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Thiele condensation of the [2.2]paracyclophane derivatives 8, 12, 22, and 23 with cyclopentadiene (9) led to the monofulvenes 10, 11, and 13 and the bis(fulvenes) 24 and 25. Likewise, condensations of 8 with 1,2,3,4-tetrachlorocyclopentadiene (14) and 1,2,3,4-tetraphenylcyclopentadiene (16) provided the 4-fulvenyl[2.2]paracyclophanes 15 and 17. For comparison purposes, 8 was also condensed with lithium fluorenide (18) and lithium indenide (20) to give the benzo-annelated derivatives 19 and 21, respectively. Reactions of the dialdehydes 22 and 23 led to the bis(indenes) 26 and 27. 4-(6-Fulvenyl)[2.2]paracyclophane exists as two conformational isomers, 10 (major product) and 11 (minor product). By temperature-dependent NMR spectroscopy, the rotational barrier associated with 11 ? 10 interconversion has been determined as ca. 26 kcal mol-1 at 70 �C. The structures of 19 and 27 have been established by single-crystal X-ray crystallography.

Des examens de sol ont été effectués en Irlande et en Grande-Bretagne pour rechercher les nématodes du genre #Heterorhabditis$. Des échantillons des sols prélevés sur des sites sablonneux furent pourvus de larves de #Galleria mellonella$ comme appâts. Des #Heterorhabditis$ furent collectés sur 18 sites sur 169 en Irlande, 2 sur 51 dans le nord de l'Ecosse et 9 sur 20 dans le sud du Pays de Galle. Tous les sites positifs sont situés sur le littoral ; aucun #Heterorhabditis$ n'a été détecté dans les échantillons prélevés dans 40 sites situés à l'intérieur des terres. La totalité des 76 isolats recueillis au cours de ces analyses ont été identifiés comme appartenant au groupe irlandais d'#Heterorhabditis$, à l'aide de méthodes de concentration isoélectrique, de restriction de l'ADN et d'hybridation. Aucun #Heterohabditis$ appartenant au groupe de l'Europe du nord-ouest n'a été recueilli. Cependant, un isolat recueilli par d'autres chercheurs et provenant du sud de l'Angleterre a été identifié comme appartenant à ce groupe. Les membres du groupe irlandais ne se croisent généralement pas avec les membres du groupe de l'Europe du nord-ouest, bien que des juvéniles infestants fertiles aient été produits dans un nombre limité (3/15) de croisements entre ces groupes. (Résumé d'auteur)

Entomopathogenic nematodes of the genus Heterorhabditis are morphologically conservative, consequently the majority of isolates remain unassigned at the species level. When a Heterorhabditis infective juvenile infects an insect host, it develops into a protandrous hermaphrodite female. These first-generation females give rise to a second generation which contains both males and females. Because of this complex life-cycle and also because of uncertainty as to whether second-generation females are amphimictic, cross-breeding studies to facilitate species determination have not been carried out previously. We demonstrate here that second-generation Heterorhabditis females are amphimictic. Because of this finding, we have been able to develop a successful cross-breeding technique for the purposes of species determination in Heterorhabditis. Interstrain crosses using second-generation males and females from the appropriate strains have been successfully set up in Xenorhabdus luminescens-treated G. mellonella cadavers and also on agar plates. Using the techniques described here we confirm that H . bacteriophora (Brecon strain), H . megidis and H . zealandica are distinct biological species, we note that the H. bacteriophora group contains at least 2 species and we provide evidence for the existence of a new Irish species of Heterorhabditis.

4,5,12,13-Tetraformyl[2.2]paracyclophane (1f) has been prepared for the first time by the cycloaddition of 4,4-diethoxy-2-butynal (3) to 1,2,4,5-hexatetraene (2) under various conditions and hydrolysis of the initially produced bis-acetals 5a and 5b. An X-ray crystal structural analysis of 5a is reported.

Foreign substances can have a dramatic and unpredictable adverse effect on human health. In the development of new therapeutic agents, it is essential that the potential adverse effects of all candidates be identified as early as possible. The field of predictive toxicology strives to profile the potential for adverse effects of novel chemical substances before they occur, both with traditional in vivo experimental approaches and increasingly through the development of in vitro and computational methods which can supplement and reduce the need for animal testing. To be maximally effective, the field needs access to the largest possible knowledge base of previous toxicology findings, and such results need to be made available in such a fashion so as to be interoperable, comparable, and compatible with standard toolkits. This necessitates the development of open, public, computable, and standardized toxicology vocabularies and ontologies so as to support the applications required by in silico, in vitro, and in vivo toxicology methods and related analysis and reporting activities. Such ontology development will support data management, model building, integrated analysis, validation and reporting, including regulatory reporting and alternative testing submission requirements as required by guidelines such as the REACH legislation, leading to new scientific advances in a mechanistically-based predictive toxicology. Numerous existing ontology and standards initiatives can contribute to the creation of a toxicology ontology supporting the needs of predictive toxicology and risk assessment. Additionally, new ontologies are needed to satisfy practical use cases and scenarios where gaps currently exist. Developing and integrating these resources will require a well-coordinated and sustained effort across numerous stakeholders engaged in a public-private partnership. In this communication, we set out a roadmap for the development of an integrated toxicology ontology, harnessing existing resources where applicable. We describe the stakeholders' requirements analysis from the academic and industry perspectives, timelines, and expected benefits of this initiative, with a view to engagement with the wider community.

4-(2,3,4,5-Tetraphenyl)phenyl[2.2]paracyclophane (3) has been prepared by cycloaddition of tetracyclone (2) to 4-ethynyl[2.2]paracyclophane (1). On treatment with FeCl3 or AlCl3 or NOBF4 in nitromethane, 3 undergoes C-C bond cleavage by an electron transfer process to provide the double benzyl radical cation 10. The phenyl groups of the aryl substituent are ideally oriented for intramolecular trapping and, in the presence of the Lewis acids, ring closure to the new phane system 5 takes place in good yield (65%). In the presence of NOBF4, the half-cyclized aldehyde 6 (66%) is produced. For comparison, [2.2]paracyclophane (7) was also treated with the latter one-electron oxidant, providing bibenzyl-4,4'-dicarbaldehyde (8, 30%) and its monooxime 9 (35%). The structures of the new phane systems 3 and 5 have been determined by X-ray structural analysis, and the mechanisms leading to these products are discussed.