Journal of Oil Palm Research Vol. 12 No. 1, June 2000, p. 102-106
FATTY ACYL SUBSTITUENT-INDUCED CHANGES IN C-CHEMICAL SHIFTS OF CARBONYL CARBONS: A TOOL FOR STRUCTURAL ELUCIDATION IN ACETYLATED GLUCOSE ESTERS OF PALM FATTY ACID
Substituent-induced changes (SIC) in 13C-chemical shifts of carbonyl carbon atoms upon interesterification of glucose pentaacetate (GPA) with fatty acid methyl esters (FAME) of stripped palm kernel oil (SPKO), palm oil (PO) and capric (C10) acid, were used to determine the number and positions of the fatty acid substituents on the pyranosyl ring. Results show that SIC on the ring carbon and ring proton atoms are not always consistent with the molecular structures. But SIC on the carbonyl carbon atoms are however unambiquous and consistent with molecular structures of all the products. The analysis of 13C-chemical shift changes of carbonyl carbon therefore provides a means to determine the number and positions of fatty acyl groups in polyacetylated glucopyranosesKEYWORDS:
*Chemistry Department, Universiti Putra Malaysia, 43400 UPM
Serdang. Selangor, Malaysia.