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POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) is a rare paraneoplastic disorder due to an underlying plasma cell dyscrasia. The diagnosis of POEMS syndrome requires a chronic polyneuropathy and a monoclonal lambda plasma cell-proliferative disorder (mandatory criteria), and various systematic symptoms such as sclerotic bone lesions, Castleman's disease, organomegaly, endocrinopathy, skin changes, papilloedema and biological abnormalities such as elevated vascular endothelial growth factor (VEGF), thrombocytosis or polycythaemia. We describe an observation of a patient with recurrent thrombosis with thrombocytosis that, after excluding a myeloproliferative neoplasm, proved to be due to POEMS syndrome. This case is unusual compared to the foreground thrombotic symptomatology. POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) is a rare multi-systematic paraneoplastic disorder due to an underlying plasma cell disorder. The diagnosis of POEMS syndrome requires the presence of both mandatory criteria (a chronic polyneuropathy and a monoclonal plasma cell-proliferative disorder, always lambda restricted); at least one major (among sclerotic bone lesions, Castleman's disease, elevated VEGF (vascular endothelial growth factor)) and one minor criterion (among organomegaly, endocrinopathy, skin changes (haemangiomas, hypertrichosis, hyperpigmentation), papilloedema and thrombocytosis or polycythaemia. We describe an unusual observation of a young patient with recurrent thrombosis with thrombocytosis that, after excluding a myeloproliferative neoplasm, proved to be due to POEMS syndrome.

Resume L’interpretation medicale d’un hemogramme necessite un respect des exigences pre-analytiques et une maitrise par le biologiste et le technicien de laboratoire des differentes technologies analytiques a sa disposition ainsi qu’une veille bibliographique reguliere. Des problemes pre-analytiques, interferences ou limites technologiques peuvent conduire a des resultats bruts errones et a une mauvaise interpretation de l’hemogramme. Cet article presente differents pieges a eviter pour l’analyse des parametres erythrocytaires selon notre experience avec les analyseurs d’hematologie de la serie XN (Sysmex).

Recent works in side-channel analysis have been fully relying on training classification models to recover sensitive information from traces. However, the knowledge of an attacker or an evaluator is not taken into account and poorly captured by solely training a classifier on signals. This paper proposes to inject prior information in preprocessing and classification in order to increase the performance of side-channel attacks (SCA). First we propose to use the Wavelet Scattering Transform, recently proposed by Mallat, for mapping traces into a time-frequency space which is stable under small translation and diffeomorphism. That way, we address the issues of desynchronization and deformation generally present in signals for SCA. The second part of our paper extends the canonical attacks over byte and Hamming weight by introducing a more general attack. Classifiers are trained on different labelings of the sensitive variable and combined by minimizing a cross-entropy criterion so as to find the best labeling strategy. With these two key ideas, we successfully increase the performance of Template Attacks on artificially desynchronized traces and signals from a jitter-protected implementation.

International audience; The CHIMACTIV website (http://chimactiv.agroparistech.fr/) offers open educational resources related to analytical chemistry. It addresses a frequently encountered pedagogical issue: How can we encourage students to be more involved in learning during their courses (and especially during lab work) as well as provide a deeper teacher–learner interaction during these sessions? With 30 digital bilingual (English/French) sections divided into 5 topics (safety in a chemistry lab, basics of manipulation, food analysis, drug analysis, and familiarity with experimental methodologies), CHIMACTIV offers a great variety of media (scientific content, short videos, interactive diagrams, pictures, games, quizzes, and exercises) which are responsive to all formats of the digital medium (computer, tablet, smartphone). Depending on their educational objectives and their students’ curricula, teachers can guide students toward the appropriate resources to strengthen their backgrounds, build new scientific understanding, or analyze data. These digital resources may be consulted before, during, or after class and/or lab sessions, and they are ideal for students aiming to self-train, for trainees in research laboratories, as well as for professionals working in a sector related to chemical analysis.

International audience; The CHIMACTIV website offers open access, digital educational resources related to chemical analysis. It tacklesa teaching problematic: how could we encourage students to be more involved in learning during teachingcourses (especially lab work) and provide deeper teacher-learner interactions during the sessions? With thirtyautonomous bilingual (English/French) sheets classified in five themes, CHIMACTIV offers a great variety of media(scientific content, short videos, interactive schemes, pictures, games, quizzes and exercises) with responsivenature allowing their consultation on any support (computer, tablet, smartphone). Depending on theireducational objectives, the professors can guide the students towards the appropriate resources to consultbefore, during or after class and lab sessions, in order to revise prerequisites, build new scientific backgroundor analyze data. These digital resources are also very useful for trainees in research labs as well as for professionalsworking in a sector linked to chemical analysis.; Le site CHIMACTIV offre des ressources pédagogiques numériques libres d’accès dans le domaine de l’analysechimique. Il répond à une préoccupation pédagogique : optimiser le temps d’apprentissage en présentiel (notam-ment en séances expérimentales) et enrichir les interactions apprenants-enseignants. Organisé en cinq thèmes ettrente fiches (en version bilingue français/anglais), CHIMACTIV offre une grande diversité de ressources numériques(contenus théoriques, schémas animés, courtes vidéos, exercices, quiz...), adaptables au support de lecture (ordina-teur, tablette, smartphone). Selon leur intention pédagogique, les enseignants peuvent orienter les élèves vers lesressources à consulter avant, pendant ou après des séances de cours, TD ou TP, afin de réviser des prérequis, acqué-rir de nouvelles connaissances ou interpréter des résultats. Ces ressources sont également utiles pour des stagiairesen laboratoire de recherche ainsi que pour des professionnels évoluant dans un secteur lié à l’analyse chimique.

BackgroundMalaria is a potentially severe disease affecting nearly 200 million people per year. Early detection of the parasite even in unsuspected patients remains the challenging aim for effective patient care. Automated complete blood counts that are usually performed for any febrile patient might represent a tool to ascertain malaria infection.AimsTo evaluate the ability of the new generation of the Sysmex hematology analyzer (XN-series) to detect malaria.MethodsWe retrospectively studied 100 blood samples performed with the recent Sysmex XN analyzer that were positive forPlasmodiumand explored its ability to detect the parasite. 100 samples from patients uninfected by malaria were used as control group.ResultsSpecific abnormalities such as additional events in the mature neutrophil/eosinophil area of the white blood cells differential (WDF) scattergram were noted for 1.1% ofPlasmodium falciparumsamples and 56.2% of otherPlasmodiumspecies samples. Mature parasite stages (schizonts or gametocytes) were observed on blood smears among those samples. WDF scattergrams were able to detect 80.0% (12/15) ofPlasmodiummature stages. Furthermore, the differential in white blood counts between WDF and white cell nucleated (WNR) channels was a predictive signal ofPlasmodiummature stages in 73.3% (11/15) of samples and may be explained by a differential destruction of particles with the analyzer reagent.ConclusionAssociated to thrombocytopaenia, a Sysmex XNPlasmodiumpattern may represent a useful warning forPlasmodiumdetection in unsuspected patients, particularly when mature parasite stages are present.

AimThe aim was to assess the flagging performance of Sysmex XN-10 haematology analyser for malaria detection through the parasitic red blood cell (‘pRBC’) alarm.MethodsWe retrospectively studied 584 blood samples performed on the Sysmex XN-10 analyser that were tested for malaria. Sensitivity, specificity, positive and negative predictive values, and prevalence were established for the pRBC alarm.ResultsSensitivity, specificity, and positive and negative predictive values for the pRBC flag were 7.8%, 100%, 100% and 87.7%, respectively. The prevalence of pRBC flag of 0.026% in the overall population was significantly different from the prevalence of 1.027% in the population tested for malaria.ConclusionsConsidering the excellent specificity and the low prevalence of the flag in the overall population, we suggest, in case of the presence of pRBC flag, the implementation of a rapid review of the blood smear looking for Plasmodium, mostly if the patient had fever and had not been tested for malaria.

Resume Cette etude rapporte une observation cytologique rare : la presence d’inclusions vertes-turquoises intra- cytoplasmiques dans des polynucleaires neutrophiles et des monocytes sur un frottis sanguin. Ces inclusions ont ete observees transitoirement chez deux patients hospitalises en reanimation pour choc septique complique d’une defaillance multi-viscerale ayant conduit au deces. Leur apparition a coincide avec l’augmentation du taux de transaminases hepatiques liee a une necrose hepatique severe. De telles inclusions ont rarement ete observees a ce jour ; elles ont ete decrites dans des contextes cliniques similaires avec un risque eleve de mortalite. Ces inclusions inhabituelles, en nombre variable dans les leucocytes, ne doivent pas etre confondues avec des corps de Dohle et doivent etre connues des cytologistes.

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The synthesis, photophysical and electrochemical properties and their interplay as well as theoretical calculations studies of newly designed fluorescent and electroactive derivatives are described. These molecules are composed of two fluorophores: one triphenylamine, electron-rich unit, and one tetrazine, electron-poor unit, connected by two different links. While in the neutral state the bichromophores are not fluorescent, due to a photoinduced electron transfer from the triphenylamine unit to the tetrazine unit, the fluorescence is restored in the oxidative state (oxidation of the triphenylamine moiety).

This paper reports the synthesis and the linear and non-linear absorption properties of a series of new tetrazine-based D–π–A–π–D and D–π–A type dyes. In these derivatives, a central tetrazine core was connected with one or two terminal triphenylamine moiety(ies) via various π-conjugated spacers. These compounds were efficiently synthesized by Stille or Suzuki–Miyaura cross-coupling as a key step. Their photophysical properties, including one-photon absorption and two-photon absorption (2PA), were investigated with special attention to structure–property relationships. Large 2PA cross-sections (>800 GM) of these tetrazine dyes were evaluated by open aperture z-scan and non-degenerate 2PA techniques. The strong 2PA of these molecules is attributed to the extended π system and to the enhanced intramolecular charge transfer between the triphenylamine donor and the center tetrazine acceptor.

Malaria is a potentially severe disease affecting nearly 200 million people per year. Early detection of the parasite even in unsuspected patients remains the challenging aim for effective patient care. Automated complete blood counts that are usually performed for any febrile patient might represent a tool to ascertain malaria infection.To evaluate the ability of the new generation of the Sysmex hematology analyzer (XN-series) to detect malaria.We retrospectively studied 100 blood samples performed with the recent Sysmex XN analyzer that were positive forSpecific abnormalities such as additional events in the mature neutrophil/eosinophil area of the white blood cells differential (WDF) scattergram were noted for 1.1% ofAssociated to thrombocytopaenia, a Sysmex XN

The study of the chemical and electrochemical fluorescence switching properties of a family of substituted triphenylamine derivatives is reported. First of all, the synthesis of a family of six compounds is described. They are characterized by electrochemistry, UV-vis and fluorescence spectroscopy and spectroelectrochemistry. Theoretical calculations were performed in order to corroborate the experimental results. While these compounds emit blue to green light under UV irradiation with a large quantum yield (37%) in the case of one molecule, the fluorescence intensity is quenched upon oxidation. The fluorescence behavior can be switched between the strong fluorescent (neutral) state and the non-fluorescent (oxidized) state with a high contrast (around 1500 for the fluorescence intensity for one of these molecules). Furthermore, the chromatic contrast of three of these molecules reaches 70% that can be important for further applications.

Original new electroactive dyads have been prepared, featuring two different electroactive groups, namely a triphenylamine and a tetrazine, linked through various linkers. We describe here the synthesis, the electrochemical and some photophysical properties of these molecules which are composed of two separate components, one triphenylamine, electron-rich unit, and one tetrazine, electron-poor unit. The electroactivity of both moieties of the molecule is quite apparent in each case and potentials depend upon the type of linker between the groups.

True Random Number Generators have many uses, in particular they play a key role in security applications and cryptographic algorithms. Our interest lies in the quality of their generated random numbers. More specifically, for such utilizations, a slight deviation of the numbers from a "perfect" behavior can have disastrous consequences. It is then necessary to devise schemes for the testing of these generators in order to detect non-random properties of their numbers. Moreover, one should consider them from an attacker point of view and use any means to try to perturbate their good functionnality. In this article we describe such experiments and several standard statistical tools for the generators testing. We also present experimental results obtained through the study of a generator embedded in a processor in order to illustrate our methodology. We show that its pertubation leads to the apparition of dangerous deviations in its numbers distribution.

Original new fluorescent and electroactive compounds have been prepared, which feature two different fluorescent groups linked through an oxygen atom spacer. We describe here the synthesis, photophysical and electrochemical properties and their interplay, and our theoretical calculations. These molecules are composed of two fluorophores, an electron-rich triphenylamine unit and an electron-poor tetrazine unit. Although the bichromophores are not fluorescent in the neutral state due to a photoinduced electron transfer from the triphenylamine unit to the tetrazine unit, one can restore the fluorescence by oxydation of the triphenylamine moiety. Thus, a redox-fluorescent switch has been realized.

