUES IN MODERATE ASYMPTOMATIC AORTIC STENOSIS. BRITISH HEART JOURNAL 2013. [DOI: 10.1136/heartjnl-2013-304019.151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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13
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Evaluation of immediate dental implant insertion after extraction. Int J Oral Maxillofac Surg 2011. [DOI: 10.1016/j.ijom.2011.07.984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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14
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P1-substituted symmetry-based human immunodeficiency virus protease inhibitors with potent antiviral activity against drug-resistant viruses. J Med Chem 2011; 54:7094-104. [PMID: 21899332 DOI: 10.1021/jm201109t] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Because there is currently no cure for HIV infection, patients must remain on long-term drug therapy, leading to concerns over potential drug side effects and the emergence of drug resistance. For this reason, new and safe antiretroviral agents with improved potency against drug-resistant strains of HIV are needed. A series of HIV protease inhibitors (PIs) with potent activity against both wild-type (WT) virus and drug-resistant strains of HIV was designed and synthesized. The incorporation of substituents with hydrogen bond donor and acceptor groups at the P1 position of our symmetry-based inhibitor series resulted in significant potency improvements against the resistant mutants. By this approach, several compounds, such as 13, 24, and 29, were identified that demonstrated similar or improved potencies compared to 1 against highly mutated strains of HIV derived from patients who previously failed HIV PI therapy. Overall, compound 13 demonstrated the best balance of potency against drug resistant strains of HIV and oral bioavailability in pharmacokinetic studies. X-ray analysis of an HIV PI with an improved resistance profile bound to WT HIV protease is also reported.
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Discovery and characterization of non-ATP site inhibitors of the mitogen activated protein (MAP) kinases. ACS Chem Biol 2011; 6:234-44. [PMID: 21090814 DOI: 10.1021/cb1002619] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Inhibition of protein kinases has validated therapeutic utility for cancer, with at least seven kinase inhibitor drugs on the market. Protein kinase inhibition also has significant potential for a variety of other diseases, including diabetes, pain, cognition, and chronic inflammatory and immunologic diseases. However, as the vast majority of current approaches to kinase inhibition target the highly conserved ATP-binding site, the use of kinase inhibitors in treating nononcology diseases may require great selectivity for the target kinase. As protein kinases are signal transducers that are involved in binding to a variety of other proteins, targeting alternative, less conserved sites on the protein may provide an avenue for greater selectivity. Here we report an affinity-based, high-throughput screening technique that allows nonbiased interrogation of small molecule libraries for binding to all exposed sites on a protein surface. This approach was used to screen both the c-Jun N-terminal protein kinase Jnk-1 (involved in insulin signaling) and p38α (involved in the formation of TNFα and other cytokines). In addition to canonical ATP-site ligands, compounds were identified that bind to novel allosteric sites. The nature, biological relevance, and mode of binding of these ligands were extensively characterized using two-dimensional (1)H/(13)C NMR spectroscopy, protein X-ray crystallography, surface plasmon resonance, and direct enzymatic activity and activation cascade assays. Jnk-1 and p38α both belong to the MAP kinase family, and the allosteric ligands for both targets bind similarly on a ledge of the protein surface exposed by the MAP insertion present in the CMGC family of protein kinases and distant from the active site. Medicinal chemistry studies resulted in an improved Jnk-1 ligand able to increase adiponectin secretion in human adipocytes and increase insulin-induced protein kinase PKB phosphorylation in human hepatocytes, in similar fashion to Jnk-1 siRNA and to rosiglitazone treatment. Together, the data suggest that these new ligand series bind to a novel, allosteric, and physiologically relevant site and therefore represent a unique approach to identify kinase inhibitors.
