2434-53-9Relevant articles and documents
A uracil nitroso amine based colorimetric sensor for the detection of Cu2+ ions from aqueous environment and its practical applications
Patil, Samadhan R.,Nandre, Jitendra P.,Patil, Prashant A.,Sahoo, Suban K.,Devi, Manisha,Pradeep, Chullikkattil P.,Fabiao, Yu,Chen, Lingxin,Redshaw, Carl,Patil, Umesh D.
, p. 21464 - 21470 (2015)
A simple uracil nitroso amine based colorimetric chemosensor (UNA-1) has been synthesized and screened for its cation recognition ability. Sensor UNA-1 exhibited a high sensitivity and selectivity towards Cu2+ ions in aqueous medium in the presence of a wide range of other competing cations (Ag+, Al3+, Ba2+, Ca2+, Cd2+, Co2+, Cr3+, Cs+, Fe2+, Fe3+, Li+, Mg2+, Mn2+, Na+, Ni2+, Pb2+, Zn2+, Hg2+ and Sr2+). With Cu2+, the sensor UNA-1 gave a distinct color change from colorless to dark yellow by forming a complex of 1:1 stoichiometry. Furthermore, sensor UNA-1 was successfully utilized in the preparation of test strips and supported silica for the detection of Cu2+ ions from aqueous environment.
Molecular and crystal structure of 5,6-diamino-1-methyluracil and 5,6-diamino-1,3-dimethyluracil monohydrate. Semiempirical calculations (AM1 and PM3) on 5,6-diaminouracil derivatives
Hueso-Urena, Francisco,Moreno-Carretero, Miguel N.,Low, John N.,Masterton, Alison G.
, p. 133 - 141 (1997)
The crystal and molecular structures of 5,6-diamino-1-methyluracil and 5,6-diamino-1,3-dimethyluracil monohydrate have been determined from X-ray diffraction. Both compounds are planar and the two amino groups have two different conformations. The substituent at the 5 position seems to be a true primary amino group with a strongly sp3 nitrogen, whereas the one at the 6 position is nearly coplanar with the uracil ring, displaying a predominant sp2 character. Semiempirical calculations were made on 5,6-diaminouracil, 5,6-diamino-2-thiouracil and their endocyclic N-methylated derivatives using the AM1 and PM3 hamiltonians. These indicate that the stability decreases on increasing methylation, the 2-thio compounds always being less stable than the 2-oxo ones.
Linagliptin intermediate compound IV
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Paragraph 0188-0189, (2020/09/09)
The invention belongs to the field of pharmaceutical chemicals, and discloses a linagliptin intermediate IV and a novel route for synthesizing an important linagliptin intermediate from the linagliptin intermediate IV. The linagliptin intermediate IV synthesized in the invention has the advantages of high yield, simple operation, substantial reduction of production cost, suitableness for industrial production; and the synthesis route solves the problems of self-coupling of linagliptin intermediates and generation of large impurities in the prior art.
Linagliptin intermediate compound V
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Paragraph 0185-0186, (2020/09/09)
The invention belongs to the field of pharmaceutical chemicals, and provides a linagliptin intermediate compound V and an important intermediate for synthesizing linagliptin by using the intermediateV. The method solves the problems of self-coupling of linagliptin intermediates and generation of large impurities in the prior art, and the synthesized novel intermediate compound V has the advantages of high yield, simple operation, significantly reduced production cost, and suitableness for industrial production.