Chemistry of Succinimido Esters. XXI

A sensitive determination of sphingolipid bases (1) was made using synthetic Cn-dihyrosphingosine and naturally occurring C18- (1) aromatized with N-succinimidyl arylacetate (2a). The amino group in (1) easily reacted with (2a) to give the corresponding N-arylacetyl derivative (3a). The isomers of (1) were separated on a normal phase HPLC column in the form of (3a) which was detectable by the absorption in UV region. The isomer content of (1) as determined by the present method using (3a) having a different substituent showed agreement with that determined by GC method in the form of N-acetyl-O, O-bis (TMS) derivatives of (1) and the HPLC method in the form of N-arylcarbonyl derivative of (1), (3b).