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2-Pyridyl P1′-Substituted Symmetry-Based Human Immunodeficiency Virus Protease Inhibitors (A-792611 and A-790742) with Potential for Convenient Dosing and Reduced Side Effects. J Med Chem 2009; 52:2571-86. [DOI: 10.1021/jm900044w] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Mutations conferring resistance to a hepatitis C virus (HCV) RNA-dependent RNA polymerase inhibitor alone or in combination with an HCV serine protease inhibitor in vitro. Antimicrob Agents Chemother 2006; 49:4305-14. [PMID: 16189112 PMCID: PMC1251566 DOI: 10.1128/aac.49.10.4305-4314.2005] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Compounds A-782759 (an N-1-aza-4-hydroxyquinolone benzothiadiazine) and BILN-2061 are specific anti-hepatitis C virus (HCV) agents that inhibit the RNA-dependent RNA polymerase and the NS3 serine protease, respectively. Both compounds display potent activity against HCV replicons in tissue culture. In order to characterize the development of resistance to these anti-HCV agents, HCV subgenomic 1b-N replicon cells were cultured with A-782759 alone or in combination with BILN-2061 at concentrations 10 times above their corresponding 50% inhibitory concentrations in the presence of neomycin. Single substitutions in the NS5B polymerase gene (H95Q, N411S, M414L, M414T, or Y448H) resulted in substantial decreases in susceptibility to A-782759. Similarly, replicons containing mutations in the NS5B polymerase gene (M414L or M414T), together with single mutations in the NS3 protease gene (A156V or D168V), conferred high levels of resistance to both A-782759 and BILN-2061. However, the A-782759-resistant mutants remained susceptible to nucleoside and two other classes of nonnucleoside NS5B polymerase inhibitors, as well as interferon. In addition, we found that the frequency of replicons resistant to both compounds was significantly lower than the frequency of resistance to the single compound. Furthermore, the dually resistant mutants displayed significantly reduced replication capacities compared to the wild-type replicon. These findings provide strategic guidance for the future treatment of HCV infection.
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The high tibial osteotomy, open versus closed wedge, a comparison of methods in 108 patients. Arch Orthop Trauma Surg 2005; 125:638-43. [PMID: 16133475 DOI: 10.1007/s00402-005-0004-6] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2004] [Indexed: 01/29/2023]
Abstract
INTRODUCTION One hundred and eight patients with varus gonarthrosis were treated with high tibial osteotomy (HTO) in 2001. Fifty one patients received an open wedge osteotomy by using the 'Puddu' plate and 57 patients received a Coventry-type closing wedge osteotomy. For both groups the follow-up examination period was 22.5 months (253-1009 days). MATERIAL AND METHODS To evaluate the study, radiological and subjective criteria as well as the Lysholm and the Tegner Activity Score were used. Altogether 84 % of the patients were included in the follow-up examination study. RESULTS In both groups a significant improvement of both scores were achieved. Both methods obtained safe and reproducible results for the correction considering the different operation techniques. There were no differences in outcome between the two methods. Satisfactory results were also achieved for early arthrosis of the femoropatellar and the lateral compartment. CONCLUSION Open and closed wedge HTOs obtain significant improvement in patients with medial osteoarthritis of the knee. Using the right technique is very important for good results. For stabilization of the medial ligament we recommend the open wedge osteotomy. The patient should be informed about the routine removal of the metal plate.
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Design, synthesis, and structural analysis of inhibitors of influenza neuraminidase containing a 2,3-disubstituted tetrahydrofuran-5-carboxylic acid core. Bioorg Med Chem Lett 2005; 15:125-8. [PMID: 15582424 DOI: 10.1016/j.bmcl.2004.10.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2004] [Revised: 10/07/2004] [Accepted: 10/07/2004] [Indexed: 11/29/2022]
Abstract
(+/-)-(2R,3R,5R)-[2-(1'-S-acetamido-3'-methyl)butyl-3-methoxycarbonyl]tetrahydrofuran-5-carboxylic acid (9) and (+/-)-(2R,3R,5R)-[2-(1'-S-acetamido-3'-methyl)butyl-3-(4'-imidazolyl)]tetrahydrofuran 5-carboxylic acid (14) were synthesized as inhibitors of influenza neuraminidase (NA). Both compounds 9 and 14 inhibit influenza NA A with an IC(50) of about 0.5 microM and NA B with an IC(50) of 1.0 microM.
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Abstract
BACKGROUND Ras signalling is frequently aberrant in pancreatic cancer so that there is constitutive activation of the phosphatidylinositol 3-kinase (PI3K) and AKT/protein kinase B pathway, as well as the RAF/MEK/ERK pathway. AIMS In the present study we investigated the role of the PI3K/AKT pathway in malignant transformation of pancreatic cancer cells. METHODS A genetic approach was used to interfere with signal transduction in vitro and in vivo. RASN17, a dominant negative mutant of RAS, was applied to inhibit the PI3K/AKT pathway upstream of PI3K. The regulatory p85beta subunit of PI3K and the negative regulator PTEN were utilised to inhibit the pathway at the level of PI3K, and AAA-AKT, a dominant negative mutant of AKT was employed to interfere with PI3K/AKT signalling at the level of AKT. RESULTS Antiproliferative, proapoptotic, and anticancer effects were documented, showing that inhibition of the PI3K pathway in these cell lines suppresses tumour cell growth in vitro and reduces growth in nude mice. CONCLUSIONS The PI3K/AKT pathway represents a potential therapeutic target for pancreatic cancer, and gene therapy may be one approach to produce selective inhibition.
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[Application of the "Taylor Spatial Frame" with unilateral implantation of a medial sledge prosthesis after posttraumatic dislocation of the femur. A complicated progression]. Unfallchirurg 2004; 107:433-6. [PMID: 15060781 DOI: 10.1007/s00113-004-0762-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
For years the Ilizarov fixator has been an established method for the treatment of orthopedic and trauma patients. The Taylor Spatial Frame is a software-navigated hexapod construction on the basis of the Ilizarov fixator. Unicompartmental arthroplasty of the knee is an option especially in medial osteoarthritis. The therapeutic procedure with a complicated development is illustrated by a case report on a patient with post-traumatic deformity of the femur and medial osteoarthritis of the knee.
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MESH Headings
- Arthroplasty, Replacement, Knee/instrumentation
- Arthroplasty, Replacement, Knee/methods
- Combined Modality Therapy
- External Fixators
- Fracture Healing
- Fractures, Closed/complications
- Fractures, Closed/surgery
- Humans
- Knee Dislocation/etiology
- Knee Dislocation/surgery
- Knee Prosthesis
- Male
- Middle Aged
- Osteoarthritis, Knee/complications
- Osteoarthritis, Knee/surgery
- Osteogenesis, Distraction/instrumentation
- Osteogenesis, Distraction/methods
- Treatment Outcome
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Discovery of potent imidazole and cyanophenyl containing farnesyltransferase inhibitors with improved oral bioavailability. Bioorg Med Chem Lett 2003; 13:1571-4. [PMID: 12699757 DOI: 10.1016/s0960-894x(03)00195-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A pyridyl moiety was introduced into a previously developed series of farnesyltransferase inhibitors containing imidazole and cyanophenyl (such as 4), resulting in potent inhibitors with improved pharmacokinetics.
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Corrigendum to ‘Design, Synthesis, and Neuraminidase Inhibitory Activity of GS-4071 Analogues that Utilize a Novel Hydrophobic Paradigm’. Bioorg Med Chem Lett 2003. [DOI: 10.1016/s0960-894x(03)00300-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Aryl tetrahydropyridine inhibitors of farnesyltransferase: bioavailable analogues with improved cellular potency. Bioorg Med Chem Lett 2003; 13:1363-6. [PMID: 12657283 DOI: 10.1016/s0960-894x(03)00094-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Inhibitors of farnesyltransferase are effective against a variety of tumors in mouse models of cancer. Clinical trials to evaluate these agents in humans are ongoing. In our effort to develop new farnesyltransferase inhibitors, we have discovered bioavailable aryl tetrahydropyridines that are potent in cell culture. The design, synthesis, SAR and biological properties of these compounds will be discussed.
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Aryl tetrahydropyridine inhibitors of farnesyltransferase: glycine, phenylalanine and histidine derivatives. Bioorg Med Chem Lett 2003; 13:1359-62. [PMID: 12657282 DOI: 10.1016/s0960-894x(03)00095-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Inhibitors of farnesyltransferase are effective against a variety of tumors in mouse models of cancer. Clinical trials to evaluate these agents in humans are ongoing. In our effort to develop new farnesyltransferase inhibitors, we have discovered a series of aryl tetrahydropyridines that incorporate substituted glycine, phenylalanine and histidine residues. The design, synthesis, SAR and biological properties of these compounds will be discussed.
