R14 is {TAIL ~ hydrogen}, nitro, {HEAD ~ cyano} or C1 4 alkylcarbonyl; and 
R14 is { TAIL ~ hydrogen } , nitro , { HEAD ~ cyano } or C1 4 alkylcarbonyl ; and
OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH