Publications by authors named "Eduard Felder"

23 Publications

  • Page 1 of 1

Discovery of Stereospecific PARP-1 Inhibitor Isoindolinone NMS-P515.

ACS Med Chem Lett 2019 Apr 13;10(4):534-538. Epub 2019 Mar 13.

Oncology, Nerviano Medical Sciences S.r.l., Viale Pasteur 10, 20014 Nerviano, Milan, Italy.

Poly(ADP-ribose) polymerase-1 (PARP-1) is an enzyme involved in signaling and repair of DNA single strand breaks. PARP-1 employs NAD to modify substrate proteins via the attachment of poly(ADP-ribose) chains. PARP-1 is a well established target in oncology, as testified by the number of marketed drugs (e.g., Lynparza, Rubraca, Zejula, and Talzenna) used for the treatment of ovarian, breast, and prostate tumors. Efforts in investigating an uncharted region of the previously identified isoindolinone carboxamide series delivered ()- (NMS-P515), a potent inhibitor of PARP-1 both in biochemical (: 0.016 μM) and cellular (IC: 0.027 μM) assays. Cocrystal structure allowed explaining NMS-P515 stereospecific inhibition of the target. After having ruled out potential loss of enantiopurity in vitro and in vivo, NMS-P515 was synthesized in an asymmetric fashion. NMS-P515 ADME profile and its antitumor activity in a mouse xenograft cancer model render the compound eligible for further optimization.
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http://dx.doi.org/10.1021/acsmedchemlett.8b00569DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6466814PMC
April 2019

The target landscape of clinical kinase drugs.

Science 2017 12;358(6367)

Chair of Proteomics and Bioanalytics, Technical University of Munich (TUM), Freising, Germany.

Kinase inhibitors are important cancer therapeutics. Polypharmacology is commonly observed, requiring thorough target deconvolution to understand drug mechanism of action. Using chemical proteomics, we analyzed the target spectrum of 243 clinically evaluated kinase drugs. The data revealed previously unknown targets for established drugs, offered a perspective on the "druggable" kinome, highlighted (non)kinase off-targets, and suggested potential therapeutic applications. Integration of phosphoproteomic data refined drug-affected pathways, identified response markers, and strengthened rationale for combination treatments. We exemplify translational value by discovering SIK2 (salt-inducible kinase 2) inhibitors that modulate cytokine production in primary cells, by identifying drugs against the lung cancer survival marker MELK (maternal embryonic leucine zipper kinase), and by repurposing cabozantinib to treat FLT3-ITD-positive acute myeloid leukemia. This resource, available via the ProteomicsDB database, should facilitate basic, clinical, and drug discovery research and aid clinical decision-making.
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http://dx.doi.org/10.1126/science.aan4368DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6542668PMC
December 2017

Discovery of Entrectinib: A New 3-Aminoindazole As a Potent Anaplastic Lymphoma Kinase (ALK), c-ros Oncogene 1 Kinase (ROS1), and Pan-Tropomyosin Receptor Kinases (Pan-TRKs) inhibitor.

J Med Chem 2016 Apr 30;59(7):3392-408. Epub 2016 Mar 30.

Oncology, Nerviano Medical Sciences Srl , Viale Pasteur 10, 20014 Nerviano, Milan, Italy.

Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase responsible for the development of different tumor types. Despite the remarkable clinical activity of crizotinib (Xalkori), the first ALK inhibitor approved in 2011, the emergence of resistance mutations and of brain metastases frequently causes relapse in patients. Within our ALK drug discovery program, we identified compound 1, a novel 3-aminoindazole active on ALK in biochemical and in cellular assays. Its optimization led to compound 2 (entrectinib), a potent orally available ALK inhibitor active on ALK-dependent cell lines, efficiently penetrant the blood-brain barrier (BBB) in different animal species and highly efficacious in in vivo xenograft models. Moreover, entrectinib resulted to be strictly potent on the closely related tyrosine kinases ROS1 and TRKs recently found constitutively activated in several tumor types. Entrectinib is currently undergoing phase I/II clinical trial for the treatment of patients affected by ALK-, ROS1-, and TRK-positive tumors.
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http://dx.doi.org/10.1021/acs.jmedchem.6b00064DOI Listing
April 2016

Entrectinib, a Pan-TRK, ROS1, and ALK Inhibitor with Activity in Multiple Molecularly Defined Cancer Indications.

Mol Cancer Ther 2016 04 3;15(4):628-39. Epub 2016 Mar 3.

Nerviano Medical Sciences srl, Nerviano, Milan, Italy.

Activated ALK and ROS1 tyrosine kinases, resulting from chromosomal rearrangements, occur in a subset of non-small cell lung cancers (NSCLC) as well as other tumor types and their oncogenic relevance as actionable targets has been demonstrated by the efficacy of selective kinase inhibitors such as crizotinib, ceritinib, and alectinib. More recently, low-frequency rearrangements of TRK kinases have been described in NSCLC, colorectal carcinoma, glioblastoma, and Spitzoid melanoma. Entrectinib, whose discovery and preclinical characterization are reported herein, is a novel, potent inhibitor of ALK, ROS1, and, importantly, of TRK family kinases, which shows promise for therapy of tumors bearing oncogenic forms of these proteins. Proliferation profiling against over 200 human tumor cell lines revealed that entrectinib is exquisitely potent in vitro against lines that are dependent on the drug's pharmacologic targets. Oral administration of entrectinib to tumor-bearing mice induced regression in relevant human xenograft tumors, including the TRKA-dependent colorectal carcinoma KM12, ROS1-driven tumors, and several ALK-dependent models of different tissue origins, including a model of brain-localized lung cancer metastasis. Entrectinib is currently showing great promise in phase I/II clinical trials, including the first documented objective responses to a TRK inhibitor in colorectal carcinoma and in NSCLC. The drug is, thus, potentially suited to the therapy of several molecularly defined cancer settings, especially that of TRK-dependent tumors, for which no approved drugs are currently available. Mol Cancer Ther; 15(4); 628-39. ©2016 AACR.
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http://dx.doi.org/10.1158/1535-7163.MCT-15-0758DOI Listing
April 2016

Discovery of 2-[1-(4,4-Difluorocyclohexyl)piperidin-4-yl]-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carboxamide (NMS-P118): A Potent, Orally Available, and Highly Selective PARP-1 Inhibitor for Cancer Therapy.

J Med Chem 2015 Sep 26;58(17):6875-98. Epub 2015 Aug 26.

Oncology, Nerviano Medical Sciences Srl , Viale Pasteur 10, 20014 Nerviano, Milan, Italy.

The nuclear protein poly(ADP-ribose) polymerase-1 (PARP-1) has a well-established role in the signaling and repair of DNA and is a prominent target in oncology, as testified by the number of candidates in clinical testing that unselectively target both PARP-1 and its closest isoform PARP-2. The goal of our program was to find a PARP-1 selective inhibitor that would potentially mitigate toxicities arising from cross-inhibition of PARP-2. Thus, an HTS campaign on the proprietary Nerviano Medical Sciences (NMS) chemical collection, followed by SAR optimization, allowed us to discover 2-[1-(4,4-difluorocyclohexyl)piperidin-4-yl]-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carboxamide (NMS-P118, 20by). NMS-P118 proved to be a potent, orally available, and highly selective PARP-1 inhibitor endowed with excellent ADME and pharmacokinetic profiles and high efficacy in vivo both as a single agent and in combination with Temozolomide in MDA-MB-436 and Capan-1 xenograft models, respectively. Cocrystal structures of 20by with both PARP-1 and PARP-2 catalytic domain proteins allowed rationalization of the observed selectivity.
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http://dx.doi.org/10.1021/acs.jmedchem.5b00680DOI Listing
September 2015

Novel pyrrole carboxamide inhibitors of JAK2 as potential treatment of myeloproliferative disorders.

