Appearance and properties: white to light yellow powder

Density: 1.252 g/cm3

Melting point: 199-203 ° C

Boiling point: 526 ° C at 760 mmHg

Flash: DHS 271.9 C

Stability: Stable. Incompatible with strong oxidizing agents, acids.

Storage condition: 2-8 ° C

Trimethoprim is a bacterial dihydrofolate reductase inhibitor, a sulfanilamide synergistic drug. The principle of its antibacterial action is to interfere with folate metabolism of bacteria. It mainly selectively inhibits the activity of dihydrofolate reductase of bacteria, so that dihydrofolate cannot be reduced to tetrahydrofolate, thus inhibiting the growth and reproduction of bacteria. Trimethoprim has antibacterial activity against most gram-positive and gram-negative bacteria. In addition, trimethopridine has a certain effect on plasmodium and some fungi, such as nocardia, protozoa and yeast. Among gram-positive bacteria, streptococcus pneumoniae is sensitive to trimethoprim. Among the gram-negative bacteria, escherichia coli, salmonella, proteus, pneumoniae, dysentery, typhoid and pertussis are sensitive to trimethophenil. Trimethoprim has no antibacterial effect on pseudomonas aeruginosa, meningococci and alkali-producing bacillus.