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The self consistent (pi)electron densities required for the ground state ofpyrimidines are 0.776, 0.825 and 1.103 for positions 2, 4 and 5 respectively 144 .Despite considerable localization of (pi) electrons at nitrogen atoms of pyrimidinesthe ring system is still sufficiently aromatic to possess substantial stability. This hasa great advantage in the primary synthesis of pyrimidines.NNNN(2) (2a) (2b) (2c)HNN+N+NHN.+ N +N.NNN.NN.++(2d) (2e) (2f) (2g)The first primary synthesis from aliphatic fragments was carried out byFrankland et al. in 1848. Since then a many distinct primary synthetic methods havebeen devised. 145-154 It is also possible to prepare pyrimidines from other heterocycliccompounds such as pyrrole 155 , imidazole 156 , isoxazole and oxazole 157-158 ,pyridine 159 , pyrazine 160 , 1,3,5-triazine 161 , oxazine 162 , thiazine 163by differentprocesses.SYNTHETIC METHODS FOR PYRIMIDINESVarious methods for synthesis of pyrimidines which are reported in theliterature are as follows.(a) By the condensation of urea and malonic acid led to formation ofpyrimidine. 16443Pyrimidine…..