The preparation of the first photochromic, organometallic derivative of the diarylethene class, the CpRu-complexed benzodimethyldihydropyrene 3, in which the organometallic is directly attached to the photochromic core, is described. The negative dark purple photochrome 3 readily bleaches to form the almost colorless cyclophanediene 3' on irradiation with visible light. The latter switches back to 3 either photochromically with UV light, electrochromically on reduction, or thermochromically on heating. Essentially quantitative conversion between the two states is possible. The open complex 3' thermally closes 2.6 times faster than the uncomplexed parent 2', but the closed form 3 opens with visible light at about 30% of the rate of uncomplexed 2. Both open forms, complexed 3' and uncomplexed 2' close equally fast with UV light.

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The tricarbonylchromium complex of 2,7-di-tert-butyl-trans-12c,12d-dimethylbenzo[e]dihydropyrene is prepared in 65% yield from the parent annulene. Analysis of the (1)H NMR spectrum leads to coupling constant data and Günther's "Q" value data which unequivocally indicate that the tricarbonylchromiumbenzene moiety behaves like an aromatic system of greater bond fixing ability, aromaticity, than benzene itself; this analysis is supported by X-ray structural data and by the rotational position of the tricarbonyl podal. Analysis of chemical shift data indicates that the tricarbonylchromium benzene moiety has about 25% enhanced "aromaticity" over that of benzene.

Mittel gegen Superbugs? Zwei neue synthetische dikationische Peptoide (siehe Beispiel; rot O, blau N, grün Cl) zeigen vielversprechende antibakterielle Aktivität in vitro gegen etliche Gram‐positive Pathogene – einschließlich Vancomycin‐, Methicillin‐ und Linezolid‐resistenter Organismen – bei nur langsamer Resistenzentwicklung. Ihre Wirksamkeit bleibt darüber hinaus auch in vivo erhalten.

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