Saponins synthetic

Saponins. Synthetic steroids that are structurally related to saponins have been shown to lower plasma cholesterol in a variety of different species. 

Steroids a large class of of terpenoids (see Ter-penes) including many biologically important compounds, e.g. Sterols (see). Steroid hormones (see). Bile acids (see). Cardiac ycosides (see), Steroid alkaloids (see) and steroid saponins (see Saponins). Synthetic S, e.g. Ovulation inhibitors (see). Anabolic steroids (see) and structurally modified steroid hormones, are pharmacologically important. More than 20,000 S are known, of which about 2 % have some medical significance. 

Saponins. Although the hypocholesterolemic activity of saponins has been known since the 1950s, thek low potency and difficult purification sparked Htde interest in natural saponins as hypolipidemic agents. Synthetic steroids (292, 293) that are structurally related to saponins have been shown to lower plasma cholesterol in a variety of different species (252). Steroid (292) is designated CP-88,818 [99759-19-0]. The hypocholesterolemic agent CP-148,623 [150332-35-7] (293) is not absorbed into the systemic ckculation and does not inhibit enzymes involved in cholesterol synthesis, release, or uptake. Rather, (293) specifically inhibits cholesterol absorption into the intestinal mucosa (253). As of late 1996, CP-148,623 is in clinical trials as an agent that lowers blood concentrations of cholesterol (254). 

Direct injection API-Electrospray MS is capable of analyzing much larger and less volatile substances than either EI/MS or CI/MS. As a result, this method is often used to provide structural information on peptides, proteins, and polymers derived from both natural and synthetic processes it is also useful in the analysis of many natural compounds including molecules such as saponins and flavonol glycosides, derived from plants. When using direct injection API-electrospray, partial purification and EC preparation are performed elsewhere and a collected fraction is dissolved in an appropriate solvent and injected as a bolus into the mass spectrometer (flow or direct injection or syringe infusion). This has an advantage, as the mass... 

When micelles are used, the CE technique becomes a micellar elec-trokinetic chromatography (MEKC) one. Natural surfactants, such as bile salts, digitonin and saponins, optically active synthetic surfactants, e.g., amino-acid derived ones, alkylglycoside-, tartaric acid- and steroidal glucoside-based surfactants, and high-molecular mass or polymerized surfactants, have been used as chiral selectors in In the lat-... 

Saponins appear to lower plasma LDL cholesterol concentration by interfering with cholesterol absorption. Studies in rats and monkeys fed naturally occurring saponins exhibited significant reductions in cholesterol absorption efficiency and an increase in fecal cholesterol excretion (Malinow et al., 1981 Nakamura et al., 1999 Sidhu et al., 1987). Decreased bile acid absorption and increased excretion has also been reported in animals fed saponins (Malinow et al., 1981 Nakamura et al., 1999 Stark and Madar, 1993). One possible mechanism of action for decreased cholesterol absorption is the ability of saponins to form insoluble complexes with cholesterol (Gestetner et al., 1972 Malinow et al., 1977). In an effort to isolate the specific properties of saponins, Malinow (1985) prepared a variety of synthetic saponins in which the complex carbohydrate moieties of native plant saponins were replaced with simplified carbohydrates such as glucose or cellobiose. One of these synthetic saponins, tiqueside (Pfizer, Inc.), can effectively precipitate cholesterol from micelle solutions in vitro and inhibit cholesterol absorption in a variety of animals (Harwood et al., 1993) and in humans (Harris et al., 1997). But despite ample data showing the formation of a saponin/cholesterol complex in vitro, there is essentially no definitive evidence that complexation occurs in the intestinal lumen (Morehouse et al., 1999). 

Harwood, H.J., Jr., Chandler, C.E., Pellarin, L.D., Bangerter, F.W., Wilkins, R.W., Long, C.A., Cosgrove, P.G., Malinow, M.R., Marzetta, C.A., Pettini, J.L., Savoy, Y.E., and Mayne, J.T. 1993. Pharmacologic consequences of cholesterol absorption inhibition Alteration in cholesterol metabolism and reduction in plasma cholesterol concentration induced by the synthetic saponin /Migogenin cellobioside (CP-88818 tiqueside). J. Lipid Res. 34, 377-395. 

Mineral Salts Immunostimulatory adjuvants Lipid particles Particulate adjuvants Mucosal adjuvants Aluminium hydroxide, aluminium phosphate, calcium phosphate Saponins (e.g., QS21), MDP derivatives, bacterial DNA (CpG oligos), LPS, MPL and synthetic derivatives, lipopeptides, cytokines (e.g., GM-CSF, IL-2, IL-12) Liposomes, virosomes, iscoms, cochleates, emulsions (e.g., Freunds adjuvant, SAF, MF59 ) Poloxamer particles, virus-like particles, PLG microparticles Cholera toxin (CT), mutant toxin (e.g., LTK63, LTR72), heat labile enterotoxin (LT), microparticles, polymerized liposomes, chitosan... 

Synthetic surfactants Laureth-9 sodium lauryl sulphate polysorbate 20 and 80 PEG-8 laurate sorbitan laurate glyceryl monolaurate saponins (e.g., Quillaja saponins) membrane interaction extraction of membrane proteins and lipids solubilization of peptides... 

The steroidal saponin osladin (58) was isolated as a sweet principle from the fern Polypodium vulgare L. (Polypodiaceae) nearly 40 years ago [20,28]. However, the original structure proposed was later revised because the synthetic compound produced was not sweet at all [87]. The correct structure of osladin (58) was characterized by single crystal X-ray... 

Harwood HJ, Chandler CE, Pellatin LD, Bangerter FW, Wilkins RW, Long CA, Cosgrove PG, Malinow MR, Marzetta CA, Pettini JL, Savoy YE, Mayne JT (1993) Pharmacologic Consequences of Cholesterol Absorption Inhibition Alteration in Cholesterol Metabolism and Reduction in Plasma Cholesterol Concentration Induced by the Synthetic Saponin /V-Tigogcnin Cellobioside (CP-88818 Tiqueside). J Lipid Res 34 377... 

In a continuing search for adjuvants with enhanced adjuvanticity and low toxicity, some authors have prepared new chemical semi-synthetic saponins and had compared their adjuvant properties with original saponins. 

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