“…N -Cyclohexyl-2,5-dimethyl-3,4-bis(3-formyl-2-methylphenyl)pyrrole (24). Chromatography (dichloromethane/ n -hexane (1:1)) on silica gel gave colorless crystals of 24 (89%): mp 162−164 °C; 1 H NMR 10.25, 10.21 (s, ratio 1:1, total 2H), 7.0−7.7 (m, 6H), 3.87−4.20 (m, 1H), 2.32, 2.46 (s, ratio 1:1, total 6H), 2.09, 2.12 (s, ratio 1:1, total 6H), 2.04 (br s, 10H); IR (KBr) 1685 (CO) cm -1 ; MS m / z 413 (M + , 100), 398 (12), 385 (23), 370 (13), 331 (13), 316 (12), 303 (16). Anal.…”