Of these, {HEAD ~ the esters} of acetic acid, especially acetic acid methyl esters and {TAIL ~ ethyl esters}, are particularly preferred 
Of these , { HEAD ~ the esters } of acetic acid , especially acetic acid methyl esters and { TAIL ~ ethyl esters } , are particularly preferred
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH