Luca Gentilucci | Università di Bologna (original) (raw)

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Papers by Luca Gentilucci

Research paper thumbnail of Asymmetrische Synthese von Alkylaziridin-2-carbonsäureestern aus chiralen 3′-Benzyloxyaminoimiden

Research paper thumbnail of Microwave-assisted ring expansion of N-acetyl 3′-unsubstituted aziridine in the presence of Lewis acids

Tetrahedron, 2001

The microwave-assisted ring expansion of N-acetyl 3′-unsubstituted aziridine-2-imides and N-acety... more The microwave-assisted ring expansion of N-acetyl 3′-unsubstituted aziridine-2-imides and N-acetyl 3′-unsubstituted aziridine-2-esters to oxazolines is reported. The regioselectivities of the rearrangements depend upon the reaction conditions, such as the Lewis acid selected and the solvent.

Research paper thumbnail of Asymmetric 1,4 addition of Grignard reagents to chiral α,β-unsaturated esters in the presence of Lewis acids

Tetrahedron, 1999

The synthesis of enantiomerically enriched α-amino acids is described, by means of the diastereos... more The synthesis of enantiomerically enriched α-amino acids is described, by means of the diastereoselective conjugate addition of Grignard reagent to (S)-2-acetamidoacrylic ethoxycarbonyl-phenyl-methyl ester 1 and its N-Boc derivative 5 in the presence of Lewis acids. The addition of magnesium organocuprates has also been analysed. The reaction proceeds with good yields and variable diastereoselectivities, depending on the organometallic reagent and on

Research paper thumbnail of A Practical Method for the Synthesis of β-Amino α-Hydroxy Acids. Synthesis of Enantiomerically Pure Hydroxyaspartic Acid and Isoserine

Research paper thumbnail of A New Selective Synthesis of the Ile- a llo -Thr-Gly Tripeptide Fragment of Lysobactin

Organic Letters, 2000

A New Selective Synthesis of the Ile-allo-Thr-Gly Tripeptide Fragment of Lysobactin.

Research paper thumbnail of A Stereoselective Synthesis of (2 R ,3 S )- N -Benzoylphenylisoserine Methyl Ester

Journal of Organic Chemistry, 1998

... Giuliana Cardillo,* Luca Gentilucci, Alessandra Tolomelli, and Claudia Tomasini*. ... Cesare ... more ... Giuliana Cardillo,* Luca Gentilucci, Alessandra Tolomelli, and Claudia Tomasini*. ... Cesare Gennari, Michela Carcano, Monica Donghi, Nicola Mongelli, Ermes Vanotti, and Anna Vulpetti. The Journal of Organic Chemistry 1997 62 (14), pp 4746–4755. ...

Research paper thumbnail of Conjugate addition of hydroxylamino derivatives to alkylidene malonates in the presence of chiral Lewis acids

Tetrahedron-asymmetry, 2001

The conjugate addition of O-benzylhydroxylamine and N,O-bis(trimethylsilyl)hydroxylamine to alkyl... more The conjugate addition of O-benzylhydroxylamine and N,O-bis(trimethylsilyl)hydroxylamine to alkylidene and arylidene malonates in the presence of Lewis acids affords the corresponding β-hydroxylamino derivatives in good yields. The use of Cu(OTf)2 in the presence of chiral bisoxazoline ligands opens the possibility of performing this reaction in a catalytic and enantioselective way.

Research paper thumbnail of One-Pot Synthesis of Poly-Substituted Tetramic Acids for the Preparation of Putative Turn Mimics

Tetrahedron

A one-pot synthesis of poly-substituted tetramic acids and of their six-membered ring analogs hav... more A one-pot synthesis of poly-substituted tetramic acids and of their six-membered ring analogs have been obtained in one step by reaction of N-Boc dipeptides, activated as their O-succinimidyl esters (Boc-AA-AA-OSu), with the sodium anion of dibenzyl malonate. The adducts spontaneously cyclize to form five or six-member rings. To check whether this class of compounds may be used to promote reverse-turn conformations, one adduct was further derivatized. The formation of an hydrogen bond between the NH-Boc and the carbonyl at C2 of the heterocycle is highlighted, upon analysis of the product by IR, 1H NMR and MD techniques, thus suggesting that these compounds are good candidates to promote reverse-turn conformations or other secondary structures and may be used for the formation of new foldamers.

Research paper thumbnail of Dehydro-β-proline Containing α 4 β 1 Integrin Antagonists: Stereochemical Recognition in Ligand–Receptor Interplay

ACS Medicinal Chemistry Letters, 2015

A novel class of dehydro-β-proline-containing peptidomimetics, designed to be effective as α 4 β ... more A novel class of dehydro-β-proline-containing peptidomimetics, designed to be effective as α 4 β 1 integrin ligands, has been developed on the basis of the fundamental requirements for the interactions of these transmembrane receptors with bioactive ligands. Dehydro-β-proline ring has been synthesized through an original pathway, involving ring closing metathesis of a diallylamino derivative. The synthesized products showed to be effective and selective as α 4 β 1 integrin antagonists and displayed IC 50 values in the nanomolar range in cell adhesion inhibition assays and in VCAM-1-induced phosphorylation of extracellular-signal-regulated kinases. Significant activity was observed also toward the homologous integrin α 4 β 7 , while they did not display any activity toward selected members of β 1 , β 2 , and β 3 families. A strong dependence on the stereochemistry of the heterocyclic central core could be observed. The great importance of α 4 β 1 integrin in chronic inflammatory and autoimmune diseases suggests a possible exploitation of these ligands as lead compounds for therapeutic tools development.

Research paper thumbnail of Enantioselective synthesis of aziridine 2,2-dicarboxylates. Part I: Copper(II)-bisoxazoline complex-catalysed Michael reaction on alkylidene malonates

Tetrahedron: Asymmetry, 2002

The preparation of aziridine-2,2-dicarboxylates via 1,4-addition of N, O-bis(trimethylsilyl)hydro... more The preparation of aziridine-2,2-dicarboxylates via 1,4-addition of N, O-bis(trimethylsilyl)hydroxylamine to a,b-unsaturated malonates in the presence of chiral Lewis acids is reported. Good enantioselectivity was observed for conjugate addition catalysed by [Cu(S,S)-Bn-(box)](OTf) 2 on isobutylidene and 3-methylbutylidene malonate.

Research paper thumbnail of ChemInform Abstract: A New Selective Synthesis of the Ile-allo-Thr-Gly Tripeptide Fragment of Lysobactin

ChemInform, 2000

A New Selective Synthesis of the Ile-allo-Thr-Gly Tripeptide Fragment of Lysobactin.

Research paper thumbnail of ChemInform Abstract: Microwave-Assisted Ring Expansion of N-Acetyl 3′-Unsubstituted Aziridine in the Presence of Lewis Acids

Research paper thumbnail of ChemInform Abstract: Conjugate Addition of Hydroxylamino Derivatives to Alkylidene Malonates in the Presence of Chiral Lewis Acids

Research paper thumbnail of Cyclic endomorphin analogs in targeting opioid receptors to achieve pain relief

Future medicinal chemistry, 2014

Endomorphins, the endogenous ligands of the µ-opioid receptor, are attractive candidates for opio... more Endomorphins, the endogenous ligands of the µ-opioid receptor, are attractive candidates for opioid-based pain-relieving agents. These tetrapeptides, with their remarkable affinity for the µ-opioid receptor, display favorable antinociceptive activity when injected directly into the brain of experimental animals. However, the application of endomorphins as clinical analgesics has been impeded by their instability in body fluids and inability to reach the brain after systemic administration. Among numerous modifications of the endomorphin structure aimed at improving their pharmacological properties, cyclization can be viewed as an interesting option. Here, we have summarized recent advances in obtaining endomorphin-based cyclic peptide analogs.

Research paper thumbnail of Ring expansion of N-acyl aziridine-2-imides to oxazoline-4-imides, useful precursors of pure β-Hydroxy α-aminoacids

Tetrahedron Letters, 1997

Optically active N-acyl aziridin¢ 2-imides or 2-carboxylates rearrange to oxazoline-4-imides or 4... more Optically active N-acyl aziridin¢ 2-imides or 2-carboxylates rearrange to oxazoline-4-imides or 4-carboxylates with high regio and stereo control. This ring expansion followed by mild hydrolisis allows the synthesis of enantiomerically pure I~-hydroxy o~-aminoacid pt~ursors.

Research paper thumbnail of Dipeptides containing D-serine or D-isoserine from the same (R)-aziridine-2-imide by a simple reversal of the synthetic procedure

The ring expansion of 3-nnsnbstitnted (R)-aziridine-2-imid~n~~ng dipeptide under acidic condition... more The ring expansion of 3-nnsnbstitnted (R)-aziridine-2-imid~n~~ng dipeptide under acidic conditions gives rise to oxazoline-5-imide regio and stereoselectively, which can be hydrolysed to the dipeptide containing D isoserine. On the other hand the ring opening of 3-nnsnbstituted (R)-aziridine-2-ester dipeptide, easily okined from the same (R)-aziridine, gives the regioisomeric dipqtide containing D-serine. 0 1999 Elsevier Science Ltd. All rights reserved.

Research paper thumbnail of Lewis Acid Promoted Synthesis and Reactivity of β-O-Benzylhydroxylamino Imides Derived from D-Glyceraldehyde

Research paper thumbnail of ChemInform Abstract: Diastereoselective Synthesis of 3′-Unsubstituted N-Boc-Aziridine from a Readily Available Chiral α,β-Unsaturated Imide

ChemInform

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Research paper thumbnail of ChemInform Abstract: Conjugate Addition of Chloride to α,β-Unsaturated Chiral Imides Promoted by BCl3 Derivatives. Part 2

Research paper thumbnail of ChemInform Abstract: Synthesis of New Chiral Auxiliaries Derived from (S)-Tryptophan

Research paper thumbnail of Asymmetrische Synthese von Alkylaziridin-2-carbonsäureestern aus chiralen 3′-Benzyloxyaminoimiden

Research paper thumbnail of Microwave-assisted ring expansion of N-acetyl 3′-unsubstituted aziridine in the presence of Lewis acids

Tetrahedron, 2001

The microwave-assisted ring expansion of N-acetyl 3′-unsubstituted aziridine-2-imides and N-acety... more The microwave-assisted ring expansion of N-acetyl 3′-unsubstituted aziridine-2-imides and N-acetyl 3′-unsubstituted aziridine-2-esters to oxazolines is reported. The regioselectivities of the rearrangements depend upon the reaction conditions, such as the Lewis acid selected and the solvent.

Research paper thumbnail of Asymmetric 1,4 addition of Grignard reagents to chiral α,β-unsaturated esters in the presence of Lewis acids

Tetrahedron, 1999

The synthesis of enantiomerically enriched α-amino acids is described, by means of the diastereos... more The synthesis of enantiomerically enriched α-amino acids is described, by means of the diastereoselective conjugate addition of Grignard reagent to (S)-2-acetamidoacrylic ethoxycarbonyl-phenyl-methyl ester 1 and its N-Boc derivative 5 in the presence of Lewis acids. The addition of magnesium organocuprates has also been analysed. The reaction proceeds with good yields and variable diastereoselectivities, depending on the organometallic reagent and on

Research paper thumbnail of A Practical Method for the Synthesis of β-Amino α-Hydroxy Acids. Synthesis of Enantiomerically Pure Hydroxyaspartic Acid and Isoserine

Research paper thumbnail of A New Selective Synthesis of the Ile- a llo -Thr-Gly Tripeptide Fragment of Lysobactin

Organic Letters, 2000

A New Selective Synthesis of the Ile-allo-Thr-Gly Tripeptide Fragment of Lysobactin.

Research paper thumbnail of A Stereoselective Synthesis of (2 R ,3 S )- N -Benzoylphenylisoserine Methyl Ester

Journal of Organic Chemistry, 1998

... Giuliana Cardillo,* Luca Gentilucci, Alessandra Tolomelli, and Claudia Tomasini*. ... Cesare ... more ... Giuliana Cardillo,* Luca Gentilucci, Alessandra Tolomelli, and Claudia Tomasini*. ... Cesare Gennari, Michela Carcano, Monica Donghi, Nicola Mongelli, Ermes Vanotti, and Anna Vulpetti. The Journal of Organic Chemistry 1997 62 (14), pp 4746–4755. ...

Research paper thumbnail of Conjugate addition of hydroxylamino derivatives to alkylidene malonates in the presence of chiral Lewis acids

Tetrahedron-asymmetry, 2001

The conjugate addition of O-benzylhydroxylamine and N,O-bis(trimethylsilyl)hydroxylamine to alkyl... more The conjugate addition of O-benzylhydroxylamine and N,O-bis(trimethylsilyl)hydroxylamine to alkylidene and arylidene malonates in the presence of Lewis acids affords the corresponding β-hydroxylamino derivatives in good yields. The use of Cu(OTf)2 in the presence of chiral bisoxazoline ligands opens the possibility of performing this reaction in a catalytic and enantioselective way.

Research paper thumbnail of One-Pot Synthesis of Poly-Substituted Tetramic Acids for the Preparation of Putative Turn Mimics

Tetrahedron

A one-pot synthesis of poly-substituted tetramic acids and of their six-membered ring analogs hav... more A one-pot synthesis of poly-substituted tetramic acids and of their six-membered ring analogs have been obtained in one step by reaction of N-Boc dipeptides, activated as their O-succinimidyl esters (Boc-AA-AA-OSu), with the sodium anion of dibenzyl malonate. The adducts spontaneously cyclize to form five or six-member rings. To check whether this class of compounds may be used to promote reverse-turn conformations, one adduct was further derivatized. The formation of an hydrogen bond between the NH-Boc and the carbonyl at C2 of the heterocycle is highlighted, upon analysis of the product by IR, 1H NMR and MD techniques, thus suggesting that these compounds are good candidates to promote reverse-turn conformations or other secondary structures and may be used for the formation of new foldamers.

Research paper thumbnail of Dehydro-β-proline Containing α 4 β 1 Integrin Antagonists: Stereochemical Recognition in Ligand–Receptor Interplay

ACS Medicinal Chemistry Letters, 2015

A novel class of dehydro-β-proline-containing peptidomimetics, designed to be effective as α 4 β ... more A novel class of dehydro-β-proline-containing peptidomimetics, designed to be effective as α 4 β 1 integrin ligands, has been developed on the basis of the fundamental requirements for the interactions of these transmembrane receptors with bioactive ligands. Dehydro-β-proline ring has been synthesized through an original pathway, involving ring closing metathesis of a diallylamino derivative. The synthesized products showed to be effective and selective as α 4 β 1 integrin antagonists and displayed IC 50 values in the nanomolar range in cell adhesion inhibition assays and in VCAM-1-induced phosphorylation of extracellular-signal-regulated kinases. Significant activity was observed also toward the homologous integrin α 4 β 7 , while they did not display any activity toward selected members of β 1 , β 2 , and β 3 families. A strong dependence on the stereochemistry of the heterocyclic central core could be observed. The great importance of α 4 β 1 integrin in chronic inflammatory and autoimmune diseases suggests a possible exploitation of these ligands as lead compounds for therapeutic tools development.

Research paper thumbnail of Enantioselective synthesis of aziridine 2,2-dicarboxylates. Part I: Copper(II)-bisoxazoline complex-catalysed Michael reaction on alkylidene malonates

Tetrahedron: Asymmetry, 2002

The preparation of aziridine-2,2-dicarboxylates via 1,4-addition of N, O-bis(trimethylsilyl)hydro... more The preparation of aziridine-2,2-dicarboxylates via 1,4-addition of N, O-bis(trimethylsilyl)hydroxylamine to a,b-unsaturated malonates in the presence of chiral Lewis acids is reported. Good enantioselectivity was observed for conjugate addition catalysed by [Cu(S,S)-Bn-(box)](OTf) 2 on isobutylidene and 3-methylbutylidene malonate.

