These methods include converting {HEAD ~ the acid} to {TAIL ~ an activated acid} and reacting with one or more molar equivalents of the desired amine 
These methods include converting { HEAD ~ the acid } to { TAIL ~ an activated acid } and reacting with one or more molar equivalents of the desired amine
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH