The enantioselective total syntheses of eight cladiellin natural products

The cladiellins (also known as eunicellins) are oxygen-bridged 2,11–cyclised cembranoids, isolated from gorgonian octocorals and soft corals. They present an unusual oxatricyclic ring system composed of a hydroisobenzofuran and an oxonene unit. The natural role of these cembranoids is proposed to involve predatation deterrence, and biologically they have been shown to exhibit in vitro cytotoxicity against various cancer cell lines, anti inflammatory properties antimicrobial activities. The Clark group has been interested in the synthesis of cladiellins for some time, and in 2007 Clark and co-workers reported the total synthesis of vigulariol. This thesis describes the investigation of the synthesis of both E- and Z-cladiellins using our general strategy. The key transformations in the synthetic route are ring formation reactions. Firstly, a SmI2-mediated reductive cyclisation forms the tetrahydropyran ring, then a tandem oxonium ylide formation [2,3]-sigmatropic rearrangement constructs the oxabicyclo[6.2.1]undecenone bicyclic core. Finally, a Diels-Alder cycloaddition reaction forms the third ring of the tricyclic core of the cladiellins. Particular interest was given to the tandem oxonium ylide formation [2,3]-sigmatropic rearrangement reaction. This transformation was studied in order to develop conditions allowing the selective formation of the E-oxonene ring needed for the synthesis of the E-cladiellin tricyclic core. Herein, is presented work towards the synthesis of ophirin B, a cladiellin bearing a Z-oxonene alkene, as well as the enantioselective total synthesis of eight cladiellins obtained from an E-cladiellin tricyclic core: (−)-cladiella-6,11-dien-3-ol, (−)-cladiell-11-ene-3,6,7-triol, (−)-3-acetoxycladiella-6,11-diene, 3-acetoxy-cladiellin-11-ene-6,7-diol, (−)-sclerophytin A, (−)-sclerophytin B, (+)-deacetylpolyanthellin A and (+)-polyanthellin A in 20 to 24 steps from our allylic alcohol precursor

A Bayesian approach to quantifying the effects of mass poultry vaccination upon the spatial and temporal dynamics of H5N1 in Northern Vietnam.

Published versio

L’acceptabilité sociale des projets d’aménagement du territoire et d’urbanisme: Balises et recommandations

La présente note de recherche fait état des principaux résultats de deux ans de recherche sur l'acceptabilité sociale des projets d'urbanisme et d’aménagement du territoire. La recherche est principalement centrée sur deux types de projets chargés de contribuer à la transition écologique, à savoir les projets de densification des centralités d’une part, et d’infrastructures énergétiques d’autre part (projets d’infrastructures linéaires électriques et projets éoliens).Il s’agit de revenir sur les principaux facteurs d’acceptabilité sociale de ces grands projets et sur les principales recommandations émises en vue d’en améliorer les processus d’acceptabilité sociale.info:eu-repo/semantics/publishe

Audio-Visual Perception of Gender by Infants Emerges Earlier for Adult-Directed Speech

International audienceEarly multisensory perceptual experiences shape the abilities of infants to perform socially-relevant visual categorization, such as the extraction of gender, age, and emotion from faces. Here, we investigated whether multisensory perception of gender is influenced by infant-directed (IDS) or adult-directed (ADS) speech. Six-, 9-, and 12-month-old infants saw side-by-side silent video-clips of talking faces (a male and a female) and heard either a soundtrack of a female or a male voice telling a story in IDS or ADS. Infants participated in only one condition, either IDS or ADS. Consistent with earlier work, infants displayed advantages in matching female relative to male faces and voices. Moreover, the new finding that emerged in the current study was that extraction of gender from face and voice was stronger at 6 months with ADS than with IDS, whereas at 9 and 12 months, matching did not differ for IDS versus ADS. The results indicate that the ability to perceive gender in audiovisual speech is influenced by speech manner. Our data suggest that infants may extract multisen-sory gender information developmentally earlier when looking at adults engaged in conversation with other adults (i.e., ADS) than when adults are directly talking to them (i.e., IDS). Overall, our findings imply that the circumstances of social interaction may shape early mul-tisensory abilities to perceive gender

Mean proportion of total looking time to the face that matched the heard voice in each condition (IDS, ADS) and for each age group (6-, 9-, 12-month-olds).

<p><i>Note</i>: *<i>p</i> < .05; Error bars represent <i>SD</i>s.</p

Schematic representation of the procedure.

<p>Infants saw two side-by-side silent video-clips presenting a male and a female face reciting a nursery rhyme. A soundtrack with a female or a male voice telling a story in IDS or ADS was played at the same time. The video-clips were repeated twice throughout the four trials, with left-right reversal for the positioning of the faces. (The individuals in this figure have given written informed consent (as outlined in PLOS consent form) to publish their pictures.)</p