6H, s), 2.ten (6H, s), two.14 (4H, t, J = 7.three Hz), 2.30 (4H, m), two.44 (4H, 6H46N4O6) two,2-(1,2Ethanediyl)bis[5-(ethoxycarbonyl)-4-methyl-1H-pyrrole-3-propanoic acid] (13217 mg, 0.49 mmol) was dissolved in 30 cm3 CH3OH within a 100 cm3 round bottom flask. To this remedy had been added 209 mg 5-q, J = 7.0 Hz), two.48 (4H, t, J = 7.three Hz), 2.79 (4H, s), five.93 (2H, s), 9.84 (2H, brs), 10.12 (2H, brs) ppm; 13C NMR data in Table 2; UV-Vis data in Table four; CD data in Table eight.NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author ManuscriptMonatsh Chem. Author manuscript; out there in PMC 2015 June 01.Pfeiffer et al.Web page(4Z,15Z)-2,two -(1,2-Ethanediyl)bis[5-[(3-ethyl-1,5-dihydro-4-methyl-5-oxo-2H-pyrrol-2ylidine)methyl]-4-methyl-1H-pyrrole-3-butanoic acid] dimethyl ester (2eC38H50N4O6)NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript2,2-(1,2-Ethanediyl)bis[5-(ethoxycarbonyl)-4-methyl-1H-pyrrole-3-butanoic acid] (14686 mg, 1.53 mmol) was dissolved in 30 cm3 CH3OH within a 100 cm3 round bottom flask to which 662 mg 5-(bromomethylene)-3-pyrrolin-2-one (153.07 mmol) and three? drops aq. HBr have been added. The resulting mixture was stirred and heated at reflux for 20 h, throughout which a green strong developed within the reaction mixture. The strong was isolated by filtration and characterized as the preferred product 2e. Yield: 250 mg (25 ); m.p.: 239?40 ; 1H NMR: = 1.09 (6H, t, J = 7.0 Hz), 1.20 (6H, s), 1.85 (4H, quint, J = 7.0 Hz), two.ten (6H, s), 2.32 (4H, q, J = 7.two Hz), 2.41 (4H, t, J = 7.2 Hz), 2.52 (3H, t, J = 7.2 Hz), 3.12 (4H, s), three.70 (6H, s), five.86 (2H, s), ten.27 (2H, brs), 11.03 (2H, brs) ppm; 13C NMR information in Table 1. (4Z,15Z)-2,two -(1,2-Ethenediyl)bis[5-[(3-ethyl-1,5-dihydro-4-methyl-5-oxo-2H-pyrrol-2ylidine)methyl]-4-methyl-1H-pyrrole-3-propanoic acid] dimethyl ester (3eC36H44N4O6) Homorubin dimethyl ester 1e (40 mg, 0.063 mmol) was dissolved in 30 cm3 THF beneath an N2 atmosphere. Then 14 mg DDQ (0.061 mmol) in five cm3 THF was added, as well as the mixture was stirred for 60 min. The reaction mixture was then poured into 100 cm3 ice-cold water containing 100 mg ascorbic acid. The resulting mixture was extracted with CH2Cl2 (three ?75 cm3). The combined CH2Cl2 extractions were washed with saturated aq. NaHCO3, dried more than sodium sulfate, and evaporated to provide crude 3e. The crude product was purified utilizing radial chromatography applying 99:1 CH2Cl2:CH3OH (by vol).1314649-82-5 structure Yield: 33 mg (81 ); m.RockPhos Pd G3 Chemscene p.PMID:24563649 : 250 (dec); IR (KBr): V = 3424, 2942, 2355, 1734, 1654, 1625, 1460, 1260, 1160 cm-1; 1H NMR: = 1.ten (6H, t, J = 7.5 Hz), 1.95 (6H, s), two.05 (6H, s), two.50 (4H, q, J = 7.two Hz), two.50 (4H, t, J = 7.five Hz), two.80 (4H, t, J = 7.five Hz), three.60 (6H, s), five.90 (2H, s), six.90 (2H, s), ten.20 (2H, brs), 10.30 (2H, brs) ppm; 13C NMR information in Table three; UV-Vis information in Table 5; FABHRMS: exact mass calculated for C36H44N4O6 628.3261, discovered 628.3254. (4Z,15Z)-2,two -(1,2-Ethenediyl)bis[5-[(3-ethyl-1,5-dihydro-4-methyl-5-oxo-2H-pyrrol-2ylidene)methyl]-4-methyl-1H-pyrrole-3-propionic acid] (3C34H40N4O6) In a 25 cm3 round bottom flask 20 mg 1 (0.033 mmol) was dissolved in 10 cm3 distilled dimethyl sulfoxide. DDQ (17 mg, 0.083 mmol) in 2 cm3 dimethyl sulfoxide was added at after, plus the remedy was allowed to stir for 30 min (upon addition with the DDQ the answer immediately turned a blue color). The solution was poured into 50 cm3 ice water containing one hundred mg ascorbic acid, and also a precipitate formed. The precipitate was separated and washed by centrifugation and isolated by filtration. The solid was dri.