Particularly, the carbonate, thionocarbonate, and oxalate cyclic esters are prepared and used as monomers or {HEAD ~ reactants} to prepare {TAIL ~ useful products} 
to prepare
Particularly , the carbonate , thionocarbonate , and oxalate cyclic esters are prepared and used as monomers or { HEAD ~ reactants } to prepare { TAIL ~ useful products }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL