Ultrasonic-Assisted Synthesis of Two t-Butoxycarbonylamino Cephalosporin Intermediates on SiO₂

Table 4

Comparison of ¹³C NMR data (4a).

Lee et al. reported (125 MHz, CDCl3)	Synthetic 4a (75 MHz, DMSO-d6)
—	170.86
165.6	165.01
161.4	161.06
160.2	159.34
154.7	135.70
149.6	130.25
131.0	128.16
126.8	126.84, 126.43
125.9	125.29, 124.83
114.2	113.77
81.5	—
68.5	67.28
61.2	59.18
58.3	57.96, 57.86
55.5	55.06
43.6	43.72, 40.33
28.4	28.93
27.4	26.09

Data taken from [4]; this work.