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Abstract
Combinatorial and structure-based medicinal chemistry strategies were used together to advance a lead compound with an activity of K(i) = 58 microM via a potency enhancement of >70 000-fold to an analogue with an activity of K(i) = 0.8 nM against influenza neuraminidase (A/Tokyo/67). Lead optimization was initiated using molecular modeling and combinatorial chemistry. Protein crystal structures revealed that inconsistent structure-activity relationship (SAR) data resulted from different binding orientations of the inhibitor core five-membered rings from one series to another. Binding modes for a series of compounds showed up to a 180 degrees variation in orientation of the five-membered ring within the active site. Potent analogues were only achieved with chemical series that were observed to bind in the same orientation and yielded consistent SAR. In one series, consistent binding was obtained by an unprecedented occupation of a negatively charged binding pocket by a neutral methyl ester unit. The structural rationale for this novel SAR variation, based on protein crystallographic data, is given.
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Design, synthesis, and neuraminidase inhibitory activity of GS-4071 analogues that utilize a novel hydrophobic paradigm. Bioorg Med Chem Lett 2002; 12:3425-9. [PMID: 12419376 DOI: 10.1016/s0960-894x(02)00732-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Structure-based design has led to the synthesis of a novel analogue of GS-4071, an influenza neuraminidase inhibitor, in which the basic amino group has been replaced by a hydrophobic vinyl group. An X-ray co-crystal structure of the new inhibitor (K(i)=45 nM) bound to the active site shows that the vinyl group occupies the same subsite as the amino group in GS-4071.
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Abstract
The crystal structure of ABT-378 (lopinavir), bound to the active site of HIV-1 protease is described. A comparison with crystal structures of ritonavir, A-78791, and BILA-2450 shows some analogous features with previous reported compounds. A cyclic urea unit in the P(2) position of ABT-378 is novel and makes two bidentate hydrogen bonds with Asp 29 of HIV-1 protease. In addition, a previously unreported shift in the Gly 48 carbonyl position is observed. A discussion of the structural features responsible for its high potency against wild-type HIV protease is given along with an analysis of the effect of active site mutations on potency in in vitro assays.
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30
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58 Design, synthesis and activity of substituted pyrrolidine influenza neuraminidase inhibitors. Antiviral Res 2000. [DOI: 10.1016/s0166-3542(00)90389-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
The effect of a transitory increase in plasma FSH and LH levels during the prepubertal period on puberty has been investigated. Twenty-day-old rats had been bilaterally ovariectomized and 24 hr later they received two ovaries of infantile rats beneath the kidney capsule. These rats exhibited precocious puberty. Animals into which two additional ovaries had been transplanted first and the next day their own ovaries removed showed puberty at the same time as controls. Additional investigations provided evidence that the ovariectomized and ovary implanted rats plasma FSH and LH levels were in the control range four days after implantation. The findings support the assumption that the hypothalamic lesion-induced precocious puberty is due rather to a transitory enhanced release of gonadotropin releasing hormone by the lesion than to the destruction of sex-steroid sensitive structures inhibiting the release of gonadotropic hormones in prepubertal rats.
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[Transthoracic and transesophageal 2-D echocardiography in the diagnosis of peri- and paracardiac tumors]. Dtsch Med Wochenschr 1987; 112:49-52. [PMID: 3803215 DOI: 10.1055/s-2008-1068002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Twelve consecutive patients (five males and seven females, aged 24-61 years) with peri- or paracardial space-occupying lesions were studied by transthoracic and transesophageal 2-D echocardiography (2-DE). The tumor was localized by transthoracic 2-DE in six patients. In four patients the lesion was suspected after transthoracic 2-DE, but only transesophageal 2-DE defined the tumor and separated it from surrounding tissues. In two cases of pericardial tumor transthoracic 2-DE at first misdiagnosed it as pericarditis with pericardial effusion. In eight patients transthoracic and in four transesophageal 2-DE made it possible to assess cardiac function. The findings demonstrate that transthoracic 2-DE may not demonstrate peri- or paracardial tumors; transesophageal 2-DE adds an at times decisive additional diagnostic method.
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