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A practical, safe and general method is described that has used a combination of diisopropylethylamine and sodium tert-butoxide. This method has allowed for preparing 4-hydroxyquinolinone esters and amides in good yields.

A highly efficient synthesis of the potent and selective NK-1 receptor antagonist is described. Mechanistic studies confirmed that the etherification reaction proceeds through an unprecedented [S.sub.N]2 reaction pathway under typical [S.sub.N]1 reaction conditions.

A highly efficient strategy is developed for the rapid asymmetric synthesis of gem-dimethyl and spirocyclopropyl norbornyl carboxylic acids. The key transformation involved the unprecedented asymmetric Diels-Alder reaction of highly reaction beta,beta-cyclopropyl-alpha,beta-unsaturated N-acyloxazolidinoones with cyclopentadiene affording the adducts in high yield and de.

N-acyl-2-alkyl(aryl)-5-vinyl-2,3-dihydro-4-pyridones undergoes Diels-Alder cyclization with various dienophiles to afford novel octahydroquinolines. With dihydropyridone and cis-disubstituted dienophiles, the resulting cycloadducts are obtained as single diastereomers in good to excellent yield.

A number of approaches for the synthesis of the 1H-indol-2-yl-1H-quinolin-2-one ring system found in the potent and selective kinase insert domain receptor (KDR) inhibitor are described. The key structural feature of KDR inhibitors is the indol-2-ylquinolin-2-one ring system bearing a substituent in the 5-position of the indole ring.

Presenting the synthesis of 3 and related nitroketones and optimized conditions for their conversion to 2-substituted indoles of type 2. The examination of the reductive cyclization reaction and optimization of conditions is described.

Research has been conducted on the 1,2,3-trisubstituted cyclohexanes and cyclopentanes. The results of the asymmetric synthesis of these compounds developed for the preparation of the 2,3-disubstituted cyclohexenones and cyclopentenones are presented.

Research has been conducted on the alpha-sulfinylamides. The preparation of these compounds has been carried out via condensation of the primary amine with ketone and via the reaction of the resulting imine with ethylsulfenylacetyl chloride followed by the oxidation with sodium periodate.

Results point out that the Pummerer reaction of imidosulfoxides is a very efficient method for preparing azapolycyclic ring systems such as 4-azafluorenone, quinolizidine, and clavine. Data indicate that the cyclization-deprotonation-cycloaddition cascade reaction of imidosulfoxides can be employed for the synthesis of natural products.

The additive and vinylogous Pummerer reactions were observed to be useful for the synthesis of nitrogen heterocycles. The reaction sequence requires the formation of an electrophilic thionium ion intermediate which is intercepted by a pi-nucleophile tethered on the amide nitrogen. The overall transformations are highly effective techniques for transforming relatively simple starting compounds into complex nitrogen heterocycles.

A study has been conducted to investigate the reaction and reaction products of various alpha-diazo-beta-hydroxy esters with boron trifluoride etherate. The results revealed a high correlation between the ring size and the type of solvent in the different products. The reaction produced a cycloalkylidene diazonium salt and a destabilized linear vinyl cation, which formed upon the loss of nitrogen. The vinyl cation became stable after ring expansion via a 1,2-methylene shift. A further 1,2-methylene shift resulted to a stable allylic cation.

An efficient, practical, and high yielding synthesis of (R)-2-methylpyrrolidine is described. The sequence allows for the scalable preparation of the target compound in just four synthetic steps and proceeds in 83% overall yield and >99% optical purity from readily available starting materials.

One-pot iodination of hydroxypyridines and hydroxyquinolines are described. The iodination has proceeded under mild conditions and it has worked on both 2- and 4-hydroxypyridines and uhydroxyquinolines.

The development of a new efficient strategy for the preparation of 3-alkoxymethyl-pyrazolo[3,4-b]pyridines is reported. The compounds could be manipulated to access 3-alkoxymethyl-pyrazolo[3,4-b]pyridines with a variety of substitution patterns as well as 3-aminomethyl-pyrazolo[3,4-b]pyridines.

An efficient method for three-step preparation of (S)-N- ethoxycarbonyl-[alpha]-methylvaline from commercially available materials is described. The procedure involves resolution-crystallization of tartrate salt and requires no chromatographic separations.

The practical methodologies which have either been successfully demonstrated or are potentially useful for the large-scale synthesis of indoles are described, with emphasis placed on those reactions leading to the indole ring. Fischer indole synthesis, reductive cyclization, Leimgruber-Batch indole synthesis, Nenitzescu indole synthesis, Heck Cyclizations are some of the processes that lead to formation of indole ring.

An efficient strategy is developed for the rapid and efficient one-pot synthesis of 2-aryl-5-substituted-2,3-dihydrobenzofurans from readily available o-nitrotoluenes and aromatic aldehydes. This strategy allows access to a structurally diverse array of products for further manipulation.

Reporting a general synthesis of symmetrically and unsymmetrically 1,3-disubstituted imidazo[4,5-b]pyridin-2-ones 1b through palladium-catalyzed cross coupling. This method allows for the preparation of novel heterocycles that are pharmaceutically interesting in two or three synthetic steps which are not accessible through current synthetic methods.

The asymmetric total synthesis of natural (+)-cannabisativine was completed in 19 steps in a study, with 7 percent overall yields. Investigation of several approaches to the macrocyclic ring closure of the 13-membered ring ultimately led to the completion of an asymmetric synthesis of the target compound with a high degree of stereocontrol.

A study was conducted, by examining the addition of the simple Grignard reagents, to verify whether indolyl and pyrrolyl Grignard reagents would add to chiral 1-acylpyridinium salts. The study reveals that the addition of indolyl and pyrrolyl Grignard in the 1-acylpyridinium salts reactions yields more.

Formation of N-hydroxyindoles, through a lead-promoted intramolecular reductive cyclization of 0-nitrobenzyl ketones, and aldehydes under transfer hydrogenation conditions, is discussed