604835 Disclosed herein is a compound of formula 1, wherein the compound is 3-(2-pyridylthio) propionic acid butyl ester, 3-(2-pyridylthio) propionic acid pentyl ester, and 7-(2-pyridylthio) heptanolc acid ethyl ester； or wherein R1 is H, R2 is COOMe, R3 is (CH2)nCOOR4, R4 is C2H5,C3H7, C4H9, C5H11, C6H11 and n is 1–7. Additionally disclosed is a process for preparing a compound of formula 1 comprising irradiating Barton ester with sun light； and the compound for inhibiting ICAM-1 (intercellular cell adhesion molecule-1) expression.
