Ligand-centred reactivity of bis(picolyl)amine iridium: sequential deprotonation, oxidation and oxygenation of a "non-innocent" ligand.

Treatment of [Ir(bpa)(cod)](+) complex [1](+) with a strong base (e.g., tBuO(-)) led to unexpected double deprotonation to form the anionic [Ir(bpa-2H)(cod)](-) species [3](-), via the mono-deprotonated neutral amido complex [Ir(bpa-H)(cod)] as an isolable intermediate. A certain degree of aromaticity of the obtained metal-chelate ring may explain the favourable double deprotonation. The rhodium analogue [4](-) was prepared in situ. The new species [M(bpa-2H)(cod)](-) (M = Rh, Ir) are best described as two-electron reduced analogues of the cationic imine complexes [M(I)(cod)(Py-CH(2)-N=CH-Py)](+). One-electron oxidation of [3](-) and [4](-) produced the ligand radical complexes [3](*) and [4](*). Oxygenation of [3](-) with O(2) gave the neutral carboxamido complex [Ir(cod)(py-CH(2)-N-CO-py)] via the ligand radical complex [3](*) as a detectable intermediate.

Deprotonation induced ligand-to-metal electron transfer: synthesis of a mixed-valence Rh(-I,I) dinuclear compound and its reaction with dioxygen.

Treatment of bis(2-picolyl)amine (bpa) with [{Rh(nbd)(mu-OMe)}2] leads to the unexpected and unique redox asymmetric dinuclear Rh-I,Rh+I complex [{Rh(nbd)}2(bpa-2H)] (2) with a pi-coordinating imine bound to a tetrahedral low valent rhodate(-I). Mono-oxygenation of the deprotonated bpa ligand in 2 by O2 leads to the mononuclear carboxamido complex [Rh(nbd)(bpam-H)] (3) (bpam = N-(2-picolyl)picolinamide). The second O atom of O2 ends up as a hydroxo fragment in [{Rh(nbd)(mu-OH)}2].

Relationship between Helicobacter pylori seropositivity and hyperemesis gravidarum with the use of questionnaire.

AIM: The aim of the present study was to investigate the relationship between Helicobacter pylori (HP) infection and Hyperemesis gravidarum (HG) by using a questionnaire. METHODS: Twenty-five pregnant women with HG and 85 asymptomatic pregnant women (aged 14-40) of matching gestational age were enrolled between October 2004 and January 2006. Anti-HP immunoglobin G (IgG) serum antibody was tested to establish seropositivity. In our study we used a multi variable questionnaire (name, age, gravida, number of vomits daily etc.). The results were analyzed using chi squared and Mann-Whitney U- test. RESULTS: The prevalence of HP infection was 56% (14 of 25) among patients with Hyperemesis gravidarum and 48.2% (41 of 85) among control subjects (P>0.05, chi squared test). In the same study the HP seropositivity is not related to age of the woman (50%, 55 of 110 were HP positive, P>0.05 chi squared test) but there was a significantly association between number of deliveries and HP seropositivity (primigravida [+] 34.2% versus 65.8%, multigravida [+] 6.1% versus 38.9%, P<0.05 chi squared test). The history for gastrointestinal problems of the tested women and their husbands is not related to HP seropositivity(38.1% positive for HP and with gastrointestinal disorders she/he or both versus 61.8% positive and without problems both, P>0.05, Mann-Whitney U- test). Finally there was no relativity between the number of vomits daily and the HP seropositivity (48.2% with HP [+] and 0-3 vomits daily versus 56% with HP [+] and 4-8 vomits daily, P>0.05 chi squared). CONCLUSIONS: Our findings do not support any direct correlation between HP seropositivity and Hyperemesis gravidarum, number of vomits daily, age of woman, history for gastrointestinal problems but only with the number of deliveries.