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Detection and removal of bladder cancer lesions at an early stage is crucial for preventing tumor relapse and progression. This study aimed to develop a new technological platform for the visualization of small and flat urothelial lesions of high-grade bladder carcinoma in situ (CIS). We found that the integrin α5β1, overexpressed in bladder cancer cell lines, murine orthotopic bladder cancer and human bladder CIS, can be exploited as a receptor for targeted delivery of GNRs functionalized with the cyclic CphgisoDGRG peptide (

We present a modular system for the quantitative characterization of the piezoelectric coefficient of piezoelectric polymers and soft polymeric nanocomposites in the compression mode. Our approach is based on an apparatus providing spectral information on the electro-mechanical response in aselected range of frequencies of compressive loads (10–1200 Hz), with high sensitivity (down to 0.5 pC/N) and automated data acquisition modalities, enabling repeatability and reproducibility of the electro-mechanical characterization in the low-force regime (0.1 N 1.5 N). The system is modular and can be developed to cover the 2 mHz-1.2 kHz frequency range in charge mode and the 2 μHz-1200 Hz in voltage mode. We calibrated and validated the apparatus functionality using a commercial PVDF piezoelectric polymer. The suitability of the system for the quantitative measurements of the piezoelectricity of soft polymeric nanocomposites was then assessed by performing measurements of a novel piezoelectric nanocomposite material. This consisted of a polydimethylsiloxane (PDMS) matrix with embedded BaTiO3 nanoparticles, engineered with functional surface coatings to favor their homogeneous dispersion into the polymer. The proposed system demonstrated to be an effective solution for the systematic characterization of the electro-mechanical conversion properties of soft piezoelectric materials in view of soft robotics and energy harvesting applications.

Lysolipid-containing thermosensitive liposomes (LTSL) have gained attention for triggered release of chemotherapeutics. Superparamagnetic iron oxide nanoparticles (SPION) offers multimodal imaging and hyperthermia therapy opportunities as a promising theranostic agent. Combining LTSL with SPION may further enhance their performance and functionality of LTSL. However, a major challenge in clinical translation of nanomedicine is the poor scalability and complexity of their preparation process. Exploiting the nature of self-assembly, nanoprecipitation is a simple and scalable technique for preparing liposomes. Herein, we developed a novel SPION-incorporated lysolipid-containing thermosensitive liposome (mLTSL10) formulation using nanoprecipitation. The formulation and processing parameters were carefully designed to ensure high reproducibility and stability of mLTSL10. The effect of solvent, aqueous-to-organic volume ratio, SPION concentration on the mLTSL10 size and dispersity was investigated. mLTSL10 were successfully prepared with a small size (∼100 nm), phase transition temperature at around 42 °C, and high doxorubicin encapsulation efficiency. Indifferent from blank LTSL, we demonstrated that mLTSL10 combining the functionality of both LTSL and SPION can be successfully prepared using a scalable nanoprecipitation approach.

The synthesis of levetiracetam and its enantiomer by deracemization of (±)-2-bromobutyric acid using either ( S )- or ( R )- N -phenylpantolactam as chiral auxiliaries, followed by S N 2 substitution of the bromine atom by a 2-oxopyrrolidin-1-yl group and amidation of the carboxylic acid, is described.

Enantiomerically pure central and planar chiral ferrocenyl cyanohydrins have been used for the synthesis of previously unreported 5-ferrocenyl-oxazolines and a 5-ferrocenyl-thiazoline where the central chirality lies on the carbon bearing the oxygen or the sulfur atom. The epimerization at C 5 of the oxazoline ring has also been investigated.

Enantiopure fluorinated isoxazolidines and amino polyols were obtained from the 1,3-dipolar cycloaddition of allylic fluorides and Z-α-phenyl-N-methylnitrone under environment-friendly conditions.

A synthesis of ferrocenyl-oxazolines is described using an iodide-mediated ring expansion of N-ferrocenoyl-aziridine-2-carboxylic esters. The ring enlargements take place with full stereocontrol, namely net retention of configuration. Modification of the ester function by a Grignard reaction leads to three new types of ferrocenyl-oxazoline carbinol ligands, which were used as chiral ligands in the asymmetric addition of diethylzinc to benzaldehyde (e.e.s ranging from 46 to 62%). The planar chiral ferrocenyl-oxazoline carbinol ligand gave a very good result (e.e. 90%) in the palladium-catalyzed allylic substitution of 1,3-diphenyl prop-2-enylacetate with dimethyl malonate.

Rac-N-substituted pantolactams (5) are readily obtained in medium to good yields by reaction of rac-pantolactone (1) with primary amines under acid catalysis, whether at 250°C in a pressure reactor or under microwave irradiation. It appears that the amine can react with pantolactone at the carbonyl carbon atom to give a hydroxyamide (3) in a reversible way and at the methylene carbon atom to give a γ-amino acid (4). The last one on dehydration would give the corresponding pantolactam (5).

The reactions of thioferrocenoylsilanes with organolithium reagents, dienes and reducing agents which afford α-silyl sulphides, dihydrothiopyranes and α-silyl ferrocenyl thiols, respectively, have been investigated. α-Silyl sulphides were further functionalised through carbodesilylation with aldehydes. We also report the synthesis of a new planar chiral thioferrocenoylsilane that gave good diastereomeric excess in the reaction with t-butyllithium, lithium lutidine and 2,3-dimethylbuta-1,3-diene. The 1,1′-bis-thioferrocenoylsilane, too unstable to be isolated, was trapped in situ with dienes.

Organomanganese halides and organomanganates prepared by transmetalation of organolithium and Grignard reagents add smoothly to the carbonyl moiety of acylsilanes and of substituted aldehydes bearing a chiral center at the a-position affording the desired alcohols in good to excellent yields and with essentially no undesired products from enolization. Comparison of the stereochemical outcome with that observed for other organometallic species, outlines the capability of organomanganese reagents to induce uniformly good diastereoselectivities, in a number of cases significantly higher than reported previously for these reactions. The key role displayed by the R3Si group in promoting high 1,2-asymmetric induction, clearly emerges in the comparison of acylsilane 12 with the corresponding aldehyde 13. The sense of the Cram:anti-Cram selectivity depends upon the nature of the carbonyl reagents engaged in these reactions. © 2001 Elsevier Science B.V. All rights reserved.

Thioacylsilanes containing the ferrocene moiety, easily prepared from the corresponding acylsilanes with Lawesson's reagent at room temperature, can be transformed into vinyl silanes, sulfur heterocycles and sulfines.

The allylation of acylsilanes with tetraallyltin in the presence of catalytic amounts of Sc(OTf) 3 proceeded smoothly to afford the silylated homoallylic alcohols in good yields. Subsequent protiodesilylation gave the formal adducts of the corresponding aldehydes. The homochiral acylsilane 11 gave a reversal of asymmetric induction in the Sc(OTf) 3 catalyzed allylation and in the Sakurai reaction.

Cyclic and open chain α-silyl vinyl sulfides, obtained from thioacylsilanes, react with acid chlorides in the presence of Lewis acid to give thioannulated cyclopentenones and thiofunctionalized enones. The effect of the substituents at silicon on these reactions has been investigated.

ω-Haloacylsilanes 1 were selectively transformed via thioacylsilanes into Z-silyl-enethiols 4 with solid sodium hydrogen carbonate or into 2-silylthiacycloalk-2-enes 5 of common to large ring size with solid sodium hydroxide. Compounds 5 underwent protiodesilylation.

Several new N -Boc-protected α-aminoacylsilanes from l -phenylalanine and l -isoleucine are synthesized via silylcupration of the corresponding imidazolides. The addition reaction of nucleophiles to the carbonyl moiety gives satisfactory yields of highly functionalized β-amino alcohols and statine analogues. The diastereoselectivity ranges from 30 to 98% and depends upon the nature of the C-nucleophile, on the structure of the starting amino acid as well as on the chelating properties of the Lewis acid employed.

The new allylaminosilanes 2a – c , derived from chiral amines, react with benzaldehyde and pivalaldehyde in the presence of SnCl 4 to give homoallylic alcohols 4a – b with enantiomeric excesses of up to 30%.

The results of model investigations concerning 1,4-addition of higher-order cyanocuprate (n-Bu)2Cu(CN)Li2 to 3-alkyl-substituted butenolides are presented.