نتایج جستجو برای: hydroxy pyrimidines
تعداد نتایج: 37472 فیلتر نتایج به سال:
A new synthetic route leading to functionalized 1H-1,2,3-triazole-4-carbonitriles has been developed. set of 1-aryl-5-methyl-1H-1,2,3-triazole-4-carbonitriles was obtained in high yields from readily available starting 1H-1,2,3-triazole-4-carboxylic acids via several protocols. Synthesized were examined as promising precursors the simple and efficient method for preparation 2-triazol-4-yl-thien...
o-Aminonitrile or o-aminoester compounds were cyclized to fused pyrimidines by reacting with ethyl iso(thio)cyanatoacetate in pyridine, and then were methylated, halogenated and subsequently displaced by the amines studied.
A series of 21 substituted pyrazolo[3,4-d]pyrimidines-4-amines were studied by (1)H and (13)C NMR. The application of two-dimensional techniques, HMQC and HMBC, allowed the complete assignment of the spectra for all the compounds.
A novel one-flask synthetic method was developed in which 5-aminopyrazoles were reacted with N,N-substituted amides in the presence of PBr₃. Hexamethyldisilazane was then added to perform heterocyclization to produce the corresponding pyrazolo[3,4-d]pyrimidines in suitable yields. These one-flask reactions thus involved Vilsmeier amidination, imination reactions, and the sequential intermolecul...
A series of mono-pyrrolo[2,3-d]pyrimidines 4a-4k, unsymmetrical bis-purine isosteres 5a-5e and symmetrical bis-pyrrolo[2,3-d]pyrimidines 6a and 6b connected via di(1,2,3-triazolyl)phenyl linker were synthesized by click chemistry. Whereas mono- 4g and bis-pseudopurine 5e showed selective inhibitory activities on cervical carcinoma (HeLa) cells, bis-pyrrolo[2,3-d]pyrimidine 6b exhibited potent a...
A number of new functionalized 4,5-dihydropyrazolo[1,5- a ]thieno[3,2- e ]pyrimidine derivatives were obtained by the domino reaction thienylhydrazonyl chlorides with (1,2,4-oxadiazol-5-yl)acetonitrile. In organic synthesis, much attention has been recently paid to tandem and reactions. The advantage such reactions concerns high selectivity, ease performance, reduction intermediate steps, atom ...
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