Bioorg Med Chem 2015 May 28;23(10):2387-407. Epub 2015 Mar 28.

Nerviano Medical Sciences S.r.l., Oncology, Viale Pasteur 10, 20014 Nerviano (MI), Italy.

Compound 1, a hit from the screening of our chemical collection displaying activity against JAK2, was deconstructed for SAR analysis into three regions, which were explored. A series of compounds was synthesized leading to the identification of the potent and orally bioavailable JAK2 inhibitor 16 (NMS-P830), which showed an encouraging tumour growth inhibition in SET-2 xenograft tumour model, with evidence for JAK2 pathway suppression demonstrated by in vivo pharmacodynamic effects.
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http://dx.doi.org/10.1016/j.bmc.2015.03.059DOI Listing
May 2015

Discovery of 2-(cyclohexylmethylamino)pyrimidines as a new class of reversible valosine containing protein inhibitors.

J Med Chem 2014 Dec 12;57(24):10443-54. Epub 2014 Dec 12.

Oncology, Nerviano Medical Sciences S.r.l. , Viale Pasteur 10, 20014 Nerviano, Milan, Italy.

Valosine-containing protein (VCP), also known as p97 or cdc48 in yeast, is a highly abundant protein belonging to the AAA ATPase family involved in a number of essential cellular functions, including ubiquitin-proteasome mediated protein degradation, Golgi reassembly, transcription activation, and cell cycle control. Altered expression of VCP has been detected in many cancer types sometimes associated with poor prognosis. Furthermore, VCP mutations are causative of some neurodegenerative disorders. In this paper we report the discovery, synthesis, and structure-activity relationships of substituted 2-aminopyrimidines, representing a new class of reversible VCP inhibitors. This class of compounds, identified in a HTS campaign against recombinant VCP, has been progressively expanded and manipulated to increase biochemical potency and gain cellular activity.
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http://dx.doi.org/10.1021/jm501313xDOI Listing
December 2014

Optimization of diarylthiazole B-raf inhibitors: identification of a compound endowed with high oral antitumor activity, mitigated hERG inhibition, and low paradoxical effect.

ChemMedChem 2015 Feb 27;10(2):276-95. Epub 2014 Nov 27.

Nerviano Medical Sciences Srl, Business Unit Oncology, Viale Pasteur 10, 20014 Nerviano (MI) (Italy).

Aberrant activation of the mitogen-activated protein kinase (MAPK)-mediated pathway components, RAF-MEK-ERK, is frequently observed in human cancers and clearly contributes to oncogenesis. As part of a project aimed at finding inhibitors of B-Raf, a key player in the MAPK cascade, we originally identified a thiazole derivative endowed with high potency and selectivity, optimal in vitro ADME properties, and good pharmacokinetic profiles in rodents, but that suffers from elevated hERG inhibitory activity. An optimization program was thus undertaken, focused mainly on the elaboration of the R(1) and R(2) groups of the scaffold. This effort ultimately led to N-(4-{2-(1-cyclopropylpiperidin-4-yl)-4-[3-(2,5-difluorobenzenesulfonylamino)-2-fluorophenyl]thiazol-5-yl}-pyridin-2-yl)acetamide (20), which maintains favorable in vitro and in vivo properties, but lacks hERG liability. Besides exhibiting potent antiproliferative activity against only cell lines bearing B-Raf V600E or V600D mutations, compound 20 also intriguingly shows a weaker "paradoxical" activation of MEK in non-mutant B-Raf cells than other known B-Raf inhibitors. It also demonstrates very good efficacy in vivo against the A375 xenograft melanoma model (tumor volume inhibition >90% at 10 mg kg(-1) ); it is therefore a suitable candidate for preclinical development.
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http://dx.doi.org/10.1002/cmdc.201402424DOI Listing
February 2015

Pyrrole-3-carboxamides as potent and selective JAK2 inhibitors.

Bioorg Med Chem 2014 Sep 21;22(17):4998-5012. Epub 2014 Jun 21.

