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With the aim of finding and characterizing new simple organic molecules (SOM) generating circularly polarized luminescence (CPL), we test here nine [2]paracyclo[2](5,8)‐quinoliphane derivatives, whose circular dichroism (CD) spectra were previously measured at short wavelengths in a study encompassing also OR and VCD (CD in the IR). Completion of the CD spectra is carried out with attention paid to weaker and longer wavelength features. The observed signs of the CPL spectra are compared to the signs of the CD band at the longest wavelength and are found coincident except in two cases. The magnitudes of dissymmetry ratios g in luminescence are of the order 10−3, like the corresponding |g| values for the absorption case. TD‐DFT calculations for the two simplest cases provide details on the molecular orbitals involved in the transitions responsible for the observed signals of these molecules. The calculations allow us to provide also a first explanation of the two observed behaviors of the |glum|/|gabs| ratios. [ABSTRACT FROM AUTHOR]

Research has been conducted on the asymmetric carbon-carbon formation, Diels-Alder, Michael, and aldol reactions. The synthesis of the planar chiral 1,3-oxazol-2(3H)-one and its applications in asymmetric carbon-carbon bond formation are described.

An easy synthetic approach to fused polycyclic aromatic hydrocarbons that is based on the ceric ammonium nitrate-promoted oxidative addition of 3-aryl-1-((trimethylsilyl)oxy)cyclohexenes to the ethyl vinyl ether in methanol is presented. The wide applicability of the method is demonstrated by its use in the synthesis of the unknown hydroxynaphthothiophenes and the preparation of 1-chrysenol in 65% yield from 3-(beta-naphthyl)-1-((trimethylsilyl)oxy)cyclohexene.

A novel synthetic route to substituted 1(2H)-phenanthrenones was developed based on the ceric ammonium nitrate-promoted oxidative addition of 3-aryl-1-{(trimethylsilyl)oxy}-cyclohexanes to ethyl vinyl ether. The findings showed that the cyclization process had a high degree of stereoselectivity with the introduction of 3-Y-substituted aryl derivatives. The results also revealed that 6-substituted 3,4-dihydrophenenthren-1-ones were the critical regioisomers under all conditions considered.

A novel method for the synthesis of (R)-4-hydroxy-, -4-fluoro, -4-bromo and -4-iodo[2.2]paracyclophanes was developed based on the utilization of (R)-(-)-4-amino[2.2]paracyclophane. The synthetic strategy was characterized by the generation of (R)-(-)-4-amino[2.2]cyclophane by the metalation of (R)-(-)-4-bromo[2.2]paracyclophane with n-butyllithium and successive animation of the resulting 4-lithio derivative. The target compound was also obtained by the alkaline hydrolysis of (R)-4-acetoxy[2.2]paracyclophane which was derived from the intermediate product.

Highly functionalized and regio- and stereoselective 2,3-disubstituted cycloalkenes were produced by cerium(IV) ammonium nitrate-promoted (CAN) addition. CAN was utilized as a catalysis for the addition of 1-ethoxy-1-[(trimethylsilyl)-oxy]cyclopropane to 2-cycloalkenones with vinyl ether and allyltrimethylsilane. Hydrogen abstraction of the solvent by the main product, ethyl propopionate, produces a beta-(ethoxycarbonyl)alkyl radical. Alpha-carbonylalkyl radical was produced from the addition of beta-(ethoxycarbonyl)alkyl to the beta-carbon of the cycloalkenone.

Research describes the utility of fluorine in the synthesis of fluorinated drugs. The synthetic procedure is based on the ceric ammonium nitrate-promoted oxidative addition of O-silyl and O-alkyl enethers to ethyl vinyl ether.

The vibrational absorption spectra and vibrational circular dichroism (VCD) spectra of both enantiomers of 4-X-[2.2]paracyclophanes (X = COOC[D.sub.3], Cl, I) are recorded. The analysis of the near-infrared (NIR) region for X = COOC[D.sub.3] has disclosed important features of the aromatic CH stretching overtones that are important since the aromatic CH stretching fundamentals are almost silent.

Atropisomeric (R,R)-2,2'-bi([2]paracyclo[2](5,8)quinolinophane) [(R,R)-1] and (R,R)-1,1'bi([2]paracyclo[2](5,8)isoquinolinophane) [(R,R)-2] are prepared in moderate overall yield by a four step sequence starting from (R)-(-)4-amino[2.2]paracyclophane and (R)-(-)-4-carboxy[2.2]paracyclophane respectively. The main spectral data can be interpreted in terms of an almost planar 2,2'-bisquinoline chromophore inserted in a paracyclophane structure in the case of (R,R)-1, while in the case of (R,R)-2 the main role is played by a distorted 1,1'-bisiquinoline chromophore.

Regioselectivity nucleus and/or side-chain fluorinated 2-(phenanthr-1-yl)- and 2-(phenanthr-2-yl)-propionic acids were prepared using phenanthren-1(2H)-ones as key intermediates. Fluorinated drugs include a vast range of pharmaceutical applications from anesthetics to chemotherapeutic drugs from corticoids to narcoleptics and even cardiovascular drugs.

Research has been conducted on cyclohex-3-ene-1,1-bis(phosphonates). The authors demonstrate that this compound can be obtained during the reactions of tetraethyl vinylidenebis(phosphonate) with substituted 1,3-dienes without solvent.

Research has been conducted on beta-elimination reactions. The mechanism of the base-induced beta-elimination reactions in pyridine ring activated systems with fluorine as a leaving group is described.

In recent years, a large number of in silico and in vitro assays have been developed for safety assessment in early drug discovery. These methods are usually validated using datasets of known drugs with large chemical diversity, while application to homologous series has been rarely explored. Here we report a case study about phospholipidosis (PLD) risk evaluation for a dataset of nine compounds, designed and synthesized to modulate the physico-chemical properties typical of cationic amphiphilic compounds (CADs), representing the main class of PLD inducers. Our aim was to investigate the effect of structure modification on PLD induction according to a number of standard in silico and in vitro methods. As a result, we found that different in silico methods lead to conflicting results when applied to our series of weak PLD inducers, thus the apparently easy-to-use definition of CADs requires special attention. Moreover, when weak inducers are tested in vitro, the revealed PLD effect may vary based on the purity grade of the tested compound and the features of the selected assay. Finally, we have shown that slight modifications on a chemical scaffold can have an impact on the PLD effect. This study also exemplifies that current in silico methods possibly overestimate the PLD induction effect of cationic amphiphilic compounds compared to the in vitro, with the risk of discarding promising compounds based on incorrect safety liabilities. [ABSTRACT FROM AUTHOR]