After a 60-minute exposure, approximately 80% of the input material remained intact, corresponding to an extrapolated halflife of approximately 200 minutes (figure 3A). Unstable analogs of JMN3-003, JMN5-165 and JMN5-166 (figure S1), returned half lives of 38 and 5 minutes in this assay, respectively, confirming metabolic competency of the S9 fractions used.