“…For example, SarCNU 22 was designed by using N -methylglycinamide as a carrier and showed a good selectivity for cancer cells via the extraneuronal monoamine transporter (EMT) . Although SarCNU showed better efficacy than carmustine against gliomas, , it caused severe pulmonary toxicity in phase II trials and is not approved by the U.S. FDA. , Other compounds, including ranimustine 23 , nimustine 24 , and fotemustine 25 , are approved to be used in Japan, Japan/China, and Europe, respectively. However, they have not gained approval from the U.S. FDA …”