Harwood Acylglycerols glycerides

Acylglycerols are esters of glycerol (propane-1,2,3-triol) and fatty acids. Partial glycerides are important intermediates in metabolism and triacylglycerols are the major constituents of natural fats and oils. 

Any glycerolipid will be chiral when the substituents at the sn and sn- positions are different. Mirror-image molecules or enantiomers possess opposite but equal optical rotations. However, if both substituents are long-chain acyl groups then the optical rotation will be extremely small (Myher, 1978). 

These are fatty acid monoesters of glycerol and exist in two isomeric forms  

These are fatty acid triesters of glycerol. The fatty acids may be all different, two different or all alike. 

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