TABLE 1.

¹³C chemical shifts of standard compounds in aqueous solution at 22 °C

Chemical shifts are expressed in parts per million (ppm) and are accurate to ±0.01 ppm. Spectra were referenced externally to d-[1-¹³C]mannose in ²H₂O. The more intense signal, C-1 of α-d-mannopyranose, was set to 95.54 ppm. To externally reference the chemical shifts reported here to 2,2-dimethyl-2-silapentane-5-sulfonic acid dissolved in ²H₂O, add 1.06 ppm.

	pH	C-1	C-2	C-3	C-4	C-5	C-6
β-d-Glucopyranosea		93.6	73.1	74.4	71.2	73.0	62.2
α-d-Glucopyranosea		97.4	75.8	77.4	71.2	77.5	62.4
α,α-d-Trehalosea		94.8	72.7	74.2	71.3	73.7	62.2
d-Sorbitola		64.1	74.5	71.3	72.7	72.6	64.5
d-Erythrose 4-phosphate (hydrate)b	1.5	90.3	73.8	71.4c	68.0c
d-Erythritol 4-phosphated	∼2	64.2	72.9	72.3c	67.7c
d-Erythritole		64.13	73.44	73.44	64.13
d-Threose 4-phosphate (hydrate)b	4.5	90.8	74.1	70.6c	67.0c
d-Threitol 4-phosphated	∼2	64.1	72.9	71.7c	68.0c
d-Threitole		64.16	73.11	73.11	64.16
d-Erythrulose 4-phosphated	∼2	67.5
l-Prolinea	7.3	176.2	63.0	30.3	25.4	47.9
Betainea	7.3	170.7	68.0	55.1
d-Ribitole		63.86	73.58	73.68	73.58	63.86
Ethylene glycole		64.06	64.06

^a Values reported in Ref. (25).

^b Values reported in Ref. (18).

^c Resonance appears as a doublet arising from ³¹P-¹³C coupling.

^d Dissolved in H₂O and acetic acid spiked with ²H₂O.

^e Dissolved in 99% ²H₂O.