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Mitochondrial (mt) nucleoids were isolated with a high degree of purity from the yeast Pichia jadinii, in which the mitochondrial DNA (mtDNA) is linear. Field-inversion gel electrophoresis (FIGE) revealed that significant amounts of mtDNA could be isolated intact, as linear molecules of 41 kbp, from the isolated mt-nucleoids. Fifteen different proteins were detected in the mt-nucleoid fraction and, eight of these proteins bound to DNA. The patterns of mt-nucleoid proteins and of the DNA-binding proteins after gel electrophoresis in the presence of SDS were somewhat different from those of such proteins from Saccharomyces cerevisiae. The corresponding proteins isolated from the mt-nucleoids of four other species of yeast in the genera Pichia and Williopsis also differed from one another in terms of electrophoretic mobility in the presence of SDS. In immunoblotting experiments, antibodies that had been raised against the 67-kDa protein of mt-nucleoids from S.cerevisiae and the YMN-1 monoclonal antibody that is specific for a 48-kDa protein in the mt-nucleoids from S. cerevisiae did not recognize any proteins in the mt-nucleoids from Pichia jadinii and four other species of yeast. The results suggest the considerable diversity of the proteins in the mt-nucleoids of yeasts.

Refluxing tris(β-diketonato) complexes of rare earth elements (Ln) with dilithium phthalocyaninate (Li2Pc) in dried organic solvents resulted in mixed-ligand complexes of diverse composition depending on the β-diketones and solvents used. With dipivaloylmethane (dpmH) used as the β-diketone, two types of novel complexes, Ln2Pc(dpm)4 and [LnPc · (dpm)2]2, were obtained. By X-ray analysis the samarium complex of the former type was shown to have an axially symmetric Pc bridge binding two Sm atoms. The complexes of the latter type have an unpaired electron on the Pc ligand, as proved by the paramagnetism of the yttrium compound, and seem to be formed by atmospheric oxidation during the reflux. Other types of complexes obtained are: LnPc(dbm)(solv)2, LnPcH(dbm)2(solv)2 and LnPcH(acac)2 where dbmH = dibenzoylmethane and acacH = acetylacetone. The magnetic susceptibilities of the binuclear series Ln2Pc(dpm)4 conformed to the van Vleck-Frank formula down to 77 K, except that complexes with Ln ≡ Er, Tm and Yb gave somewhat large absolute values of the Curie-Weiss constants (θ = 23, 20 and −50 K where χ = C (T − θ) ). A comparative study disclosed that Yb(dpm)3 and even YbCl3 · 6H2O gave θ also in the neighborhood of −50 K, although Tm(dpm)3 and Er(dpm)3 showed θ values close to 0.

The reaction of tris(1,3-diphenyl-1,3-propanedionato) complexes of heavier rare-earth elements, M3+(dbm)3 and lithium phthalocyaninato(2−), Li2(pc) gave two types of new stable phthalocyanine complexes, [M3+(pc) (dbm) (dbmH)] and [M3+(pc) (dbm)] depending on the solvents used for the preparation. The structure of both types of complexes are tentatively proposed.

μ-Oxo-bis[(hydroxo)(octaethylporphyrinato)ruthenium(IV)] was prepared by the oxidation of (carbonyl)(octaethylporphyrinato)ruthenium(II) with t-butyl hydroperoxide in good yield. Facile replacement of the hydroxyl group with various anions afforded μ-oxo dimer complexes formulated as [{RuIV(oep)X}2O] (X=Cl, Br, and OCOCH3). The same type of osmium complexes, [{OsIV(oep)(OCH3)}O], {[OsIV(oep)(OCH3)}O{OsIV(oep)(OH)}], and [{OsIV(oep)(OH)}2O] were obtained from the air oxidation product of (carbonyl)(methanol)(octaethylporphyrinato)osmium(II) in the presence of 2,3-dimethylindole. These complexes are diamagnetic. The 1H NMR data are in conformity with the linear oxo-bridged dimer structure which was proved by X-ray crystallography with [{RuIV(oep)(OH)}2O]. The redox potentials were measured by the cyclic voltammetry. These complexes showed three distinct quasi-reversible redox couples assignable to metalII/ metalIII, metalIII/metalIV, and porphyrin ligand oxidation, respectively. Significantly lower redox va...

The reaction of tris(2,2,6,6-tetramethyl-3,5-heptanedionato) complexes of rare-earth elements, M3+(dpm)3 (M = Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y) with lithium phthalocyanine Li2(Pc2−) in tetrahydrofuran gave new stable phthalocyanine radical complexes [M3+(Pc−·)(dpm)2].

The reaction of dilithium phthalocyanine with tris(2,2,6,6-tetramethylheptane-3,5-dionato) Lnlll (Ln = Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Y) affords a series of (p-phthalocyaninato) (diketonato),Ln, complexes; the X-ray crystal structure of the samarium compound shows that the phthalocyanine ligand bridges two samarium atoms each co-ordinated by two /3-diketonato ligands, and important molecular parameters include Sm-Oav 2.284(17), Sm-Nav 2.656(16), and Sm-Smav 3.627(3) A.

The oxidation of the dilithium salt of phthalocyanine Li2(pc2–) with iodine gave the free radical of phthalocyanine, H(pc–), while the electrochemical oxidation of the same starting material gave the lithium salt, Li(pc–); these stable free radicals were characterized by spectroscopic and magnetic measurements.