reacting the cellulose activate with {TAIL ~ an acetylating agent} in {HEAD ~ the presence} of the acetylating catalyst and acetylating solvent, 
reacting the cellulose activate with { TAIL ~ an acetylating agent } in { HEAD ~ the presence } of the acetylating catalyst and acetylating solvent ,
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH