Microbiologic and pharmacologic properties of a new ampicillin derivative: Ampicillin-guaiacolsulfonate.

Ampicillin-guaiacolsulfonate, a new derivative of ampicillin, preserves the antibacterial properties of ampicillin, is suitable for infection owing to its good water solubility and it has far higher stability in dry state than has sodium ampicillin. Ampicillin-guaiacolsulfonate is better orally absorbed in rabbit than is ampicillin. In vitro experiments carried out with the model system by Rosano and Schulman, and measurements of the intestinal absorption in the everted sac jejunal preparation, carried out with 14C-labelled compounds, demonstrate that the new ampicillin derivative is better absorbed by the intestine because of an increase in the intestinal permeability of the molecule itself.