Saponins were purified from Quillaja saponaria Molina bark by silica and reverse phase chromatography. The resulting purified saponins were tested for adjuvant activity in mice. Several distinct saponins, designated QS-7, QS-17, QS-18, and QS-21, were demonstrated to boost antibody levels by 100-fold or more when used in mouse immunizations with the Ag BSA and beef liver cytochrome b5. These purified saponins increased titers in all major IgG subclasses. To determine optimal dose in mice for adjuvant response, QS-7 and QS-21 were tested in a dose-response study in intradermal immunization with BSA in mice; for both of these purified saponins, adjuvant response (determined by stimulation of ELISA titers to BSA) neared maximum at doses of 5 micrograms and was shown to plateau up to the highest dose tested, 80 micrograms. These purified saponins vary considerably in their toxicity, as assessed by lethality in mice; the main component, QS-18, being the most toxic. Saponins QS-7 and QS-21 showed no or very low toxicity in mice, respectively. None of these saponins stimulated production of reaginic antibodies. The monosaccharide composition of these saponins showed similar but distinct compositions with all four containing fucose, xylose, galactose and glucuronic acid. Predominant differences were observed in the quantities of rhamnose, arabinose, and glucose. Monomer m.w. (determined by size exclusion HPLC) were determined to range from 1800 to 2200.
The title compound, C(20)H(16)N(2)O, has two molecules in the asymmetric unit and the crystal structure shows that the central pyridine ring of each molecule has a flat boat conformation. The terminal C atom in one of the molecules is disordered over two positions, with relative occupancies of 0.594 (14) and 0.398 (14). Intermolecular C-H.N and C-H.pi interactions and pi-pi stacking, along with intramolecular C-H.N and C-H.pi interactions, help to stabilize the structure.
Silver(I) and copper(II) complexes of 4-amino-N-(4,6-dimethyl-2-pyrimidinyl)benzenesulfonamide (smz) have been synthesized and characterized by elemental analysis and infrared, 1 H-NMR and UV-Vis spectroscopy. [Ag(smz)(pyridine)] (1) crystallizes in monoclinic system with space group P2 1 /c and Z = 4 while [Cu(smz) 2 (pyridine) 2 ]·H 2 O (2) crystallizes in triclinic system with space group P-1 and Z = 2. X-ray analysis revealed that silver in 1 is four-coordinate exhibiting distorted tetrahedral geometry while copper in 2 is coordinated to six nitrogens leading to a highly distorted octahedral geometry. The molecular structures of both 1 and 2 are stabilized by N-H…O and C-H…π intermolecular and C-H…O intramolecular interactions. Water plays a significant role in crystal packing by forming strong N-H…O water intramolecular as well as O water -H…N intermolecular interactions in 2. The results of IR, UV-Vis, 1 H NMR spectral data and thermal analysis for 1 and 2 suggest that the binding of silver and copper to the sulfonamidic nitrogen is in agreement with the crystal structure determination.Antimicrobial activities of silver (1) and copper (2) complexes of sulfamethazine are studied by the dilution method against Staphylococcus aureus and Escherichia coli strains.
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