Galactosyl Derivatives of <scp>l</scp>-Arginine and <scp>d</scp>-Arginine: Synthesis, Stability, Cell Permeation, and Nitric Oxide Production in Pituitary GH<sub>3</sub> Cells
levels in the cells by increasing the cellpermeation of its precursors. To this aim, two galactosyl prodrugs, L-arginine-D-galactos-6'-yl ester (L-ArgGal) and D-arginine-D-galactos-6'-yl ester (D-ArgGal) were synthesized. Remarkably, using the HPLC-ESI/MS technique, we found that L-ArgGal and D-ArgGal prodrugs both increased the concentration levels of L- and D-arginine and their derivatives in pituitary