127-79-7

White Solid

Sulfamerazine,Lederle,US,1943

Antibacterial.

ChEBI: A sulfonamide consisting of pyrimidine with a methyl substituent at the 4-position and a 4-aminobenzenesulfonamido group at the 2-position.

To a well agitated solution of 6.95 grams of 2-amino-6-methyl pyrimidine in 40 cc of pyridine, 15 grams of p-acetylaminobenzenesulfonyl chloride are added in small portions over a 30 minute period. The reaction mixture is then heated on a steam bath for 30 minutes, the free pyridine being then removed under reduced pressure and the residue mixed with cold water, and the latter mixture is vigorously stirred. The solid reaction product is removed by filtration and washed with cold water.
There is obtained a yield of 14 grams of crude 2-(pacetylaminobenzenesulfonamido)- 6-methyl pyrimidine, which on recrystallization from alcohol and water melts at 238° to 239°C. The crude product is hydrolyzed by suspending it in 400 cc of 2 N hydrochloric acid and warming until solution is complete. The solution is neutralized with sodium carbonate and the precipitated 2-(sulfanilamido)-6-methyl pyrimidine is removed by filtration. The latter on recrystallization from alcohol and water shows a melting point of 225° to 226°C.

Antibacterial

Like all examined sulfanilamides, this drug is effective in treating infections caused by streptococci, gonococci, pneumococci, staphylococci, and also colon bacillus. Synonyms of this drug are dosulfin, polagin, romezin, and others.

2-Sulfonamido-4-methylpyrimidine. A component of some triple sulfa combinations. Plasma half-life is c. 24 h and protein binding c. 75%. It is less active than sulfadiazine.

Sulfamerazine, N1 -(4-methyl-2-pyrimidinyl)sulfanilamide (33.1.12), is also synthesized in the manner described above, which is by reacting 4-acetylaminobenzenesulfonyl chloride with 2-amino-4-methylpyrimidine (33.1.10), which is in turn synthesized by the traditional scheme of synthesizing derivatives of pyrimidine. Acetoacetic ester is condensed with guanidine to give 4-methyl-2-aminopyrimidin-6-one (33.1.8). Reacting this with phosphorous oxychloride gives 4-methyl-2-amino-6-chloropyrimidine (33.1.9). The chlorine atom at C6 of the pyrimidine ring is then removed by reduction with hydrogen using a palladium on carbon catalyst. The resulting 4-methyl-2-aminopyrimidine (33.1.10) is then reacted with 4-acetylaminobenzenesulfonyl chloride to make an acetanilide derivative (33.1.11), the subsequent hydrolysis of which with base leads to the formation of the desired sulfamerazine.

Store at -20°C