1,4-diethynyl-2,5-dipropoxybenzene InChI=1/C16H18O2/c1-5-9-17-15-11-14(8-4)16(18-10-6-2)12-13(15)7-3/h3-4,11-12H,5-6,9-10H2,1-2H benzene, 1,4-diethynyl-2,5-dipropoxy-