Nerviano Medical Sciences S.r.l., Oncology, Viale Pasteur 10, 20014 Nerviano (MI), Italy.

We report herein the discovery, structure guided design, synthesis and biological evaluation of a novel class of JAK2 inhibitors. Optimization of the series led to the identification of the potent and orally bioavailable JAK2 inhibitor 28 (NMS-P953). Compound 28 displayed significant tumour growth inhibition in SET-2 xenograft tumour model, with a mechanism of action confirmed in vivo by typical modulation of known biomarkers, and with a favourable pharmacokinetic and safety profile.
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http://dx.doi.org/10.1016/j.bmc.2014.06.025DOI Listing
September 2014

Fragment-based hit discovery and structure-based optimization of aminotriazoloquinazolines as novel Hsp90 inhibitors.

Bioorg Med Chem 2014 Aug 14;22(15):4135-50. Epub 2014 Jun 14.

Oncology, Nerviano Medical Sciences, Viale Pasteur 10, 20014 Nerviano (MI), Italy. Electronic address:

In the last decade the heat shock protein 90 (Hsp90) has emerged as a major therapeutic target and many efforts have been dedicated to the discovery of Hsp90 inhibitors as new potent anticancer agents. Here we report the identification of a novel class of Hsp90 inhibitors by means of a biophysical FAXS-NMR based screening of a library of fragments. The use of X-ray structure information combined with modeling studies enabled the fragment evolution of the initial triazoloquinazoline hit to a class of compounds with nanomolar potency and drug-like properties suited for further lead optimization.
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http://dx.doi.org/10.1016/j.bmc.2014.05.056DOI Listing
August 2014

The TPM3-NTRK1 rearrangement is a recurring event in colorectal carcinoma and is associated with tumor sensitivity to TRKA kinase inhibition.

Mol Oncol 2014 Dec 12;8(8):1495-507. Epub 2014 Jun 12.

Nerviano Medical Sciences S.r.l., Nerviano (Milan), Italy.

The NTRK1 gene encodes Tropomyosin-related kinase A (TRKA), the high-affinity Nerve Growth Factor Receptor. NTRK1 was originally isolated from a colorectal carcinoma (CRC) sample as component of a somatic rearrangement (TPM3-NTRK1) resulting in expression of the oncogenic chimeric protein TPM3-TRKA, but there has been no subsequent report regarding the relevance of this oncogene in CRC. The KM12 human CRC cell line expresses the chimeric TPM3-TRKA protein and is hypersensitive to TRKA kinase inhibition. We report the detailed characterization of the TPM3-NTRK1 genomic rearrangement in KM12 cells and through a cellular screening approach, the identification of NMS-P626, a novel highly potent and selective TRKA inhibitor. NMS-P626 suppressed TPM3-TRKA phosphorylation and downstream signaling in KM12 cells and showed remarkable antitumor activity in mice bearing KM12 tumors. Finally, using quantitative reverse transcriptase PCR and immunohistochemistry (IHC) we identified the TPM3-NTRK1 rearrangement in a CRC clinical sample, therefore suggesting that this chromosomal translocation is indeed a low frequency recurring event in CRC and that such patients might benefit from therapy with TRKA kinase inhibitors.
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http://dx.doi.org/10.1016/j.molonc.2014.06.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5528583PMC
December 2014

Discovery and optimization of pyrrolo[1,2-a]pyrazinones leads to novel and selective inhibitors of PIM kinases.

Bioorg Med Chem 2013 Dec 2;21(23):7364-80. Epub 2013 Oct 2.

Oncology, Nerviano Medical Sciences, viale Pasteur 10, 20014 Nerviano (MI), Italy. Electronic address:

A novel series of PIM inhibitors was derived from a combined effort in natural product-inspired library generation and screening. The novel pyrrolo[1,2-a]pyrazinones initial hits are inhibitors of PIM isoforms with IC50 values in the low micromolar range. The application of a rational optimization strategy, guided by the determination of the crystal structure of the complex in the kinase domain of PIM1 with compound 1, led to the discovery of compound 15a, which is a potent PIM kinases inhibitor exhibiting excellent selectivity against a large panel of kinases, representative of each family. The synthesis, structure-activity relationship studies, and pharmacokinetic data of compounds from this inhibitor class are presented herein. Furthermore, the cellular activities including inhibition of cell growth and modulation of downstream targets are also described.
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http://dx.doi.org/10.1016/j.bmc.2013.09.054DOI Listing
December 2013

Discovery of NMS-E973 as novel, selective and potent inhibitor of heat shock protein 90 (Hsp90).

Bioorg Med Chem 2013 Nov 19;21(22):7047-63. Epub 2013 Sep 19.

Nerviano Medical Sciences S.r.l., Oncology, Viale Pasteur 10, 20014 Nerviano, MI, Italy. Electronic address:

Novel small molecule inhibitors of heat shock protein 90 (Hsp90) were discovered with the help of a fragment based drug discovery approach (FBDD) and subsequent optimization with a combination of structure guided design, parallel synthesis and application of medicinal chemistry principles. These efforts led to the identification of compound 18 (NMS-E973), which displayed significant efficacy in a human ovarian A2780 xenograft tumor model, with a mechanism of action confirmed in vivo by typical modulation of known Hsp90 client proteins, and with a favorable pharmacokinetic and safety profile.
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http://dx.doi.org/10.1016/j.bmc.2013.09.018DOI Listing
November 2013

Structural insight into maternal embryonic leucine zipper kinase (MELK) conformation and inhibition toward structure-based drug design.

Biochemistry 2013 Sep 4;52(37):6380-7. Epub 2013 Sep 4.

Nerviano Medical Sciences , Viale Pasteur 10, 20014 Nerviano, Milan, Italy.

Maternal embryonic leucine zipper kinase (MELK) is upregulated in several types of tumor, including breast, prostate, and brain tumors. Its expression is generally associated with cell survival, cell proliferation, and resistance to apoptosis. Therefore, the potential of MELK inhibitors as therapeutic agents is recently attracting considerable interest. Here we report the first structures of MELK in complex with AMP-PNP and with nanomolar inhibitors. Our studies shed light on the role of the MELK UBA domain, provide a characterization of the kinase active site, and identify key residues for achieving high potency, laying the groundwork for structure-based drug design efforts.
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http://dx.doi.org/10.1021/bi4005864DOI Listing
September 2013

NMS-E973, a novel synthetic inhibitor of Hsp90 with activity against multiple models of drug resistance to targeted agents, including intracranial metastases.

Clin Cancer Res 2013 Jul 14;19(13):3520-32. Epub 2013 May 14.

Department of Biotechnology, Nerviano Medical Sciences Srl, Nerviano (MI), Italy.

Purpose: Recent developments of second generation Hsp90 inhibitors suggested a potential for development of this class of molecules also in tumors that have become resistant to molecular targeted agents. Disease progression is often due to brain metastases, sometimes related to insufficient drug concentrations within the brain. Our objective was to identify and characterize a novel inhibitor of Hsp90 able to cross the blood-brain barrier (BBB).

Experimental Design: Here is described a detailed biochemical and crystallographic characterization of NMS-E973. Mechanism-based anticancer activity was described in cell models, including models of resistance to kinase inhibitors. Pharmacokinetics properties were followed in plasma, tumor, liver, and brain. In vivo activity and pharmacodynamics, as well as the pharmacokinetic/pharmacodynamic relationships, were evaluated in xenografts, including an intracranially implanted melanoma model.

Results: NMS-E973, representative of a novel isoxazole-derived class of Hsp90 inhibitors, binds Hsp90α with subnanomolar affinity and high selectivity towards kinases, as well as other ATPases. It possesses potent antiproliferative activity against tumor cell lines and a favorable pharmacokinetic profile, with selective retention in tumor tissue and ability to cross the BBB. NMS-E973 induces tumor shrinkage in different human tumor xenografts, and is highly active in models of resistance to kinase inhibitors. Moreover, consistent with its brain penetration, NMS-E973 is active also in an intracranially implanted melanoma model.

