SYNTHESIS AND CYTOTOXIC STUDIES OF 5-O-(BETA-GLUCOPYRANOSYL)-2-NITROBENZYL CAGED L-LEUCYL-L-LEUCINE METHYL-ESTER WITH INCREASED SOLUBILITY IN PBS CONTAINING 1-PERCENT DMSO

We report the synthesis of a new type of a caged L-leucyl-L-leucine me thyl ester, a sugar derivative 2, and study its photochemical and immu nological properties. Compared with those of the previously reported o -nitrobenzyl caged compound, 1, and another new 4, 5-dimethoxy-2-nitor obenzyl caged compound 3, 2 was found to be almost 30 times more solub le in PBS containing 1% DMSO, and released leucyl-leucine methyl ester upon irradiation more efficiently than 1. Efficiency of induction of apoptosis of HL60 cells by irradiation of a solution containing 2 was only slightly lower than that by leucyl-leucine methyl ester itself. ( C) 1997 Academic Press.