Purines, consisting of adenine and guanine, are double-ringed bases in DNA and RNA; pyrimidines, which include cytosine, thymine, and uracil, are single-ringed.
In the present description, the term “alkyl” refers to straight- or branched-chain hydrocarbons having from 1 to 10 carbon atoms and more preferably 1 to 8 carbon atoms which include, by way of example, methyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl and the like. The alkyl gr...
Thus, in another aspect, the present invention provides methods for treating proliferative diseases such as cancer and which include administering therapeutically effective amounts of such compounds to the patients. The following abbreviations and definitions are used throughout this application (Table 1...
Nitrogenous bases are organic molecules bound to nitrogen are building blocks of nucleotide monomers, which in turn forms DNA and RNA polymers. There are two groups of nitrogenous bases: purines, and pyrimidines. Purine bases ...
Which of the following nitrogenous bases is not found in DNA? (a) Adenine (b) Thymine (c) Uracil (d) Cytosine (e) Guanine. Which RNA base pairs with the adenine in DNA? A. Thymine B. Cytosine C. Both A and B D. Uracil DNA nucleotides include ___. (a) Uracil...
11. Architecture The lowest part of a structure, such as a wall, considered as a separate unit: the base of a column. 12. Heraldry The lower part of a shield. 13. Linguistics A morpheme or morphemes regarded as a form to which affixes or other bases may be added. 14. Mathematics ...
R2and R3independently of each other have the definition given to R1; R2and R3together form a 5 to 7 membered ring which is partially or fully unsaturated and can be interrupted by one or more atoms selected from the group consisting of nitrogen, oxygen and sulfur, wherein the oxygen atoms...
the core structure ofpyrrole[2,3-d]pyrridimines involves the Sonogashira reaction fol-lowed by tandem cyclization in one or two pot manner(Scheme 1).2,6This method suffers from low reaction yield, espe-cially with steric hindered substrates4,6and requirement of thecostly/toxic Pd catalysts. ...
For purposes of this invention the free bases are equivalent to their non-toxic acid-addition salts. The novel compounds of the present invention where R1 and R2 are both hydrogen in structural formula (I), may be readily prepared as set forth in the following reaction scheme (A). ##STR...
Compounds which are preferred according to the invention include addition products of acids and those pyrazolopyrimidines of the formula (I), in which R1 represents amino and R2, R3, X1 and X2 have the meanings mentioned as being preferred for these radicals. The acids which may be added...