Conclusions: Overall, the efficacy profile of NMS-E973 suggests a potential for development in different clinical settings, including tumors that have become resistant to molecular targeted agents, particularly in cases of tumors which reside beyond the BBB.
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http://dx.doi.org/10.1158/1078-0432.CCR-12-3512DOI Listing
July 2013

The generation of purinome-targeted libraries as a means to diversify ATP-mimetic chemical classes for lead finding.

Mol Divers 2012 Feb 15;16(1):27-51. Epub 2012 Feb 15.

Oncology Research, Nerviano Medical Sciences, Viale Pasteur 10, 20014, Nerviano, Italy.

The generation of novel chemotypes in support of our oncology research projects expanded in recent years from a canonical design of kinase-targeted compound libraries to a broader interpretation of purinome-targeted libraries (PTL) addressing the specificity of cancer relevant targets such as kinases and ATPases. Successful screening of structurally diverse ATP-binding targets requires compound libraries covering multiple design elements, which may include phosphate surrogate moieties in ATPase inhibitors or far reaching lipophilic residues stabilizing inactive kinase conformations. Here, we exemplify the design and preparation of drug-like combinatorial libraries and report significantly enhanced screening performance on purinomic targets. We compared overall hit rates of PTL with a simultaneously tested unbiased collection of 200,000 compounds and found consistent superiority of the targeted libraries in all cases. We also analyzed the performance of the largest targeted libraries in comparison with each other and often found striking differences in how a specific target responds to various chemotypes and to whole collections.
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http://dx.doi.org/10.1007/s11030-012-9361-6DOI Listing
February 2012

NMS-P937, an orally available, specific small-molecule polo-like kinase 1 inhibitor with antitumor activity in solid and hematologic malignancies.

Mol Cancer Ther 2012 Apr 7;11(4):1006-16. Epub 2012 Feb 7.

Nerviano Medical Sciences Srl, Nerviano, Milan, Italy.

Polo-like kinase 1 (PLK1) is a serine/threonine protein kinase considered to be the master player of cell-cycle regulation during mitosis. It is indeed involved in centrosome maturation, bipolar spindle formation, chromosome separation, and cytokinesis. PLK1 is overexpressed in a variety of human tumors and its overexpression often correlates with poor prognosis. Although five different PLKs are described in humans, depletion or inhibition of kinase activity of PLK1 is sufficient to induce cell-cycle arrest and apoptosis in cancer cell lines and in xenograft tumor models. NMS-P937 is a novel, orally available PLK1-specific inhibitor. The compound shows high potency in proliferation assays having low nanomolar activity on a large number of cell lines, both from solid and hematologic tumors. NMS-P937 potently causes a mitotic cell-cycle arrest followed by apoptosis in cancer cell lines and inhibits xenograft tumor growth with clear PLK1-related mechanism of action at well-tolerated doses in mice after oral administration. In addition, NMS-P937 shows potential for combination in clinical settings with approved cytotoxic drugs, causing tumor regression in HT29 human colon adenocarcinoma xenografts upon combination with irinotecan and prolonged survival of animals in a disseminated model of acute myelogenous leukemia in combination with cytarabine. NMS-P937, with its favorable pharmacologic parameters, good oral bioavailability in rodent and nonrodent species, and proven antitumor activity in different preclinical models using a variety of dosing regimens, potentially provides a high degree of flexibility in dosing schedules and warrants investigation in clinical settings.
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http://dx.doi.org/10.1158/1535-7163.MCT-11-0765DOI Listing
April 2012

Improved synthesis of polyfluorinated L-lysine for 19F NMR-based screening.

Mol Divers 2009 Feb 22;13(1):53-6. Epub 2008 Nov 22.

Department of Chemistry, BU-Oncology, Nerviano Medical Sciences, Viale Pasteur 10, Nerviano, MI, 20014, Italy.

