{HEAD ~ Methylation} of {TAIL ~ compound} 3 with iodomethane in the presence of a base, such as sodium hydride, provides N methylated product of structure 5 
of
{ HEAD ~ Methylation } of { TAIL ~ compound } 3 with iodomethane in the presence of a base , such as sodium hydride , provides N methylated product of structure 5
HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH