{HEAD ~ An initial attempt} of protection by acylation of sulfhydryl group resulted in maintaining {TAIL ~ duration} of the activity to some extent 
resulted in maintaining
{ HEAD ~ An initial attempt } of protection by acylation of sulfhydryl group resulted in maintaining { TAIL ~ duration } of the activity to some extent
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH