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Daniela Montesarchio

Publications and source records attributed to Daniela Montesarchio.

11 recordsLinked to original sources
PubMed2007

A new competitive fluorescence assay for the detection of patulin toxin.

Patulin is a toxic secondary metabolite of a number of fungal species belonging to the genera Penicillum and Aspergillus. It has been mainly isolated from apples and apple products contaminated with the common storage-rot fungus of apples, Penicillum expansum, but it has also been extracted from rotten fruits, moldy feeds, and stored cheese. Human exposure to patulin can lead to serious health problems, and according to a long-term investigation in rats, the World Health Organization has set a tolerable weekly intake of 7 ppb body weight. The content of patulin in foods has been restricted to 50 ppb in many countries. Conventional analytical detection methods involve chromatographic analyses, such as HPLC, GC, and, more recently, techniques such as LC/MS and GC/MS. However, extensive protocols of sample cleanup are required prior to the analysis, and to accomplish it, expensive analytical instrumentation is necessary. An immunochemical analytical method, based on highly specific antigen-antibody interactions, would be desirable, offering several advantages compared to conventional techniques, i.e., low cost per sample, high selectivity, high sensitivity, and high throughput. In this paper, the synthesis of two new derivatives of patulin is described, along with their conjugation to the bovine serum albumin for the production of polyclonal antibodies. Finally, a fluorescence competitive immunoassay was developed for the on-line detection of patulin.

Animals↗
PubMed2006

Solid-phase synthesis of cyclic PNA and PNA-DNA chimeras.

[structure: see text] A new and versatile on-line automated solid-phase approach to obtain cyclic PNA (I and III) and cyclic PNA-DNA chimeras (II) in highly pure form has been developed. Starting from a Tentagel matrix functionalized with a 3-chloro-4-hydroxyphenylacetic linker, the synthesis of representative, new cyclic molecules by standard peptide and phosphoramidite-based chemistry has been achieved.

Cyclization↗
PubMed2006

Cyclic phosphate-linked oligosaccharides: synthesis and conformational behavior of novel cyclic oligosaccharide analogues.

CyPLOS (cyclic phosphate-linked oligosaccharides), that is, novel cyclic oligosaccharide surrogates, consisting of two, three, and four phenyl-beta-D-glucopyranoside units, 4,6-linked through stable phosphodiester bonds, were prepared by a straightforward and efficient solid-phase protocol. The assembly of the linear precursors was achieved by standard phosphoramidite chemistry on an automated DNA synthesizer, using a suitably protected 4-phosphoramidite derivative of D-glucose as the building block. For the crucial cyclization step a phosphotriester methodology was exploited, followed by a mild basic treatment releasing the desired cyclic molecules in solution in a highly pure form. The cyclic dimer and trimer were also independently prepared by classical solution synthesis, basically following the same approach. The solution structural preferences of the cyclic dimer and trimer, obtained by detailed NMR analysis, are also reported.

Cytochrome P-450 Enzyme System↗
PubMed2005

An efficient and versatile solid-phase synthesis of 5'- and 3'-conjugated oligonucleotides.

[reaction: see text] An easy and efficient solid-phase strategy to obtain 5'- and 3'-oligonucleotide conjugates in highly pure form has been developed. Ad hoc derivatized solid supports, to which the first nucleoside unit can be attached through a phosphate linkage, have been exploited both in a pre- and post-DNA assembly conjugation approach. A number of 5'- or 3'- oligonucleotide conjugates, incorporating a variety of labels covalently linked through a phosphodiester or a phosphoramidate bond, have been synthesized and characterized.

Molecular Structure↗
PubMed2005

An efficient solid phase synthesis of 5'-phosphodiester and phosphoramidate monoester nucleoside analogues.

An easy and efficient strategy to obtain libraries of 5'-phosphodiester and 5'-phosphoramidate monoester nucleoside analogues in a highly pure form has been developed, starting from a new nucleoside based solid support. The nucleoside scaffold has been anchored through a 5'-phosphodiester linkage to Tentagel HL resin, functionalized with a 3-chloro-4-hydroxyphenylacetic linker. The solid phase synthesis of small libraries of 5'-phosphodiester and 5'-phosphoramidate monoester thymidine analogues is also reported.

Amides↗
PubMed2004

Excess electron transfer in G-quadruplex.

The excess electron transfer in a G-quadruplex is successfully probed by using the reaction of hydrated electrons with quadruplex complex of pentamers and the 8-bromoguanine moieties as the detection system.

DNA↗
PubMed2004

Modulating the activity of oligonucleotides by carbohydrate conjugation: solid phase synthesis of sucrose-oligonucleotide hybrids.

In order to expand the repertoire of available oligosaccharide-oligonucleotide hybrids, the on-line solid phase synthesis of oligonucleotides conjugated at the 3'-and/or 5'-end with a preformed disaccharide unit has been performed. The key compound in the synthetic scheme described here is an appropriate phosphoramidite derivative of fully protected sucrose, used in association with a solid support functionalized with DMT-protected sucrose. The sucrose units at both ends of selected oligonucleotide sequences were shown to increase their chemical and enzymatic stability, while not interfering with duplex formation and with the ability of G-rich sequences to adopt a quadruplex structure.

Chromatography, High Pressure Liquid↗
PubMed2003

Synthesis and preliminary biological evaluation of a new pyridocarbazole derivative covalently linked to a thymidine nucleoside as a potential targeted antitumoral agent. I.

The therapy of human cancer is one of the more pursued goals by medicinal chemistry research. Most of the compounds clinically used as a treatment owe their efficacy to their cytotoxic interaction (direct or indirect) with nuclear DNA. This interaction results in the inhibition of DNA synthesis and the degradation of nucleic strands. Ellipticine is a naturally occurring 6H-pyrido[4,3-b]carbazole alkaloid endowed with antitumor activity, and several ellipticine derivatives have been used in clinical trials. We previously reported some 1,4-dimethyl-9H-carbazole derivatives structurally related to ellipticine. The purpose of our research was to transform the pyridocarbazole in a prodrug so that it would have more penetration in the tumor cells and block their replication. Our prodrug is slowly hydrolyzed in human plasma in the corresponding acid. From these preliminary results, we deduce that our compound can block cellular replication. Our hypothesis is that the antitumoral activity is probably related to the induction of damage to DNA, without cellular lysis in the short term.

Antineoplastic Agents↗
PubMedDate not supplied

Glycomimetics as decorating motifs for oligonucleotides: solid-phase synthesis, stability, and hybridization properties of carbopeptoid-oligonucleotide conjugates.

The online solid-phase synthesis of oligonucleotides conjugated at the 3' end with [1-6]-linked oligosaccharide mimics having the O-glycosidic linkages replaced by amide bonds is here described. The assembly of the carbohydrate domain has been carried out by exploiting classical solid phase peptide synthetic protocols, starting from solid supports functionalized with 1-azido sugars, in association with suitably protected 1-azido uronic acids of glucose and lactose, chosen as model addition monomers. After the insertion of a flexible linker, elongation of the oligodeoxyribonucleotide (ODN) chain was performed by standard automated phosphoramidite protocols. 3'-Glycoconjugated 18-mers exhibited an increased enzymatic stability with respect to the same unmodified ODN sequence. UV thermal denaturation experiments showed that the presence of the oligosaccharide tail at the 3' end of the oligonucleotides did not negatively interfere with their duplex formation abilities.

Base Pairing↗
PubMedDate not supplied

New solid supports linking nucleoside scaffolds.

An easy and efficient strategy to obtain new nucleoside based solid supports in which the nucleoside moieties have been anchored to the solid support through the nucleobase is here proposed. A simple and efficient solid-phase synthesis of 5' and 3'-derivatized uridine analogues has so been developed, following methodologies well established in organic chemistry.

Chemistry, Organic↗