Current Organic Synthesis - Volume 11, Issue 6, 2014

The Barton-McCombie reaction (B-M reaction) is deoxygenation of aliphatic alcohols via thioacylation followed by a radical cleavage. Variations of the reactions may utilize different thioacyl fragments and hydrogen sources. In this review article, however, we have focused on the applications of this reaction as a mild and functional group tolerant method in deoxygenation step in total syntheses of some well recognized natural products.

Imidazoles are a fascinating group of heterocyclic molecules with varying biological properties. Additionally, they form the nucleus of several commercial drugs. In this review, we describe the history of imidazoles from their discovery to their structural determination. We show that different synthetic methodologies are found in the literature. However, this review focuses on the evolution of the Radziszewski reaction Read More

Heterocycles constitute the largest diversity of organic molecules of chemical, biomedical, and industrial significance. They widely exist in numerous natural products, such as vitamins, hormones, antibiotics, alkaloids, herbicides, and dyes. They are also among the most frequently encountered scaffolds in numerous drugs and pharmaceutically relevant substances. This review highlights some remarkable achievem Read More

Many efforts have been made for developing novel and efficient methods to synthesize the glycosylated natural products. This review summed up recent advances on the synthesis of glycosylated natural products.

This present mini-review summarizes the recently published development and trends concerning catalysts based on immobilized complexes of transition metals which are designated for asymmetric Henry reaction. The paper presents examples of originally homogeneous catalysts which were anchored to organic carriers (such as dendrimers, polymers) or inorganic materials. The catalysts based on organic carriers are cl Read More

The pyrrolidine ring can be found in numerous natural products and in many pharmaceuticals. Hygrine, as an example of a pyrrolidine alkaloid, is the biosynthetic precursor of pharmacologically important tropane alkaloids. This review summarizes the synthetic routes toward racemic and enantiopure hygrine.

3,6-diphenyl-1,2,4,5-tetraoxane(DFT) has been prepared in order to study the effect of temperature on the reaction kinetics in methylcellosolve solution. The thermolysis reaction fulfills a kinetic law of the first order up to conversions approximately 60 % of the DFT. The values of ΔH#=20.2±1.0 kcal mol-1 and ΔS#= -25.3±1.4 cal mol-1 K-1 of the rupture of one O-O bond in the diperoxide molecule were obtained Read More

Ketones were prepared by a modified Nef reaction using heterocyclic aryl nitroalkenes to react in a Fe-FeCl3-CH3COOH mixture with higher yield over 50% in sharp contrast with in Fe-HCl mixture with lower yield less than 30%, thus it’s cost-saving and relative environment friendly.

By an efficient biomimetic synthetic method, several novel 2-substituted benzimidazoles, benzoxazoles, and benzothiadazole were readily prepared in good yields under mild conditions with 2-substituted imidazolinium iodides as the tetrahydrofolate model compounds at the oxidation level of formate. The reaction is probably involved in a nucleophilic addition to the C=N bond at the imidazolinium ring, followed a 1,3-H migrati Read More

Novel bisquinoline derivatives of tetraazamacrocyclic compounds, namely 4,10-bis(7-chloroquinoline)-1,4,7,10-tetraazacyclododecane (1, Scheme 1); 4,10-bis(7-chloroquinoline)-1,7-dimethyl-1,4,7,10-tetraazacyclododecane (6, Scheme 2); 4,11-bis(7-chloroquinoline)- 1,4,8,11-tetraazabicyclo[6.6.2]hexadecane (6a, Scheme 3) and 4,10-bis(7-chloroquinoline)-1,4,7,10-tetraazabicyclo[5.5.2] tetradecane (6b, Sche Read More

Studies were carried out to explore reactions of the enaminal, N,N-dimethylaminoacrolein (1c), with active methylene compounds. The results show that 1c reacts with 3-oxoalkanenitriles 2a and 2b to yield either the respective 2-(N,N-dialkylamino)pyridines 6a and 6b or pyridine-3-carbonitriles 7a and 7b depending on the reaction conditions. In addition, 1c reacts with malononitrile in ethanolic piperidine to produce N,N-dimethyl Read More