A combination of high-pressure extraction and preparative chromatography was used to purify the group A and group B soyasaponins from soy germ for use as analytical standards and for use in biological assays. A standardized sample preparation and extraction method was developed for the analysis of phytochemicals found in soy and processed soy products, which is reproducible in other laboratories. The extracts can be analyzed with standard liquid chromatography-mass spectrometry and high-performance liquid chromatography methods to identify and quantitate the group A and group B forms of the soy saponins, as well as the soy isoflavones. Complete saponin analysis of the extracts prepared from soy germ (hypocots), hulls, and cotyledons shows that a significant portion of the saponins is concentrated in the germ. The germ contains nearly all of the group A soyasaponins, while the group B soyasaponins are nearly equally distributed between the germ and the cotyledons. The hulls contain little of either isoflavones or saponins. Whole (full fat) soybeans grown on a tract in central Illinois in 2003 contain approximately 4-6% saponins on a weight basis, of which about one-fifth or less of the total saponin content are group A soyasaponins; the balance is group B soyasaponins.

No abstract

Modafinil (Provigil) is a new wake-promoting drug that is being used for the management of excessive sleepiness in patients with narcolepsy. It has pharmacological properties similar to that of amphetamine, but without some of the side effects associated with amphetamine-like stimulants. Since modafinil has the potential to be abused, accurate drug-screening methods are needed for its analysis. In this study, we developed a high-performance liquid-chromatographic procedure (HPLC) for the quantitative analysis of modafinil in plasma and urine. (Phenylthio)acetic acid was used as an internal standard for the analysis of both plasma and urine. Modafinil was extracted from urine and plasma with ethyl acetate and ethyl acetate-acetic acid (100:1, v/v), respectively, and analyzed on a C18 reverse phase column with methanol-water-acetic acid (500:500:1, v/v) as the mobile phase. Recoveries from urine and plasma were 80.0 and 98.9%, respectively and the limit of quantitation was 0.1 microg/mL at 233 nm. Forty-eight 2-h post-dose urine samples from sham controls and from individuals taking 200 or 400 mg of modafinil were analyzed without knowledge of drug administration. All 16-placebo urine samples and all 32 2-h post-dose urine samples were correctly classified. The analytical procedure is accurate and reproducible and can be used for therapeutic drug monitoring, pharmacokinetic studies, and drug abuse screening.

1,2-Diol functional groups are common structures in many biologically active natural products [1] and "privileged" chiral catalysts/ligands. [2] Furthermore, 1,2-diols can serve as valuable synthetic precursors for the construction of a wide variety of other useful structures. 1,2-Diols can appear in many different forms depending on their protection state (diprotected, monoprotected, or free diol), as well as their absolute and relative stereochemistry (syn or anti). Thus, an ideal synthetic method/strategy for 1,2-diols would be one that can a) furnish any of the aforementioned 1,2-diol forms and b) control their absolute and relative stereochemistry by using a pair of enantiomeric ligands/catalysts, but such methodology is not currently available.Despite tremendous methodological advancements, literature inspection surprisingly revealed that almost all prior asymmetric methods for the synthesis of 1,2-diols focused on controlling relative stereochemistry of 1,2-diols, thus giving either syn-or anti-1,2-diols, and employed chiral reagents and auxiliaries for stereochemical control. [3][4][5][6][7][8] In addition, they often suffered from a narrow substrate scope, low yields, and low stereoselectivities. To our knowledge, the only catalytic asymmetric method that met the above two criteria was recently reported by the McQuade group, who employed the copper-catalyzed asymmetric allylic boronation/cross-metathesis (AAB/CM) strategy. [9] Although highly selective formation of differentiated syn-and anti-1,2-diols could be achieved by using a pair of enantiomeric ligands, the strategy required two extra steps for the in situ oxidation of the boronate product of the AAB reaction and the subsequent alcohol protection, and the AAB reaction did not occur with a TBS protecting group, thus considerably limiting the generality and practicality of the strategy.In recent years, iridium(I)-catalyzed allylic substitution reactions have emerged as a powerful tool for the enantioselective introduction of carbon-carbon and carbon-heteroatom bonds. [10] A distinct feature of iridium(I)-catalyzed allylic substitution reactions is the formation of chiral branched allylation products from achiral linear allyl sub-strates, which complements the more traditional palladiumcatalyzed allylic substitution reactions which typically give rise to linear allylation products. [11] Iridium-catalyzed allylic etherification reactions have been shown to generate a wide range of protected and free chiral allylic alcohols in high yields at synthetically useful levels of stereoselectivity [Eq. (1); PG = protecting group]. [12] We recently demonstrated that iridium(I)-catalyzed decarboxylative allylic etherification exhibited much broader substrate scope and higher reaction yield than the corresponding intermolecular version, and that stereoselection in iridium(I)-catalyzed diastereoselective decarboxylative allylic etherification was controlled by the ligands/catalysts used [Eq.(2); PMP = p-methoxyphenyl]. [13] Based on these results, we envision...

Ir(I)-catalyzed enantioselective decarboxylative allylic etherification of aryl allyl carbonates provides aryl allyl ethers. Key to the generality and high stereoselection of the reaction is the use of the intramolecular decarboxylative allylation process and [Ir(dbcot)Cl](2) as an Ir(I) source. Ir(I)-catalyzed diastereoselective decarboxylative allylic etherification, combined with asymmetric aldehyde crotylation and cross metathesis, can furnish monoprotected 2-methyl-1,3-diols (starting from simple aldehydes) with high diastereoselectivities.