FLUORESCENT MOLECULAR PROBES .1. THE SYNTHESIS AND BIOLOGICAL PROPERTIES OF AN ELF(R) BETA-GLUCURONIDASE SUBSTRATE THAT YIELDS FLUORESCENT PRECIPITATES AT THE ENZYMATIC-ACTIVITY SITES

A novel quinazolinone-based fluorogenic beta-glucuronidase substrate h as been synthesized and evaluated. In this protocol, a partially prote cted salicyl glucuronide is oxidatively condensed with anthranilamide to afford the required quinazolinonyl glucuronic acid methyl ester tha t is readily deprotected to yield the desired glucuronide, known as EL F(R)-97 glucuronide. The glucuronide is a sensitive fluorogenic beta-g lucuronidase substrate that yields a bright yellow-green fluorescent p recipitate upon enzymatic reaction. (C) 1997 Elsevier Science Ltd.