Polyfluorinated N-alpha-Fmoc-is an element of-Boc-L-lysine represents the best-in-class among a set of polyfluorinated amino acids (PFAs) which are useful tools for (19)F NMR-Based Screening. In this communication, optimized reaction conditions that allowed for the multi-gram preparation of this unnatural amino acid are reported.
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http://dx.doi.org/10.1007/s11030-008-9097-5DOI Listing
February 2009

Trifluoroacetic anhydride-mediated solid-phase version of the Robinson-Gabriel synthesis of oxazoles.

J Comb Chem 2005 May-Jun;7(3):463-73

Department of Chemistry, Nerviano Medical Sciences, Viale Pasteur 10, 20014 Nerviano (MI), Italy.

A traceless solid-phase synthesis of oxazoles 4 via Robinson-Gabriel reaction of solid-supported alpha-acylamino ketones 2 has been achieved. The reaction requires that the cyclization precursor be linked to a benzhydrylic-type linker (compounds 2) and that trifluoroacetic anhydride be used as the cyclodehydrating agent. The solvent has a dramatic effect on the latter reaction, which goes to completion and follows a cyclative-type mechanism only when an ethereal solvent is used. Different synthetic routes have been investigated toward assembling compounds 2. The most straightforward one, which we have validated more extensively, comprises the reaction of Merrifield alpha-methoxyphenyl (MAMP) resin with an alpha-amino ketone to form compounds 1, which are, in turn, acylated. Other methodologies and strategies allowing for the synthesis of compounds 1 that have been investigated include direct alkylation of Rink amide resin; reductive amination of the latter with alpha-keto aldehydes; reaction of MAMP resin with alpha-amino alcohols, followed by oxidation; and protection of Rink amide resin with either 2,4-dinitrosulfonyl or allyl group, followed by alkylation and removal of protecting group. In addition, we disclose a novel variant of the Ugi four-component reaction that allows for the preparation of compounds 2 in a single synthetic step.
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http://dx.doi.org/10.1021/cc049831hDOI Listing
July 2005

Derivatization reactions of heterocyclic scaffolds on solid phase: tools for the synthesis of drug-like molecule libraries.

Methods Enzymol 2003 ;369:435-69

Pharmacia Italy S.p.A., Viale Pasteur 10, Nerviano, MI, I-20014, Italy.

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http://dx.doi.org/10.1016/S0076-6879(03)69023-3DOI Listing
February 2004

Key Intermediates in Combinatorial Chemistry: Access to Various Heterocycles from alpha,beta-Unsaturated Ketones on the Solid Phase.

J Org Chem 1998 Feb;63(3):723-727

Novartis Pharma AG, Core Technology Area, Postfach, CH-4002 Basel, Switzerland.

The value of alpha,beta-unsaturated ketones as key intermediates for the combinatorial assembly of four different templates on the solid phase, namely pyrimidines, dihydropyrimidinones, pyridines, and pyrazoles, was explored with individual syntheses of variably substituted model compounds. Starting from aldehydes grafted on polystyrene support, the Wittig and the Claisen-Schmidt reaction conditions were adapted to efficiently prepare alpha,beta-unsaturated ketones on the solid phase. Further derivatization of the alpha,beta-unsaturated ketones to form pyrimidines succeeded with a number of amidines. In a feasibility study, the potential to obtain, in a modular fashion, other small heterocycles from the same intermediates was assessed. In this solid-phase approach alpha,beta-unsaturated carbonyl intermediates can act as a three-carbon component and a primary enamine is utilized to complement the system for pyridine ring formation. Instead, with N-methylurea a dihydropyrimidinone is obtained. As an alternative, substituted hydrazines are incorporated in one orientation, providing pyrazoles with defined regioisomerism. The study indicates that alpha,beta-unsaturated ketones grafted on the solid phase can take a pivotal role as branching points in a number of synthetic diversity schemes and, therefore, represent versatile intermediates for the efficient preparation of combinatorial small molecule libraries.
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http://dx.doi.org/10.1021/jo971620uDOI Listing
February 1998