129298-91-5 AGM-1470 Carbamic acid, (chloroacetyl)-, (3R,4S,5S,6R)-5-methoxy-4-[ (2R,3R)-2-methyl-3-(3-methyl-2-butenyl)oxiranyl]-1-oxaspiro[2.5]oct-6-yl ester NSC642492 TNP-470