Journal of Lipids

Research Article

Novel Conjugates of 1,3-Diacylglycerol and Lipoic Acid: Synthesis, DPPH Assay, and RP-LC-MS-APCI Analysis

Table 2

Linear formula of LA, DHLA, DOLA, and DODHLA, retention time (RT, minutes), mono isotopic mass and HPLC-MS-APCI data.


Compound	RT (min)	Monoisotopic mass	Ions (m/z)	Suggested molecular ions/fragments	Relative intensity of ions (%)

LA^a C₈H₁₄O₂S₂	3.47	206.04	205 [M–H]⁻	[M–H]⁻	100
			171 [M–34–H]⁻	[M–H₂S–H]⁻	6
			411 [2M–H]⁻	[2M–H]⁻	6
DHLA^b C₈H₁₆O₂S₂	3.46	208.06	207 [M–H]⁻	[M–H]⁻	72
			173 [M–34–H]⁻	[M–H₂S–H]⁻	3
			205 [M–2H–H]⁻	[M–2H–H]⁻	100
			171 [M–2H–34–H]⁻	[M–2H–H]⁻	15
DO^c C₃₉H₇₂O₅	15.13	620.54	621 [M+H]⁺	[M+H]⁺	3
			603 [M–18+H]⁺	[M–H₂O+H]⁺	100
			339 [M–282+H]⁺	[M–R₁COOH+H]⁺	80
DOLA^d C₄₇H₈₄O₆S₂	17.68	808.57	809 [M+H]⁺	[M+H]⁺	100
			603 [M–206+H]⁺	[M–R₂COOH+H]⁺	2
			527 [M–282+H]⁺	[M–R₁COOH+H]⁺	7
			339 [M–206–282+18+H]⁺	[M–R₁COOH–R₂COOH+H₂O+H]⁺	3
			826 [M+17+H]⁺	Unidentified adduct	7
DODHLA^e C₄₇H₈₆O₆S₂	17.05	810.59	811 [M+H]⁺	[M+H]⁺	26
			793 [M–18+H]⁺	[M–H₂O+H]⁺	15
			603 [M–208+H]⁺	[M–R₃COOH+H]⁺	76
			529 [M–282+H]⁺	[M–R₁COOH+H]⁺	100
			339 [M–208–282+18+H]⁺	[M–R₃COOH–R₁COOH+H₂O+H]⁺	35
			828 [M+17+H]⁺	Unidentified adduct	13

^aLA: α-lipoic acid; ^bDHLA: dihydro lipoic acid; ^cDO: 1,3-dioleoyl-sn-glycerol; ^dDOLA: 1,3-dioleoyl-2-lipoyl-sn-glycerol; ^eDODHLA: 1,3-dioleoyl-2Dihydrolipoyl-sn-glycerol;
*R₁COOH = oleic acid general formula; R₂COOH = α-lipoic acid general formula; R₃COOH = dihydrolipoic acid general formula.