- Reactions with 2-thiothymine; selective cyclization of S-substituted 2-thiothymine
-
2-Thiothymine (I) undergoes S-alkylation when treated with some halo compounds such as methyl and ethyl iodides. The S-alkyl derivatives II are treated with hydrazine hydrate to produce the hydrazine derivative III, which condensed with p-chlorobenzaldehyde to give p-chlorobenzaldehydepyrimidinehydrazone derivative IV. Compound IIa reacts with phosphorus oxychloride to give 4-chloro derivative V. The chlorine atom in V undergoes nucleophilic substitution with p-chloroaniline and anthranilic acid to produce drivatives VIa,b. Dehydrative cyclization of VIb yields the pyrimido[6,1-b]quinazolin-10-one derivative VII. Treatment of V with ammonia solution gives the diamino derivative VId. Reaction of V with sodium azide produces the tetrazolo[1,5-c]pyrimidine derivative VIII. Compound I undergoes S-alkylation with α-haloketones followed by cyclization to produce the thiazolo[3,2-a]pyrimidine derivatives Xa-c. Reaction of I with bromomalononitrile produces thiazolo[3,2-a]pyrimidine-2-carbonitrile derivative XII. Treatment of XII with formic acid, formamide and ammonium thiocyanate produces thiazolo[3,2-a:4,5-d]dipyrimidine derivatives XIIIa-c. Finally, reacting XII with malononitrile yields ppyrido[2′,3′:4,5]thiazolo[3,2-a]pyrimidine-3-carbonitrile derivative XIV.
- Youssef, Mohamed M.,Youssef, Ayman M. S.
-
-
- Process for preparing substituted 2,4-diaminopyrimidines and isoxazole intermediate
-
A process for the preparation of 2,4-diamino-5-benzylpyrimidines by reacting 4-bromomethylisoxazole with an aromatic compound of the formula STR1 wherein R, R1 and R2 are hydrogen, lower alkoxy and lower alkyl, AND SUBSEQUENTLY TREATING THE REACTION PRODUCT WITH A GUANIDINE SALT, IS DESCRIBED.
- -
-
-