An unstable intermediate has been detected and isolated in the reaction of ozone with C60 in solution. On the basis of its UV−vis absorption spectrum, the measured release of O2 in its decay to the epoxide C60O, and the first-order kinetics of this reaction, the intermediate has been identified as C60O3, a primary ozonide. This [6,6]-closed adduct of ozone with C60 thermally dissociates to C60O plus O2 in toluene solution, octane solution, and the solid phase with rate constants (at 23 °C) of 4.6 × 10-2, 1.3 × 10-3, and 3.0 × 10-3 min-1, respectively. The activation energy for dissociation in toluene solution is approximately 89 kJ mol-1. Semiempirical quantum calculations indicate that the formation and subsequent dissociation of C60O3 are both exothermic processes. These findings constitute the first observation of a fullerene ozonide.

et al. / A novel water-soluble fluorescent probe Mass spectrometry. (5-I3C)-Retinal: m/z 285 (M + ); I3C incorporation calcd. from the mass spectra: 85%; exact mass calcd. for '3C,,'3CH,,0: 258.2174; found: 285.2164. ( 18-'3C)-Retinal: m/z 285 ( M + ) ; I3C incorporation calcd. from the mass spectra: 92.4%.from the Netherlands Organization for the Advancement of Pure Research (ZWO). The authors wich to hank Drs. C. Erkelens and Mr. F. Lefeber for recording the NMR spectra and Mr. J . J. van Houte for recording the mass spectra. The manuscript was reviewed by Miss S. Amadio.Abstract. The reaction of the 3,3',5,5'-tetramethyI-2,2'-pyrromethen-1,l '-BF, complex with chlorosulfonic acid and its subsequent neutralisation with sodium bicarbonate yields the titled compound 1, which, in addition to appropriate thermal and photochemical stability, possesses excellent fluorescent properties. As a preliminary assay of its potential usefulness as a fluorescent probe in medical and biological research, the chemical was administered intravenously to rats and possible signs of toxicity were recorded. The rats showed no apparent detrimental effects and excreted the compound in the urine within three hours. In tests in which Salmonella and E. coli strains were used as indicators of genotoxicity, no mutagenic effects were observed.

There is a general fascination with regard to the origin of life on Earth. There is an intriguing possibility that prebiotic precursors of life occurred in the interstellar space and were then transported to the early Earth by comets, asteroids and meteorites. It is probable that some part of the prebiotic molecules may have been generated by gas-phase ion/molecule reactions. Here we show experimentally that gaseous ion/molecule reactions of the amino acids, Glu and Met, may promote the synthesis of protonated dipeptides such as (GluGlu)H and (Glu-Met)H and their chemical growth to larger protonated peptides.

Gel-filtration and thin layer chromatography of low molecular weight carbohydrates from culture filtrates of Agrobacterium radiobacter, Isolate II, have shown, that next to the neutral beta-1,2-glucan fraction a major acidic fraction was present which was found to be glycerophosphorylated cyclic beta-1,2-glucans. Re-examination of cyclic beta-1,2-glucan preparations which had been obtained by extraction of Rhizobium cells with hot phenol-water also showed these acidic modified beta-1,2-glucans to be present. Cyclic beta-1,2-glucans from R. leguminosarum (9 strains) and of R. phaseoli (1 strain) had ring size distribution with degrees of polymerisation (DPs) of 19 and 20 as major ring sizes of which a minor part was glycerophosphorylated; beta-1,2-glucans of R. trifolii (3 strains) had ring sizes with DPs measuring 19-22 as prominent components which were largely unsubstituted, and R. meliloti (7 strains) had beta-1,2-glucans with ring size distributions extending to still higher DPs of 19-25 of which the major part appeared to be glycerophosphorylated.

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