Three-component cascade reactions of (E)-3-arylidene-1-methyl-pyrrolidine-2,5-diones, L-valine and various isatin derivatives are described. A series 17 spiropyrrolidine with wide structural complexity diversity have been thus obtained in moderate to excellent yields under mild reaction conditions. The structure stereochemistry these N-heterocyclic cycloadducts has established by spectroscopic ...

Radical-radical cross coupling reactions of photoexcited 9-fluorenones have been accomplished for the first time, leading to the synthesis of 9-alkyl, pyrollidinyl and spiro-THF derivatives of 9-fluorenones. The method also reveals, for the first time, the behaviour of ketyl radicals in decarboxyaltive alkylation and ring expansion reactions.

A facile and efficient one-pot synthesis of pyrrolidines and dispiro pyrrolidines/pyrrolizidines has been accomplished by the 1,3-dipolar cycloaddtion reaction of azomethine ylides generated insitu from paraformaldehyde/ninhydrin and secondary amino acids with electron-deficient dipolarophiles in good yield. The reaction proceeded with high regio and stereoselectivity. The products have been ch...

Intramolecular [2+2] photocycloaddition reactions of diversely substituted N-Boc protected 4-(allylaminomethyl)-2(5H)-furanones resulted in rigid products (53-75%) with three spatially defined positions for further functionalisation.

accumulating evidence indicates that aldosterone plays a critical role in the mediation of oxidative stress and vascular damage. nadph oxidase has been recognized as a major source of oxidative stress in vasculature. however, the relation between nadph oxidase in aldosterone-mediated oxidative stress in endothelial cells remains to be ascertained. the present study aimed to investigate the rele...

A straightforward synthesis of novel, 2-heterocyclyl polyhydroxylated pyrrolidines is described. Stereocontrolled additions of nucleophiles to cyclic nitrones generated the corresponding 2,3-trans adducts, allowing the synthesis of the corresponding pyrrolidines via key intermediates bearing an alkyne and a nitrile oxide. Three hybrid systems, including a pyrrolidine with two isoxazoles and one...

Substituted pyrrolines are available by ring closure initiated by direct nucleophilic attack of stabilized enolates at the nitrogen of oximes activated with a leaving group, in a process which effectively out-competes the more usual Beckmann rearrangement. Subsequent reduction provides diastereoselective access to the corresponding pyrrolidines. This provides a rapid route to saturated heterocy...

Heterocyclic compounds containing β-lactum structure with different hetero atoms are found to show biological activities1. In the present work, it has been synthesized the semicarbozone and thiosemicarbozone derivatives of 3-methyl-2,6-diphenylpiperidin-4-one followed bycyclisation to get the spiro compounds. These spiro compounds. The spiro products have been characterized by C,H,M analysis, I...

Nitrogen-centered radical cyclizations onto silyl enol ethers were utilized for the syntheses of protected polyhydroxylated pyrrolidines 2-hydroxymethyl-3-hydroxypyrrolidine and 1,4-dideoxy-1,4-imino-L-ribitol.

We propose a spectrum-dependent mechanism for the oxidation of 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (Spiro-OMeTAD) with bis(trifluoromethane)sulfonimide lithium salt (LiTFSI), which is commonly used in perovskite solar cells as the hole transport layer. The perovskite layer plays different roles in the Spiro-OMeTAD oxidization for various spectral ranges. The eff...