Proanthocyanidins, also known as condensed tannins and/or oligomeric flavonoids, occur in
May 8, 2019
Proanthocyanidins, also known as condensed tannins and/or oligomeric flavonoids, occur in many edible plants and have various interesting biological activities. HeLa S3 cell proliferation inhibitory activity of a hydrophobic procyanidin B1 analogue in which the lower-unit was acetylated. Open in a separate window Number 1 The structure of (?)-epigallocatechin gallate (1), (?)-epicatechin (2), (+)-catechin (3), procyanidin B1 (4) and procyanidin B1 peracetate (15). 2. Results and Conversation Our synthetic Epacadostat manufacturer methodologies are easily relevant to numerous procyanidin oligomers such as the 3- 0.001, ** 0.005 DMSO-treated groups. On the basis of these results, the upper unit of the dimeric procyanidins are considered to become the more crucial part for the inhibitory activity. In addition, compounds 14 and Epacadostat manufacturer 15, which have hydrophobic lower-units, showed strong inhibitory activity against cell proliferation. These results suggest that the biological activities of proanthocyanidins depend not only on the number of phenolic hydroxyl organizations but also on numerous factors such Epacadostat manufacturer as their constructions, hydrophobic properties, and hydrophilic properties. As was the case for epicatehin-(4-8)-epigallocatechin gallate (21), moderate inhibitory activity was observed. This activity is definitely believed to be because of the influence of the gallic acid moiety. 3. Experimental 3.1. General All commercially available chemicals for chemical synthesis were used without further purification. All reactions were performed under an argon atmosphere and monitored using thin-layer chromatography (TLC) with 0.25-mm pre-coated silica gel plates Merck 60F254 Art 5715. An ATAGO AP-300 spectrometer was used to measure optical rotation 1H-NMR spectra were recorded on a Agilent Inova 500 Spectrometer (500 MHz) and an Agilent DD2 NMR Spectrometer (400 MHz). A JEOL JMS-AX500 mass spectrometer was used to acquire fast atom bombardment (FAB) mass spectra. The human being cervical adenocarcinoma cell collection, HeLa-S3 (RCB0191), was provided by the RIKEN BRC through the National Bio-Resource Project of the MEXT, Saitama, Japan. Synthesized compounds were dissolved in dimethyl sulfoxide (DMSO) and stored at C25 C. 3.2. Synthesis (8) A solution of 7  (13.3 mg, Rabbit Polyclonal to Elk1 0.011 mmol) in THF/MeOH/H2O (20:1:1, 11 mL) was hydrogenated over 20% Pd(OH)2/C (2 mg) for 12 h at RT. Filtration and concentration afforded a pale brownish solid, which was purified with preparative TLC to give 8.7 mg (0.011 mmol, 94%) of 8 as an amorphous solid. Because of NMR spectra broadening, compound 8 was acetylated relating to a general process and then recognized . (11) To a solution of 9 (342 mg, 0.46 mmol) and 10 (1.35 g, 1.84 mmol) in CH2Cl2 (100 mL) SnCl4 (0.69 mL, 0.69 mmol, 1.0 M solution in CH2Cl2) was added dropwise in the presence of MS3? at 0 C. After stirring for 5 min, the pale yellow reaction combination was quenched with saturated NaHCO3. The combination was extracted with CHCl3 and the organic phase was washed with water and brine, and then dried (Na2SO4). Filtration, concentration, and preparative silica gel TLC purification (hexane/EtOAc, 4:1) afforded 246 mg (0.18 mmol, 39%) of 11 like a colorless amorphous compound: +56.4 (1.93, CHCl3); 1H-NMR (500 MHz, CDCl3, 0.8 : 0.2 mixture of rotational isomers) major isomer: 7.46-6.94 (18.4H, m), 6,71 (0.8H, d, = 8.5 Hz), 6.49 (0.8H, d, = 2.2 Hz), 6.39 (0.8H, dd, = 2.2, 8.5 Hz), 6.12 (0.8H, s), 6.01 (0.8H, d, = 2.2 Hz), 5.64 (0.8H, d, = 2.2 Hz), 5.26C4.56 (0.8H, m), 3.96C3.95 (0.8H, m), 3.83-3.80 (0.8H, m), 3.65 (0.8H, d, = 8.5 Hz), 3.67 (0.8H, dd, = 6.0, 16.5 Hz), 2.52 (0.8H, dd, = 8.9, 16.5 Hz), 1.70 (0.8H, d, = 6.5 Hz), 1.33 (0.8H, d, = 3.0 Hz), 1.04 (7.2H, s), 0.97 (7.2H, s), 0.95 (7.2H, s), 0.86 (7.2H, s), 0.30 (3H, s), 0.29 (3H, s), 0.26 (3H, s), 0.19 (3H, s), 0.16 (3H, s), 0.15 (3H, s), 0.04 (3H, s), 0.02 (3H, s); small isomer: 7.46C6.94 (4.8H, m), 6.78 (0.2H, d, = 2.2 Hz), 6.65 (0.2H, d, = 2.2 Hz), 6.29 (0.2H, d, = 2.2 Hz), 6.20 (0.2H, d, = 2.2 Hz), 5.96 (0.2H, s), 5.33C4.54 (2H, m), 3.95C3.98 (0.2H, m), 3.89C3.88 (0.2H, m), Epacadostat manufacturer 3.63C3.61 (0.2H, m), 3.57C3.50 (0.2H, m),.