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Maurizio Taddei

Publications and source records attributed to Maurizio Taddei.

14 recordsLinked to original sources
PubMed2006

Microwaves make hydroformylation a rapid and easy process.

[reaction: see text] Hydroformylation of alkenes can be carried out in a few minutes under microwave activation at a relatively low pressure (40 psi) using commercially available catalysts and ligands. The 80 mL vial of a Discover microwave oven was connected to a cylinder of CO and H2, and after filling the reactor at 40 psi, a mixture of an alkene, the Wilkinson catalyst, and XANTPHOS was submitted to microwave irradiation giving, after 4 min, high conversion into the corresponding aldehyde without formation of the isomerized alkene.

Journal Article↗
PubMed2006

Synthesis of 2-amino-8-oxodecanoic acids (Aodas) present in natural hystone deacetylase inhibitors.

[reaction: see text] Differently substituted 2-amino-8-oxodecanoic acids (Aodas), present in naturally occurring inhibitors of hystone deacetylase (HDAC), have been prepared using a convergent approach. The configuration in position 2 was derived from enantiomerically pure allylglycine or glutamic acid, whereas the stereochemistry of the substituent in position 9 derived from lactic acid or glyceraldehyde derivatives. Starting from allylglycine, (S)-Aodas, protected at the nitrogen as Boc or Fmoc, were obtained in four steps in about 30% overall yield. These products have been used to prepare a simplified analogue of a natural cyclic tetrapeptide HDAC inhibitor by SPPS.

Amination↗
PubMed2006

Chemistry and biology of chromatin remodeling agents: state of art and future perspectives of HDAC inhibitors.

Chromatin remodeling is a fundamental phenomenon in the life of eukaryotic cells, bearing implications to numerous physiological and pathological phenomena. This review outlines the chemistry of natural and synthetic agents endowed with the ability to interfere with such biological function, with a particular emphasis on histone deacetylase (HDAC) inhibitors. Other aspects covered in this article comprise structure activity relationships (SAR) and modes of action at molecular level, including the description of crystal structures of enzyme-inhibitor complexes.

Animals↗
PubMed2004

A new polymer-supported reagent for the synthesis of beta-lactams in solution.

A modified Mukaiyama reagent was prepared on a PS-DVB resin. This reagent was used for the preparation of beta-lactams, using the Staudinger reaction. The products were obtained by generating the ketene from a carboxylic acid under sonication with the resin followed by reaction with the imine. Excess of the imine was removed by reduction followed by acid scavenging.

Indicators and Reagents↗
PubMed2004

Microwave-assisted Paal-Knorr reaction. A rapid approach to substituted pyrroles and furans.

[reaction: see text] An array of tetrasubstituted pyrroles (and trisubstituted furans) was obtained using a simple three-step procedure. Functional homologation of a beta-ketoester with an aldehyde followed by oxidation gave a series of differently substituted 1,4-dicarbonyl compounds that can be rapidly cyclized with the Paal-Knorr procedure carried out under microwave irradiation.

Journal Article↗
PubMed2003

Ionic liquid as a suitable phase for multistep parallel synthesis of an array of isoxazolines.

[reaction: see text]. A parallel array of isoxazoline diamides was prepared using an ionic liquid [bmim][BF4] as the phase where a three-step procedure (Schotten-Baumann, 1,3-dipolar cycloaddition, ester amidation with Me3Al) was carried out. At the end, selective extraction of the final products with diethyl ether allowed simple isolation of the 16 components of the array (Syncore technology).

Journal Article↗
PubMed2003

Solid-phase synthesis of conformationally constrained peptidomimetics based on a 3,6-disubstituted-1,4-diazepan-2,5-dione core.

Starting from a Cl-trytyl linked hydroxylamine, a hydroxamic dipeptide having serine in the second position was prepared by using DMTMM as the coupling agent. Mitsunobu cyclization carried out under microwave heating gave very good yields of a 3,6-disubstituted-perhydro-diazepin-2,5-dione. This heterocycle can be used as a new platform for combinatorial chemistry or as a constraint to rigidify a small peptide.

Azepines↗
PubMed2002

Organometallic chemistry on solid phase. An overview.

Solid-phase organic synthesis (SPOS) is the most important method for the production of combinatorial libraries and with the development of high-throughput screening, libraries are widespread in pharmaceutical and agricultural chemistry. Amongst all the synthetic transformations successfully applied to solid phase, the use of organometallic reagents for the formation of a new carbon-carbon bond has been scarcely pursued. In this overview we collected the most recent examples of the use of organometallic reagents of Li, Mg, Cu, Zn, Si and B for C-C bond formation. The use of organometallic reagents in Pd-catalysed cross-coupling reactions was not reviewed. Highly basic organometallics as organo-lithium and -magnesium reagents have been more largely employed than cuprates and zincates, suggesting that several kinds of resins can withstand relatively strong reaction conditions.

Boranes↗
PubMedDate not supplied

Cellulose beads: a new versatile solid support for microwave- assisted synthesis. Preparation of pyrazole and isoxazole libraries.

The synthesis of libraries of substituted pyrazoles and isoxazoles has been developed via in situ generation of polymer-bound enaminones. The synthetic protocol makes use of commercially available aniline cellulose, a low-cost and versatile biopolymer, under very mild conditions. This new support allowed us to carry out reactions in polar solvents under both conventional heating and MW irradiation without degradation of the polymer. The reaction between cellulose-bound enaminone and hydroxylamine or hydrazines to afford the target heterocycles in high yields directly in solution is the key step. The support can be conveniently recycled.

Cellulose↗
PubMedDate not supplied

Colorimetric tools for solid-phase organic synthesis.

One of the unresolved problems of solid-phase organic synthesis (SPOS) is the availability of general and rapid methods to monitor the transformation of functional groups present in molecules supported on insoluble supports. Color tests, far from providing the ultimate solution, may help in detection (and sometimes in quantification) of different functional groups. In this short review, we have collected most of the methods available and applied in SPOS with an Experimental Section that describes the procedure we have successfully applied to bead analyses in our laboratories.

Journal Article↗
PubMedDate not supplied

Solution phase synthesis of a library of tetrasubstituted pyrrole amides.

An efficient strategy for the solution-phase parallel synthesis of a library of pyrrole-amides is described. Key reactions include functional homologation of beta-ketoesters with a set of aldehydes followed by oxidation to produce a series of differently substituted 1,4-dicarbonyl compounds. Rapid cyclization using a microwave-assisted Paal-Knorr reaction provided a set of 24 pyrrole esters that were further functionalized through a trimethylaluminum-mediated aminolysis to obtain a larger library of 288 diverse pyrrole-3-amides. The tetrasubstitution allows a good exploration of the chemical space around the central pyrrole core. The last step was entirely automated with a Bohdan Myriad personal synthesizer.

Amides↗