Synthesis and formation mechanism of VO2(A) nanoplates with intrinsic peroxidase-like activity

1,2,3-Triazole-4-carbaldehydes are useful synthetic intermediates which may play an important role in the discovery of novel applications of the 1,2,3-triazole moiety. In this work, a one-step multigram scale synthesis of 4-formyl-1-(4-nitrophenyl)-1H-1,2,3-triazole (FNPT) as a preferred reagent for the synthesis of 1-alkyl-4-formyltriazoles is described, making use of the commercially available 3-dimethylaminoacrolein and 4-nitrophenyl azide. Next, the earlier reported reaction of FNPT with alkylamines is further explored, and for hexylamine, the one-pot sequential cycloaddition and Cornforth rearrangement is demonstrated. In addition, a useful protocol for the in situ diazotization of 4-nitroaniline is provided. This facilitated the complete hydrolysis of rearranged 4-iminomethyl-1,2,3-triazoles and allowed for the recycling of 4-nitrophenyl azide.

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INDIREKTE PAPIERCHROMATOGRAPHISCHE METHODE ZUR BESTIMMUNG DER HARNOESTROGENE

Acta Endocrinologica ◽

10.1530/acta.0.0380545 ◽

1961 ◽

Vol 38 (4) ◽

pp. 545-562 ◽

Cited By ~ 2

Author(s):

L. Kecskés ◽

F. Mutschler ◽

I. Glós ◽

E. Thán ◽

I. Farkas ◽

...

Keyword(s):

Pregnant Women ◽

Granulosa Cell ◽

Iron Content ◽

List Type ◽

Granulosa Cell Tumour ◽

Hydrolysis Of ◽

Phenol Fraction ◽

Qualitative Determination

ABSTRACT 1. An indirect paperchromatographic method is described for separating urinary oestrogens; this consists of the following steps: acidic hydrolysis, extraction with ether, dissociation of phenol-fractions with partition between the solvents. Previous purification of phenol fraction with the aid of paperchromatography. The elution of oestrogen containing fractions is followed by acetylation. Oestrogen acetate is isolated by re-chromatography. The chromatogram was developed after hydrolysis of the oestrogens 'in situ' on the paper. The quantity of oestrogens was determined indirectly, by means of an iron-reaction, after the elution of the iron content of the oestrogen spot, which was developed by the Jellinek-reaction. 2. The method described above is satisfactory for determining urinary oestrogen, 17β-oestradiol and oestriol, but could include 16-epioestriol and other oestrogenic metabolites. 3. The sensitivity of the method is 1.3–1.6 μg/24 hours. 4. The quantitative and qualitative determination of urinary oestrogens with the above mentioned method was performed in 50 pregnant and 9 non pregnant women, and also in 2 patients with granulosa cell tumour.

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In Situ Microscopy for In-line Monitoring of the Enzymatic Hydrolysis of Cellulose

Analytical Chemistry ◽

10.1021/ac4008495 ◽

2013 ◽

Vol 85 (17) ◽

pp. 8121-8126 ◽

Cited By ~ 11

Author(s):

Britta Opitz ◽

Andreas Prediger ◽

Christian Lüder ◽

Marrit Eckstein ◽

Lutz Hilterhaus ◽

...

Keyword(s):

Enzymatic Hydrolysis ◽

Enzymatic Hydrolysis Of Cellulose ◽

Hydrolysis Of Cellulose ◽

Hydrolysis Of

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In situ total scattering experiments of nucleation and crystallisation of tantalum-based oxides: from highly dilute solutions via cluster formation to nanoparticles

Nanoscale ◽

10.1039/d0nr07871a ◽

2021 ◽

Vol 13 (1) ◽

pp. 150-162

Author(s):

Ezgi Onur Şahin ◽

Harun Tüysüz ◽

Candace K. Chan ◽

Gun-hee Moon ◽

Yitao Dai ◽

...

Keyword(s):

Formation Mechanism ◽

Cluster Formation ◽

Dilute Solutions ◽

Total Scattering ◽

Alkoxide Precursors

The formation mechanism of amorphous tantalum oxides was studied by total scattering experiments starting from alkoxide precursors. Hydrolysed TaxOyHz clusters form in highly dilute solutions which were transformed into L-Ta2O5 by calcination.

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Permeability of muscle capillaries to small heme-peptides. Evidence for the existence of patent transendothelial channels.

The Journal of Cell Biology ◽

10.1083/jcb.64.3.586 ◽

1975 ◽

Vol 64 (3) ◽

pp. 586-607 ◽

Cited By ~ 380

Author(s):

N Simionescu ◽

M Siminoescu ◽

G E Palade

Keyword(s):

Plasma Proteins ◽

Intercellular Junctions ◽

Rat Diaphragm ◽

Enzymic Hydrolysis ◽

Graphic Analysis ◽

Heme Peptides ◽

Future Work ◽

Hydrolysis Of ◽

Muscle Capillaries

Two heme-peptides (HP) of about 20-A diameter (heme-undecapeptide [H11P], mol wt approximately 1900 and heme-octapeptide [H8P], mol wt approximately 1550), obtained by enzymic hydrolysis of cytochrome c, were sued as probe molecules in muscle capillaries (rat diaphragm). They were localized in situ by a perixidase reaction, enhanced by the addition of imidazole to the incubation medium. Chromatography of plasma samples showed that HPs circulate predominantly as monomers for the duration of the experiments and are bound by aldehyde fixatives to plasma proteins to the extent of approximately 50% (H8P) to approximately 95% (H11P). Both tracers cross the endothelium primarily via plasmalemmal vesicles which become progressively labeled (by reaction product) from the blood front to the tissue front of the endothelium, in three successive resolvable phases. By the end of each phase the extent of labeling reaches greater than 90% of the corresponding vesicle population. Labeled vesicles appear as either isolated units or chains which form patent channels across the endothelium. The patency of these channels was checked by specimen tilting and graphic analysis of their images. No evidence was found for early or preferential marking of the intercellular junctions and spaces by reaction product. It is concluded that the channels are the most likely candidate for structural equivalents of the small pores of the capillary wall since they are continuous, water-filled passages, and are provided with one or more strictures of less than 100 A. Their frequency remains to be established by future work.

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