Table 2.

Chemical shifts (ppm) and assignments of Neu5Acα2,3LacβProN₃, the sialylation product catalyzed by H. ducreyi α2,3-sialyltransferase Hd0053.^a

Sugar	Position	H	C
Glc	1	4.46	102.3
	2	3.29	72.9
	3	3.63	74.5
	4	3.64	78.3
	5	3.58	74.9
	6	3.96	60.2
	6'	3.80
Propyl azide	-CH2-CH2-CH2-N3	3.99	67.5
		3.76
	-CH2-CH2-CH2-N3	1.89	28.4
	-CH2-CH2-CH2-N3	3.43	48.0
Gal	1	4.50	102.8
	2	3.55	69.5
	3	4.09	75.6
	4	3.94	67.6
	5	3.69	75.3
	6	3.74	61.2
	6'	3.69
Neu5Ac	1		174.0
	2		99.9
	3ax	1.77	39.8
	3eq	2.73
	4	3.67	68.5
	5	3.84	51.8
	6	3.62	73.0
	7	3.57	68.2
	8	3.88	71.9
	9	3.86	62.7
	9'	3.66
	N-CO-CH3	2.01	22.2
	N-CO-CH3		175.1

^aNMR spectra were recorded at 299 K in D₂O at neutral pH. Chemical shifts (ppm) are given relative to HOD (4.79 ppm) for ¹H NMR or the methyl resonance of the internal deuterated acetone (30.89 ppm) for ¹³C NMR. The peaks were assigned using ¹H-¹H COSY and ¹H-¹³C HSQC with reference to [21].