Quantum sensors for dynamical tracking of chemical processes

Quantum photonics has demonstrated its potential for enhanced sensing. Current sources of quantum light states tailored to measuring, allow to monitor phenomena evolving on time scales of the order of the second. These are characteristic of product accumulation in chemical reactions of technologically interest, in particular those involving chiral compounds. Here we adopt a quantum multiparameter approach to investigate the dynamic process of sucrose acid hydrolysis as a test bed for such applications. The estimation is made robust by monitoring different parameters at once

Asymmetric Synthesis of Spirooxindoles via Nucleophilic Epoxidation Promoted by Bifunctional Organocatalysts

Taking into account the postulated reaction mechanism for the organocatalytic epoxidation of electron-poor olefins developed by our laboratory, we have investigated the key factors able to positively influence the H-bond network installed inside the substrate/catalyst/oxidizing agent. With this aim, we have: (i) tested a few catalysts displaying various effects that noticeably differ in terms of steric hindrance and electron demand; (ii) employed α-alkylidene oxindoles decorated with different substituents on the aromatic ring (11a-g), the exocylic double bond (11h-l), and the amide moiety (11m-v). The observed results suggest that the modification of the electron-withdrawing group (EWG) weakly conditions the overall outcomes, and conversely a strong influence is unambiguously ascribable to either theN-protected orN-unprotected lactam framework. Specifically, when the NH free substrates (11m-u) are employed, an inversion of the stereochemical control is observed, while the introduction of a Boc protecting group affords the desired product12vin excellent enantioselectivity (97:3er)

Spermine oxidase induces DNA damage and sensitizes fusion negative rhabdomyosarcoma cells to irradiation

Rhabdomyosarcoma (RMS) is a pediatric myogenic soft tissue sarcoma that includes fusion-positive (FP) and fusion-negative (FN) molecular subtypes. FP-RMS expresses PAX3-FOXO1 fusion protein and often shows dismal prognosis. FN-RMS shows cytogenetic abnormalities and frequently harbors RAS pathway mutations. Despite the multimodal heavy chemo and radiation therapeutic regimens, high risk metastatic/recurrent FN-RMS shows a 5-year survival less than 30% due to poor sensitivity to chemo-radiotherapy. Therefore, the identification of novel targets is needed. Polyamines (PAs) such as putrescine (PUT), spermidine (SPD) and spermine (SPM) are low-molecular-mass highly charged molecules whose intracellular levels are strictly modulated by specific enzymes. Among the latter, spermine oxidase (SMOX) regulates polyamine catabolism oxidizing SPM to SPD, which impacts cellular processes such as apoptosis and DNA damage response. Here we report that low SMOX levels are associated with a worse outcome in FN-RMS, but not in FP-RMS, patients. Consistently, SMOX expression is downregulated in FN-RMS cell lines as compared to normal myoblasts. Moreover, SMOX transcript levels are reduced FN-RMS cells differentiation, being indirectly downregulated by the muscle transcription factor MYOD. Noteworthy, forced expression of SMOX in two cell lines derived from high-risk FN-RMS: 1) reduces SPM and upregulates SPD levels; 2) induces G0/G1 cell cycle arrest followed by apoptosis; 3) impairs anchorage-independent and tumor spheroids growth; 4) inhibits cell migration; 5) increases γH2AX levels and foci formation indicative of DNA damage. In addition, forced expression of SMOX and irradiation synergize at activating ATM and DNA-PKCs, and at inducing γH2AX expression and foci formation, which suggests an enhancement in DNA damage response. Irradiated SMOX-overexpressing FN-RMS cells also show significant decrease in both colony formation capacity and spheroids growth with respect to single approaches. Thus, our results unveil a role for SMOX as inhibitor of tumorigenicity of FN-RMS cells in vitro. In conclusion, our in vitro results suggest that SMOX induction could be a potential combinatorial approach to sensitize FN-RMS to ionizing radiation and deserve further in-depth studies

SYNTHESIS AND AMINATION OF ALLYLSILANE ESTER DERIVATIVES

Lucio Pellacani, Maurizio D'Auria, Raffaele Saladin

Organocatalytic Formation of Quaternary Stereocenters

This work reviews the authors' choice of recently published papers where at least one asymmetric quaternary stereocenter has been formed via organocatalysis. The scope and limitations of the reactions are highlighted 90% ee and >10 : 1 dr

An Organocatalytic Approach to the Synthesis of Six-Membered Heterocycles

"""In the last few years, the new era of organocatalysis opened up an effective and efficient way to high yielding metal free, enantio- and diastereoselective reactions leading to six-membered heterocycles. This review provides an overview of the current achievements in the organocatalytic synthesis of these crucial building blocks. Ranging from hetero-Diels-Alder to cycloadditions, from one step cyclizations to cascade reactions, recent results offer new powerful tools to obtain six membered heterocycles with facile procedures in high yields and stereoselection, often leading to many new stereogenic centres in a single reaction. The total syntheses of natural products having heterocyclic ring formation as crucial stage, are also reported. When available, alternative supported organocatalysts have been examined""

Preparazione Stereoselettiva di Derivati di beta-Ammino Acidi beta,beta-Disostituiti

(Comunicazione Poster

Asymmetric Organocatalytic Aziridination: Recent Advances

Aziridines, the nitrogen counterparts of epoxides, are among the most challenging and intriguing heterocycles in organic chemistry since they not only represent the endpoints of several total syntheses as common scaffolds in natural products but also act as crucial precursors of complex molecules. The present review provides a brief overview of aziridine derivatives as well as the authors’ choice of published papers that highlight recent enhancements concerning asymmetric organocatalytic strategies involved in aziridination reactions