As nouns the difference between pyrimidine and pyrazolopyrimidine

is that pyrimidine is a diazine in which the two nitrogen atoms are in the meta- positions; it is the basis of three of the bases found in DNA and RNA, thymine, uracil and cytosine while pyrazolopyrimidine is any of a class of sedative and anxiolytic drugs with similar effects to benzodiazepines, their molecules typified by the linked six-sided pyrimidine ring and five-sided pyrazole ring.