{TAIL ~ The compound} 6, wherein the stereochemistry of the carbon to which R2 and R3 are attached is of {HEAD ~ the S onfiguration} 
{ TAIL ~ The compound } 6 , wherein the stereochemistry of the carbon to which R2 and R3 are attached is of { HEAD ~ the S onfiguration }
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD