Sustainable Approaches for the Synthesis of Nitrogen and Oxygen Functionalized Small Organic Molecules.

Two important categories of O-functionalized compounds are O-heterocycles and polyphenols. All these two categories are widespread in nature and present as scaffold in many natural compounds. Well-known examples are sugar core of DNA and RNA, Quercitin, Curcumin, Vitamins (especially E and C), Taxol, Dynemicin, and many others; and their biological applications are well-known too (anti-inflammatory, anti- oxidant, antiviral, anticancer and others). The synthesis of O-functionalized compounds has been always an important and crucial research field of organic synthesis and nowadays many methods are reported in literature.[20 - 25] This first chapter is focused on two different projects related together by the O- functionalization of final target products and by the very important biological, antiviral, therapeutical applications that they found or they could find. The aim of first section is to synthesize LNA-Adenosine derivative by linear strategy. The LNA (Locked Nucleic Acid) are very important Nucleic Acid analogues, synthesized for the first time by Iminashi et al. [26] and Wengel et al.[27] respectively in 1997 and 1998, in an independently way. These analogues are very important due to the antisense, antigene, antiviral, and many others bio-applications, overcoming some problems related to employment of not-modified nucleic acids. The topic of the second chapter is the synthesis of a new phenolic compound with potential antiviral activity against Sars-CoV-2. Our purpose is to obtain this new polyphenol through the combination of two intermediates, an alkyne and an aldehyde, obtained from two commercial, cheap and easy available starting material. Natural and synthetic heterocycles has greatly attracted the interest of scientits because of their widely applications in many fields of science: biological, pharmaceutical, synthetical and industrial applications (plastic, solvents, cosmetics, vulcanization accelerators, etc.)[175] Among them, N-heterocycles have always constituted an important synthetic target due to the pharmaceutical and biological superior properties than non-nitrogen containing cycles[175b] and for their wide distribution in many natural bioactive compounds (such as alkaloids).[176] From a statistical analyses it emerges that 59% of FDA-approved small molecule drugs contain at least one of N-heterocycles moieties in which the six- and five-membered are the size-cycles more diffused, although three-, four-, bicyclic-, macrocyclic N-heterocycle scaffolds are present.[177] Moreover, this last class of compounds have shown useful, not only in medicinal fields, but also in metallurgical applications thanks by their ability to chelate first-row transition metals like Mn(II), Zn(II), Fe(II), Cu(II) and for other industrial applications.[178] Nowadays many scientist are focusing on the development of new sustainable synthetic approaches for this class of compounds[175a] given their potential applicability in many science and everyday life aspects. New approaches consist in employment of UV-light (the most sustainable reactions induces, largely applied in organic synthesis); [179] employment of less toxic, environmentally benign and less expensive Lewis Acid catalysts like Zn, Fe, Cu, Ni cores (minimization of waste, time consuming, improved selectivity, often they allow to build complicated structures under mild conditions);[175a], [180] performing the reaction under microwave irradiations;[181] through multicomponent reactions (which implicate time saving, avoid the separation and purification of intermediates, atom- efficent reactions, type reactions used also for the synthesis of pharmaceuticals, drugs and compounds by stereoselective routes);[182] employment of less toxic solvents like ionic liquid;[183] just to cite few examples. This chapter is divided in three sections in which three different N-heterocycle scaffolds are synthesized by new sustainable approaches. The first section is focused on the synthesis of an aza-macrocycle with the purpose to overcome some problems related to the synthesis and enhanced some aspects making them more suitable for green aspects that rule the scientific world today. The aim of second section is the synthesis of a six-membered N-heterocycles (1,2- dihydropyridines) through polycondensation of acyclic precursor using a not expensive and low-toxic Lewis acid like CeCl3 .7H2O, emphasizing kinetic, thermodynamic aspects of condensation process. The last section is divided in two more parts in which: the first one focuses on the synthesis of tetrahydro-β-carboline (very important bioactive compound) using not harmful Brønsted acids like graphene oxide and Amberlyst-15® through the Pictect- Spengler reaction; the second part, instead, reports the first results about the development of a new multi-component Pictect-Spengler reaction promoted by Ce(III)-Lewis Acid for the synthesis of N-substituted tetrahydro-β-carboline

Effects of non-linear rheology on the electrospinning process: a model study

We develop an analytical bead-spring model to investigate the role of non-linear rheology on the dynamics of electrified jets in the early stage of the electrospinning process. Qualitative arguments, parameter studies as well as numerical simulations, show that the elongation of the charged jet filament is significantly reduced in the presence of a non-zero yield stress. This may have beneficial implications for the optimal design of future electrospinning experiments

Potenza e adattabilit

My essay aims to demonstrate that Neoliberalism exercises its art of government on forms of life turning their potentiality into adaptability. According with one of most influential reference thinker of Neoliberalism, Friedrich von Hayek, the spontaneous order of the market requests the constant adaptation of individuals to circumstances of which no one can be aware and can master. However, such adaptability – that could come from a certain negative philosophical anthropology – is the reverse side of the same potentiality theorized by authors of Italian Thought like Agamben, Esposito and exponents of Post-Operaism. The paper aims to focus the condition for which such conversion of potentiality into adaptability is prevented

Hic sunt leones. Confine/Frontiera: Genealogia politica di un dispositivo spaziale

“Border” and “Frontier” are configurations that name differently the spatial dispositif that regulates and organize the relationship between inside and outside, between citizens and foreigners. My essay aims to define each one of these spatial categories on the basis of their respective ontological, political, geographical meaning and function. Starting from their original definition in ancient Rome, I analyze their function through the political forms (City, Empire, State) they determinated during the ancient and modern history. The transformations that the inclusion/exclusion dispositif has undergone in the course of history on a political, legal and geographical level —evident if one considers how these have influenced the configuration of cartographic maps— are reflected in the determination of subjectivity. It is therefore possible to define a border subject and a frontier subject if their subjectification proceeds from the border disposif or from the frontier dispositif. On a geopolitical level, the formation of the modern state has undoubtedly led to the dominance of the border dispositif from a political and legal point of view. However, this has not led to the frontier being limited to a fundamentally symbolic level. Rather, the frontier has been defined as a dispositif whose effectiveness can be measured in the medical and economic sphere, since the era of the emergence of the political form of the state in Europe. Moreover, the American experience of the frontier in the formation of the United States reveals the peculiarity of the frontier dispositif even in modern times. Nowadays more than in the past, it is difficult to identify and distinguish between border and frontier subject. European citizens themselves feel in their individual lives that the legal and political guarantees given to them by that citizenship which identifies them as border subjects are called into question —for example within the global labour market— by their potentially being frontier subjects

La politica dei mezzi puri. Sui paragrafi 10 e 11 di Sulla critica della violenza di Walter Benjamin

Questo articolo è incentrato sull’analisi dei paragrafi 10 e 11 di Sulla critica della violenzadi Walter Benjamin. In particolare, si sofferma su due aspetti: la funzione della polizia nell’ordinamento giuridico dello Stato e la “politica dei mezzi puri”. Benjamin considera sia la polizia che la politica dei mezzi puri come appartenenti al “regno dei mezzi”, ma rappresentano due configurazioni alternative di politica. Lo Stato di polizia esemplifica l’arte di governo che si produce quando “lo stato di eccezione è la regola”, cioè quando la paura della violenza costantemente riprodotta svolge una funzione disciplinare. Al contrario, la politica dei mezzi puri indica la possibilità di una politicizzazione degli esseri umani sulla scorta di disposizioni soggettive diverse se non alternative a quella paura che la tradizionecontrattualista della politica moderna ha assunto come movente fondamentale pergiustificare l’istituzione dell’ordinamento giuridico dello Stato

Gubernamentalidad, hegemonía, inmunopolítica: Foucault, Gramsci, Esposito

En una lección de su curso en el Collège de France en 1978-1979, Naissance de la biopolitique, Foucault plantea la cuestión de si existe una “gubernamentalidad socialista” que pueda representar una alternativa a la gubernamentalidad neoliberal. Su respuesta es negativa, ya que cree que el socialismo en ese momento consiste fundamentalmente en una “hiperadministración del Estado”, ignorando así una racionalidad de gobierno que contemple las conductas sociales. La misma cuestión, la relación entre movimientos sociales y Estado, es una constante fundamental dentro de la Teoría Italiana; se consideran dos formulaciones en particular: la “hegemonía” de Antonio Gramsci y la más reciente de “práctica instituyente” de Roberto Esposito, que repiensa la biopolítica como “inmunopolítica”

Metal-Promoted Heterocyclization: A Heterosynthetic Approach to Face a Pandemic Crisis

The outbreak of SARS-CoV-2 has drastically changed our everyday life and the life of scientists from all over the world. In the last year, the scientific community has faced this worldwide threat using any tool available in order to find an effective response. The recent formulation, production, and ongoing administration of vaccines represent a starting point in the battle against SARS-CoV-2, but they cannot be the only aid available. In this regard, the use of drugs capable to mitigate and fight the virus is a crucial aspect of the pharmacological strategy. Among the plethora of approved drugs, a consistent element is a heterocyclic framework inside its skeleton. Heterocycles have played a pivotal role for decades in the pharmaceutical industry due to their high bioactivity derived from anticancer, antiviral, and anti-inflammatory capabilities. In this context, the development of new performing and sustainable synthetic strategies to obtain heterocyclic molecules has become a key focus of scientists. In this review, we present the recent trends in metal-promoted heterocyclization, and we focus our attention on the construction of heterocycles associated with the skeleton of drugs targeting SARS-CoV-2 coronavirus

The Austerity of the Commons: A Struggle for the Essential

In a precarious context induced by a struggle for the essential, one term has re-emerged as indispensable, providing many of us with a new sense of direction, creation and sharing, and ultimately, like a boomerang, assuming the ‘austere’ dignity of that which cannot be renounced: the commons