651-06-9

Crystalline Solid

Sulla,Robins,US,1968

An antibacterial

Sulfameter is an antibacterial.

ChEBI: A sulfonamide consisting of pyrimidine having a methoxy substituent at the 5-position and a 4-aminobenzenesulfonamido group at the 2-position.

2-Amino-5-methoxy pyrimidine is obtained having a melting point of about 300°C by condensation of methoxymalonic acid ester with guanidine carbonate in the presence of sodium ethylate. The resultant reaction product is then converted to 2-amino-5-methoxy-4,6-dichloropyrimidine (melting point 216°C to 217°C) by heating this reaction product with phosphorus oxychloride. The dichloro compound is then suspended in water with zinc dust and is tested in the presence of caustic alkaline or carbonates to produce the 2-aminod-methoxy pyrimidine compound, melting point 80°C to 82°C, (benzene).
12.6 g of 2-amino-5-methoxy pyrimidine, 26.4 g of carbethoxy-sulfanilic acid chloride and 50 cc of dry pyridine are heated for 30 minutes with frequent shaking to a temperature of 80°C. The reaction product is then mixed with 200 cc of water and with dilute hydrochloric acid (0.1 N) until the reaction is acid to Congo Red indicator. A precipitate is formed which is then filtered under suction, washed with distilled water, and dried at 150°C. A practically quantitative yield is recovered of 2-(p-carbethoxyaminobenzene-sulfonamido)- 5-methoxypyrimidine, melting point 248°C to 250°C.To hydrolyze the sulfapyrimidine compound, the same is heated at 90°C with 200 cc of 2 N potassium hydroxide solution for about one hour until complete solution is obtained. The resultant solution is then cooled to room temperature (25°C) and acidified with acetic acid to precipitate the hydrolyzed product, which is then recrystallized from dilute acetone admixed with animal charcoal.

Antibacterial

2-Sulfanilamido-5-methoxypyrimidine. A long-acting compound with activity similar to that of sulfadiazine. Binding to plasma proteins is about 75%.

Sulfameter is a sulfonamide antibiotic. Sulfonamides block the synthesis of dihydrofolic acid by inhibiting the enzyme dihydropteroate synthase. Sulfonamides are competitive inhibitors of bacterial para-aminobenzoic acid (PABA), which is required for bacterial synthesis of folic acid. Sulfameter is a dihydrofolate reductase (DHFR) inhibitor. Sulfonamides are active against Gram positive bacteria and Gram negative bacteria. Mode of resistance is via the alteration of dihydropteroate synthase or alternative pathway for folic acid synthesis.