Research paper thumbnail of ChemInform Abstract: A New Selective Synthesis of the Ile-allo-Thr-Gly Tripeptide Fragment of Lysobactin

ChemInform, 2000

A New Selective Synthesis of the Ile-allo-Thr-Gly Tripeptide Fragment of Lysobactin.

Research paper thumbnail of ChemInform Abstract: Microwave-Assisted Ring Expansion of N-Acetyl 3′-Unsubstituted Aziridine in the Presence of Lewis Acids

Research paper thumbnail of ChemInform Abstract: Conjugate Addition of Hydroxylamino Derivatives to Alkylidene Malonates in the Presence of Chiral Lewis Acids

Research paper thumbnail of Cyclic endomorphin analogs in targeting opioid receptors to achieve pain relief

Future medicinal chemistry, 2014

Endomorphins, the endogenous ligands of the µ-opioid receptor, are attractive candidates for opio... more Endomorphins, the endogenous ligands of the µ-opioid receptor, are attractive candidates for opioid-based pain-relieving agents. These tetrapeptides, with their remarkable affinity for the µ-opioid receptor, display favorable antinociceptive activity when injected directly into the brain of experimental animals. However, the application of endomorphins as clinical analgesics has been impeded by their instability in body fluids and inability to reach the brain after systemic administration. Among numerous modifications of the endomorphin structure aimed at improving their pharmacological properties, cyclization can be viewed as an interesting option. Here, we have summarized recent advances in obtaining endomorphin-based cyclic peptide analogs.

Research paper thumbnail of Ring expansion of N-acyl aziridine-2-imides to oxazoline-4-imides, useful precursors of pure β-Hydroxy α-aminoacids

Tetrahedron Letters, 1997

Optically active N-acyl aziridin¢ 2-imides or 2-carboxylates rearrange to oxazoline-4-imides or 4... more Optically active N-acyl aziridin¢ 2-imides or 2-carboxylates rearrange to oxazoline-4-imides or 4-carboxylates with high regio and stereo control. This ring expansion followed by mild hydrolisis allows the synthesis of enantiomerically pure I~-hydroxy o~-aminoacid pt~ursors.

Research paper thumbnail of Dipeptides containing D-serine or D-isoserine from the same (R)-aziridine-2-imide by a simple reversal of the synthetic procedure

The ring expansion of 3-nnsnbstitnted (R)-aziridine-2-imid~n~~ng dipeptide under acidic condition... more The ring expansion of 3-nnsnbstitnted (R)-aziridine-2-imid~n~~ng dipeptide under acidic conditions gives rise to oxazoline-5-imide regio and stereoselectively, which can be hydrolysed to the dipeptide containing D isoserine. On the other hand the ring opening of 3-nnsnbstituted (R)-aziridine-2-ester dipeptide, easily okined from the same (R)-aziridine, gives the regioisomeric dipqtide containing D-serine. 0 1999 Elsevier Science Ltd. All rights reserved.

Research paper thumbnail of Lewis Acid Promoted Synthesis and Reactivity of β-O-Benzylhydroxylamino Imides Derived from D-Glyceraldehyde

Research paper thumbnail of ChemInform Abstract: Diastereoselective Synthesis of 3′-Unsubstituted N-Boc-Aziridine from a Readily Available Chiral α,β-Unsaturated Imide

ChemInform

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Research paper thumbnail of ChemInform Abstract: Conjugate Addition of Chloride to α,β-Unsaturated Chiral Imides Promoted by BCl3 Derivatives. Part 2

Research paper thumbnail of ChemInform Abstract: Synthesis of New Chiral Auxiliaries Derived from (S)-Tryptophan