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