New dyes based on BODIPY and tetrazine fluorophores connected through a phenyl spacer have been synthesized and their absorption, emission and electrochemical properties characterized. BODIPY can be reversibly oxidized into a stable cation radical whereas tetrazine can be reduced to a stable anion radical. The electrochemical and absorption studies demonstrate that both fluorophores behave independently. The bichromophoric compounds show an expected very weak emission by the BODIPY core that is quenched by the phenoxytetrazine mainly through energy transfer. DFT calculations and spectroelectrochemistry experiments demonstrate that photoinduced electron transfer and energy transfer remain possible when the tetrazine moiety is reduced electrochemically, which prevents switching on of the fluorescence of the BODIPY unit.

International audience; Four new hindered boron-dipyrromethene (BODIPY) dyes have been engineered and synthesized by modification of the pyrrole substituents. The chromophores were designed to shift their absorption and emission wavelengths to the red and to show quantitative emission in solid amorphous deposits. [2.2]Paracyclophane (PcP) was grafted on the BODIPY core as well as alkyl chains of various length to force the molecules away one from each other and prevent π-π stacking. The optical spectroscopic and electrochemical properties in solution are presented. Absorption, emission and FLIM were done on drop-casted films of the fluorophores. The addition of alkyl substituents (-Me, -Et, n-Pr) next to the PcP group clearly affects the emission properties in solid state since the dyes display sharper emission bands than in solution and their relative fluorescence quantum yield increases with the number of carbons in the alkyl chain. Fluorescence lifetime images analysis reveals complex decay profiles. Quite a fair description is given by a biexponential fit: the short component is attributed to aggregates and the long component to monomer-like molecules. This population shows a shorter lifetime (2-3.9 ns) compared to solution (6 ns) due to a quenching by aggregates. This quenching is decreasing as the number of carbons on the alkyl side chain is increasing. The combination of a PcP group next to a n-Pr group on a BODIPY is a good combination to get an excellent fluorophore in the solid state.

Trimesityl-BODIPY (TMB), a new derivative of 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene belonging to fluores-cent nanostructures series, was synthesized from the corresponding pyrrole by the Trofimov reaction. This reaction was also employed to obtain 2-[2.2]paracyclophanylpyrrole from 5-acetyl[2.2]-paracyclophane. The spectral properties of TMB have been investigated in dichloromethane, nanolatex (polystyrene) films prepared by rapid solvent evaporation, and microcrystals. Comparative analysis of TMB properties with those of mesityl-BODIPY (MB) was performed. TMB was prepared to minimize π-π interactions in order to preserve luminescence in the aggregate state. Both fluorophores were shown to form fluorescing aggregates in the amorphous state (film). Fluorescence spectra (extinction and lifetime) were also studied. In crystal, MB shows a weaker fluorescence, while TMB behaves as a single fluorescing aggregate with a lifetime of 9.5 ns.

We report here the design of two sets of multifluorophoric silica nanoparticles, observing unprecedented efficiencies in the energy-transfer processes among the doping dyes. These nanomaterials show a very high overall sensitization, allowing under a single wavelength excitation to obtain many different colors (one per nanoparticle) in emission with negligible crosstalk. Moreover, each particle can present very large and tunable pseudo-Stokes shifts (up to 435 nm), a very high brightness even exciting the bluest donor, and a negligible residual emission intensity from all donor dyes. All these features, combined with colloidal stability and synthetic method reliability, make these multicomponent nanoparticles very promising for multiplex analysis and for all the diagnostic techniques requiring high sensitivity associated with a large Stokes shift.

Novel 3-O-[1,2;5,6-di-O-isopropylidene-alpha-D-glucofuranose] and 3-O-[D-glucose] derivatives with an iminodiacetate (N,O,O), a histidinate, and an N-(acetetyl)picolylamine (N,N,O) chelating system for tridentate coordination of the organometallic M(CO)(3)-fragment (M = Tc, Re) have been prepared. The chelates were introduced and assembled through reductive amination starting from 3-O-[1,2;5,6-di-O-isopropylidene-alpha-D-glucofuranose]-acetaldehyde. After deprotection, the pyranose derivatives were reacted with the precursor [NEt(4)](2)[ReBr(3)(CO)(3)] to afford the corresponding organometallic complexes in yields between 54% and 94%. The NMR, MS, and IR analyses corroborated the tridentate coordination of the organometallic metal center exclusively via the synthetic chelates. In the case of the N-(acetyl)picolylamine derivative, the coordinative properties were further confirmed by X-ray structure analysis of the first Re(CO)(3)-D-glucofuranose complex. All glucose complexes unveiled good stability and solubility in organic and aqueous media.

The reaction of E -ethylmesitylketoxime with acetylene in the system KOH/DMSO (the Trofimov reaction) (70–74 °C, 3 h, atmosphere pressure) affords 2-mesityl-3-methylpyrrole (23%), 2-mesityl-3-methyl-1-vinylpyrrole (8%), Z - (5%) and E - (2%) isomers of O -vinylethylmesitylketoxime. Initial ethylmesitylketoxime was prepared in two ways: via very slow oximation of ethylmesitylketone in 30% yield after 8 months, and, more efficiently, by oximation of ethylmesitylketimine hydrochloride derived from bromomesitylene in several steps. 2-Mesityl-3-methylpyrrole was used for the synthesis of 4,4-difluoro-2,6-dimethyl-3,5,8-trimesityl-4-bora-3a,4a-diaza- s -indacene with mesityl substituents having hindered internal rotation and preventing π-stacking at high concentrations. The latter factor enables the fluorescence of crystals of the prepared BODIPY, a feature that was not previously documented for such molecules.

A series of nine organometallic technetium-99m and rhenium complexes of glucose are presented and characterized in vitro regarding their potential as surrogates of [18F]-2-fluoro-desoxy glucose ([18F]-FDG). The glucose derivatives are functionalized at positions C-1, C-2, C-3, and C-6. Different spacer lengths and chelating systems have been introduced at these sites. For the (radio)labeling, the organometallic precursors [99mTc(H2O)3(CO)3]+ and [ReBr3(CO)3](2-) respectively have been used. The resulting complexes have been characterized chemically and radiochemically. The formation of uniform products has been observed on the macroscopic (Re) and no-carrier-added level (99mTc). The Tc-99m complexes revealed good inertness against ligand exchange (Cys and His) and excellent stability in physiological buffered saline as well as in human plasma over a period of 24 h at 37 degrees C. The rhenium complexes have been tested for competitive inhibition of the (yeast) hexokinase. Only for C-2 derivatized glucose complexes with extended spacer functionalities Ki values in the millimolar and sub-millimolar range have been observed. In silico molecular docking experiments supported these experimental findings. However, the competitive inhibitors are not recognized as a pseudosubstrate of hexokinase. The cellular uptake of all 99mTc-complexes into HT-29 colon carcinoma cells via Glut1 was generally low and unspecific independent of the position at the hexose ring, the chelating systems, or the overall charge of the corresponding metal complexes. The current results seem to preclude the use of these compounds as [18F]-FDG surrogates primarily due to the low cellular uptake via Glut1.

The folate receptor (FR) is a high affinity membrane protein which is overexpressed on a wide variety of tumor cells, but highly restricted in normal tissues. Therefore folate derivatives labeled with short living isotopes such as 99mTc (γ, t1/2 = 6 h) or 188Re (β−, t1/2 = 17 h) could be used for tumor diagnosis and therapy. In this respect there is a great interest to develop organometallic technetium(I) and rhenium(I) modified folate radiopharmaceuticals. For this purpose folic acid was functionalized with a tridentate picolylamine monoacetic acid chelating system. The chelating system was selectively coupled via an aminohexane spacer to the γ- or α-carboxyl group of the glutamate moiety of folic acid to obtain the corresponding γ- or α-folate derivative or – if directly attached to pteroic acid – the pteroate derivative. The derivatives were reacted with the precursor [M(OH2)3(CO)3]+ (M = 99mTc, Re) to form uniform organometallic folate complexes under mild reaction conditions. All compounds were chemically characterized by means of NMR, MS, IR and HPLC. The determination of the IC50-values for the PAMA-γ-folate derivative (100 nM) and the corresponding organometallic rhenium complex (110 nM) proved retained receptor binding properties. The radiolabeling with [99mTc(OH2)3(CO)3]+ was achieved in excellent yield (>95%) at low ligand concentration (10−4 M). The cell binding (>45% of total activity) and internalization (>15% of total activity) of all 99mTc-complexes was very high and specificity for the FR was proved by their complete displacement with excess folic acid. The 99mTc-complexes were positively tested for their plasma stability and for the absence of binding to plasma proteins.

(±)-17-Methylcamptothecins (29) were synthesized from the heteroyohimbane ajmalicine (5) through sequential oxidation steps and E-ring functionalization. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

A general synthetic approach for potent tridentate, bifunctional chelating agent (BFCA) for the [M(CO)(3)](+) fragment (M = (99g)Tc, (99m)Tc, and Re) has been elaborated. The strategy allows the facile preparation of BFCA with a pendent amino or carboxylic acid functionality for coupling to peptides and proteins via formation of an amide bond. [(5-amino-pentyl)-pyridin-2-yl-methyl-amino]-acetic acid (APPA) and [pyridin-2-yl-methyl-amino]-diacetic acid (PADA) were synthesized according to this protocol. The BFCA were labeled with the [M(CO)(3)](+) fragment, which resulted in formation of uniform products with a ligand to metal ratio of 1:1. The complexes have been fully characterized by means of mass spectrometry, IR, and NMR ((1)H, (13)C, (99)Tc) spectroscopy. Coordination of the tricarbonyl core with APPA and PADA was exclusively tridentate (via the acid function, the ternary amine, and the pyridine nitrogen). On the n.c.a. level the complexes were almost quantitatively formed (yield90%) at ligand concentrations of 10+/-2 microM (PADA) or 50+/-4 microM (APPA) after 30 min at 70 degrees C. Chromatographic behavior of the (99m)Tc complexes is similar to that of the corresponding (99)Tc/Re complexes suggesting the identical chemical structure. Pharmacokinetic experiments with the (99m)Tc-APPA complex were performed in BALB/c mice and compared with previously published results of the (99m)Tc-PADA complex. The (99m)Tc-APPA complex revealed good clearance from the blood pool (0.29 +/- 0.03% ID after 24h p.i.) and a low uptake in the liver (2.41 +/- 0.14% ID/g), in the kidneys (2.81 +/- 0.12% ID/g) and other tissue and organs.

Six 5′-carboxamide derivatives of 5′-aminothymidine have been synthesized with alkyl chains of various length and a tridentate, imino diacetic acid based chelating system. The thymidine analogues have been reacted with the precursor fac-[M(H2O)3(CO)3]+ (M=99mTc, Re) in aqueous media to form, water-soluble and stable organometallic complexes in good yields. 1H-NMR and IR spectroscopic analyses confirmed in all cases the tridentate complexation of the metal-tricarbonyl fragment exclusively via the tridentate chelates, and no unspecific interaction with other functional groups of the pharmacophor. The organometallic rhenium–nucleoside complexes have been tested in vitro for competitive inhibition of human cytosolic thymidine kinase (hTK1) and herpes simplex virus thymidine kinase type 1 (HSV1-TK). In case of hTK1 it could be observed, that the inhibition capacity of the complexes improved with increasing spacer length. On the other hand, all six complexes showed no or only slight inhibition of the HSV1-TK. The corresponding radioactive technetium-99m complexes have been prepared and challenged for stability in physiological phosphate buffer and human serum albumin at 37 °C for 24 h. Only minor decomposition of the complexes could be detected under these conditions proving the high kinetic inertness and/or stability of these complexes.

Several new oligothiophenes blocked by cyclophane end groups with 2, 3, 4 or 6 thiophene rings in the chain have been prepared and studied by electrochemistry and by UV-visible and fluorescence spectroscopy. Both radical cations and dications are stable, even for the bithiophene compound; besides the stabilization induced by the blocking of the reactive α positions, this strongly suggests electronic connection between the cyclophanes and the oligothiophene chains, especially for the shorter compounds. All the molecules are strongly fluorescent with increasing quantum yields up to 4 thiophene rings. The assumption of a conjugation between the cyclophane end groups and the oligothiophene main chain is also supported by the UV-visible and fluorescence results, since the spectroscopic data correlate well with (n + 2)−1 instead of n−1, with n representing the number of thiophene rings in the oligomer.

Conjugated systems built by connecting one electron-donor triphenylamine to an electron-withdrawing tetrazine have been prepared using various linkers. We describe here the synthesis, the electrochemical properties and some photophysical properties of these molecules, emphasizing the dependence upon the type of linker between the groups and an organic photovoltaic solar cell was prepared with one derivative.

The synthesis, photophysical and electrochemical properties as well as theoretical calculation studies of a newly designed triphenylamine derivative are described. This original compound displays one neutral form, three oxidized forms, and two protonated forms with distinct photophysical characteristics. The interplay of the emission with the protonation or the redox state (electrofluorochromism) has been explored and an on-off-on-off fluorescence switching was observed in the case of oxidation and an on-on-off fluorescence switching in the case of protonation.