(1R,11R,12R,14R,19S)-12-methoxy-17,17-dimethyl-6-nitro-2,13,16,18-tetraoxa-10-azatetracyclo[9.8.0.03,8.014,19]nonadeca-3(8),4,6-trien-9-one 以99%的产率得到(1R,3R,4S,4aR,11aR)-4-Hydroxy-3-hydroxymethyl-1-methoxy-8-nitro-4,4a,11,11a-tetrahydro-1H,3H-2,5-dioxa-11-aza-dibenzo[a,d]cyclohepten-10-one