Problem to use mongosh with --eval option

PARAM2=“var param1=${Dbname}, param4=${appDB}, param5=‘${ADMIN_PWD}’”

mongosh ${DB_URI} -u ${ADMIN_USER} -p ${ADMIN_PWD} --quiet --eval “${PARAM2}” ${JS_DIR}/createDB.js 2>&1 1>> ${scriptlog}

doesn’t work.
can you hepl me please to apply the good syntaxe