Oxidation of Alcohols in Continuous Flow with a Solid Phase Hypervalent Iodine Catalyst

One of the most useful transformations in the synthetic chemist arsenal is the oxidation of alcohols to their corresponding carbonyl congeners. Despite its seemingly straightforward nature, this transformative reaction predominantly relies on the use of metals or hazardous reagents, making these processes highly unsustainable. To address this challenge, we have developed a sustainable metal-free method for the oxidation of alcohols in continuous flow. Using a solid phase hypervalent iodine catalyst and nBu4HSO5 as a phase transfer catalyst and co-oxidant, primary and secondary alcohols were selectively oxidized to the corresponding carbonyl motifs. This operationally simple continuous-flow set-up is highly robust (15 cycles run without significant catalyst leaching or loss of reaction efficiency), uses green solvents, such as acetonitrile or acetic acid, and is readily scalable.

Correlation between asymmetric dimethylarginine maternal plasma levels and preeclampsia

OBJECTIVE

To aim of our study is to support the correlation between blood pressure and asymmetric dimethyl argine (ADMA) concentrations as a possible marker for early diagnosis of the preeclampsia syndrome.

STUDY DESIGN

We attempted to calculate in 38 pregnant women with preeclampsia (group A) plasma levels of the main inhibitor to nitric oxide synthase (NOS), which is ADMA, and to compare our findings with the levels of ADMA in 36 non preeclamptic pregnant women (group C) and also with the levels in 29 pregnant women who had a history of preeclampsia in previous pregnancies (group B). Maternal venous EDTA plasma samples of 5 ml were collected and analyzed to measure the ADMA concentrations in each subject. Statistical analysis was performed using the Graph Pad Instat Mann-Whitney test, unpaired, non parametric test, two-tail p values.

RESULTS

There was no statistical difference between the three groups regarding maternal and gestational age (24-32 weeks). There was a significant statistical difference between the three groups regarding ADMA levels. The two-tailed p value between group A and group C (normal group) was < 0.001, between group A and group B < 0.002 and between group B and group C < 0.002.

CONCLUSION

In conclusion we have observed that ADMA probably fulfills many of the criteria to be characterized as a preeclamptic factor and an accurate cut-off point matched to each week of pregnancy should be determined.