A Validated ¹H NMR Method for the Quantitation of 5-Hydroxymethyl-2(5H)-Furanone, a Valuable Chemical Intermediate, In a Dichloromethane Extract of Helleborus lividus subsp: Corsicus Leaves from Corsica

Table 3

Precision of 5-hydroxymethyl-2(5H)-furanone (F) measurements by ¹H NMR.

	Signal at 6.16 ppm (H2)					Signal at 7.50 ppm (H3)
	Test 1	Test 2	Test 3	Test 4	Test 5	Test 1	Test 2	Test 3	Test 4	Test 5
Weighted mass of F (mg)	30.51	30.51	30.51	30.51	30.51	30.51	30.51	30.51	30.51	30.51
F area	3.32	3.31	3.31	3.32	3.31	3.32	3.31	3.31	3.32	3.32
Calculated mass of F (mg)	30.58	30.49	30.49	30.58	30.49	30.58	30.49	30.49	30.58	30.49
RE (%)	0.23	−0.07	−0.07	0.23	−0.07	0.23	−0.07	−0.07	0.23	−0.07

The area of the signal of the aldehydic proton of vanillin is fixed at 1.00 in all experiments; F area: area of the selected signals of 5-hydroxymethyl-2(5H)-furanone; mass of vanillin: 12.60 mg; calculated mass according to formula (1); RE: relative error.