The indolino[2,1-b]oxazolidine derivatives for the development of multi-addressable molecular systems

International audienc

Stable Photoinduced Separated Charge State in Viologen Halometallates: Some Key Parameters

With the aim to define key parameters causing the photochromic properties of (MV)[Bi2Cl8] and (MV)(4)[Bi6Cl26] (MV2+, methylviologen; 1,1-dimethyl-4,4-bipyridinium), the effects of substituting Bi by Sb, Cl by Br, or MV2+ by MOV2+ (1,1-dimethoxy-4,4-bipyridinium) or MeMOV2+ (1-methyl-1-methoxy-4,4-bipyridinium) on the photoinduced charge transfer properties of such viologen halometallates are explored. It appears that only salts containing chlorobismuthate anions undergo a color change upon UV irradiation and that the nature of viologen entities has a key role in the process. We also suggest that a key parameter for observing the stable photoinduced separated charge state in chlorobismuthate viologen hybrids is a high chloride/viologen ratio, rather than the size of the anionic oligomer, as observed in the previously reported unique series (MV)((2n+2)/2)[Bi2nCl8n+2]

Photon-Working SwitchesProperties and Applications of Indolinooxazolidines as Photo-, Electro-, and Acidochromic Units

The aim of this chapter was to introduce the readers to indolinooxazolidines (IndOxa), a new family of molecular switches. First, in a short historical account their evolution is followed from their first appearance in the 1970s until today. The second section concentrates on the general structural features of the indolinooxazolidine motif, which are closely related to those of the spiropyrans. In the core of their chemistry lies the oxazolidine ring opening that is discussed in the following. Owing to the facility of the very same ring opening, they show chromophoric properties and can be addressed using different stimuli, such as light irradiation, change in electrical potential and pH. For this reason, the last three sections are devoted to provide a general understanding on their photo-, electro-, and acidochromic properties

Relationship Between Clostridium difficile Testing Method, Antibiotic Treatment, and Clinical Symptoms

Clostridium difficile (C. difficile) infection is a leading cause of morbidity and mortality in the United States, making the infection a top public health priority. Early and accurate identification of disease is a critical factor in successful management, including clinical symptomology. The testing methods for C. difficile have improved in efficiency and sensitivity, which potentially causes over- or underprescribing behavior. Guided by the symbolic theory, the purpose of this study was to examine the association between C. difficile testing method by case year (2015 and 2018) and antibiotic treatment with the potential moderation of clinical symptoms. The secondary correlational analysis included patients admitted to a large suburban hospital with a positive test for C. difficile in 2015 and 2018 (N = 509). The relationship between the study predictor (case year), dependent variable (antibiotic treatment), and moderator (symptom) was analyzed using binomial logistic regression. Antibiotics showed a significant association with the case year (OR = 1.889) and no significant moderation with the addition of symptoms (OR = 1.303). Health care providers may find these findings useful in standardizing treatment of C. difficile through the implementation of additions to clinical algorithms, resulting in positive social change. Increased education, and policy, through antibiotic-resistant organism reduction, increased antimicrobial stewardship, and increased patient safety, may have social implications

Amino Acid Derivatives of Tetrathiafulvalene and Their N-H center dot center dot center dot O Peptide Bond Dipoles-Templated Solid State Assemblies

We report on a series of amino acid derivatives of tetrathiafulvalene as well as on the structure-directing abilities of their peptide residues in the crystalline solid state to stabilize patterns of interactions such as beta strands and sheet motifs. Characteristic hydrogen-bonding motifs are indeed identified within ethylenedithiotetrathiafulvalene (EDT-TTF) and dimethyltetrathiafulvalene (Me-2-TTF) based compounds 1-5. Esters 1-3 contain hydrogen-bond acceptors, namely carbonyl groups, as well as one strong (NH) and one weak (C-sp(2)-H) hydrogen-bond donor. In addition to the hydrogen-bonded sets of ester derivatives, acids 4 and 5 present the carboxylic acid moiety, which acts as both a hydrogen-bond donor and acceptor. EDT-TTF-CO-GlyOH has been previously used to afford a new type of hydrogen-bonded acid/zwitterion (1:1) hybrid admixture of redox peptidics

Silica-Mediated Synthesis of Indolinooxazolidine-Based Molecular Switches

A novel and convenient method for the synthesis of photochromic compounds is reported here. It is based on the use of commercially available untreated silica, as an efficient catalyst to perform the condensation between indolinooxazolidine derivatives and aromatic aldehydes under solvent-free conditions. The scope and limitations of this transformation were investigated and several novel photochromic indolinooxazolidines were synthesized. This methodology can also be applied to the synthesis of other photoactive compounds such as spiropyrans or spirooxazines. According to our working protocol the reaction did not require any solvent or additional reagents and gave the products within 10 min in isolated yields of up to 90%

The stepwise oxidation of indolino[2,1-b]oxazolidine derivatives

This work presents an original strategy to modulate the electrochemical properties of the indolino[2,1-b]oxazolidine core appropriately substituted in position 5 (para-substitution of the phenyl ring) by acceptor or donor groups (CHO, OMe, Me, F, H, Cl, Br). Supported by spectroelectrochemical experiments and confronted to electrochemical simulations, the stepwise oxidation of indolino[2,1-b]oxazolidine derivatives involves an electrochemical mechanism which depends on the para-substitution of the phenyl ring and leads to either the formation of a stable radical cation, the opening of the oxazolidine ring or an irreversible aryl C-C coupling

Synthesis and evaluation of naphthoic acid derivatives as fluorescent probes to screen advanced glycation end-products breakers

Advanced glycation end-products, namely AGEs, are involved in the pathogenesis of numerous diseases. If AGEs inhibitors are well-known, only few products are described as compounds able to destroy those deleterious products. In this work, we describe naphthoic acid derivatives, particularly 1-(naphthalen-1-yl)propane-1,2-dione 9, allowing the simple and rapid detection of AGEs breakers using a 96-well microplate fluorescence assay. Since the inaugurate publication about AGEs breakers whose activity was demonstrated using HPLC analysis, this work proposes the first assay suitable for automated and high throughput screening of AGEs breakers